The effect of body mass index on major outcomes after vascular surgery

Utility of Psoas Muscle Index as Predictor of Worse Outcomes Following Major Amputation from Peripheral Vascular Disease

BACKGROUND

Frailty has been reported as a predictor of adverse outcomes after various surgical procedures. There are several models for defining frailty, including 5-factor modified frailty index, clinical frailty scale, and psoas muscle index. Low psoas muscle index has been associated with higher postoperative mortality and complications after various surgical procedures. Our objective was to assess psoas muscle index as a predictor of outcomes after major amputation in patients with peripheral vascular disease.

METHODS

We performed retrospective chart review of patients with peripheral vascular disease who underwent major amputation at a safety-net hospital from 2016 to 2022. Psoas index was evaluated based on computed tomography scans within 6 months of amputation. Outcomes included postoperative 30-day mortality, wound complications, respiratory complications, cardiac complications, and 1-year mortality. Psoas muscle index was calculated using psoas muscle area measured from computed tomography scans at the level of the L4 vertebral body divided by the body surface area. Univariate and multivariate analysis was used to compare postoperative outcomes by gender and by psoas muscle index.

RESULTS

A total of 106 patients were analyzed (68 males, 38 females). Females had higher rates of above-knee amputation (AKA) compared to males (55.2% vs. 27.9%, P = 0.04). Males had a significantly higher baseline mean psoas muscle index compared to females (1,088 mm2/m2 vs. 787 mm2/m2, P < 0.01). AKA within 30 days (20% vs. 10.8%, P = 0.05) and respiratory complications (9.5% vs. 1.2%, P = 0.04) were more likely in patients with low psoas muscle index compared to those with high psoas muscle index when low psoas muscle index was defined as the lowest 20th percentile of patients. Females with a low psoas muscle index were more likely to have wound complications (60% vs. 21%, P = 0.03). Females were more likely to require AKA within 30 days after below knee amputation (19.4% vs. 9%, P = 0.02) and have a higher rate of mortality at 1 year (45.8% vs. 23.1%, P = 0.04) compared to males regardless of psoas index.

CONCLUSIONS

Our results demonstrate that low psoas muscle index is associated with worse outcomes after major amputation for peripheral vascular disease, particularly in female patients. These data may be helpful for preoperative risk assessment and decision-making regarding amputation level.

Effect of obesity on patient outcomes after aortobifemoral bypass in the treatment of aortoiliac occlusive disease

ObjectiveThe purpose of this study was to evaluate the impacts of obesity on patients undergoing aortobifemoral bypass for aortoiliac occlusive disease (AIOD). AIOD is an atherosclerotic disease of the suprainguinal arteries, and treatment approaches are often guided by the TASC II classification. The obesity paradox, a phenomenon where higher-than-normal BMI individuals exhibit better outcomes in various medical conditions, has yet to be fully understood in the context of AIOD.MethodsThe American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database was queried for AIOD cases between January 1, 2011 and December 31, 2016. All patients included in the AIOD targeted files were eligible for inclusion unless their BMI was missing. Patient demographics and surgical characteristics were analyzed across BMI, categorized as underweight (<18.5), normal (18.5-24.9), overweight (25.0-29.9), obese (30-34.9), and very obese (≥35). Multivariable logistic and linear regression models, adjusting for demographics, comorbidities, and AIOD symptoms, were used to estimate the association between BMI and patient outcomes.ResultsOverall, 4885 patients met inclusion criteria, of which 274 (6%) patients were underweight, 1720 (35%) were normal weight, 1649 (32%) were overweight, 843 (16%) were obese, and 399 (8%) were very obese. Among all groups, neither age nor symptoms were significantly different. The functional status of the patients across all groups was also similar. Compared to normal-weight patients, obese and very obese patients were significantly more likely to be diabetic (34% and 50% vs 16%) and have hypertension (82% and 84% vs 5%), p < .0001. Both obese (OR 2.11, 95% CI 1.47, 3.04) and very obese patients (OR 2.94, 95% CI 1.95, 4.45) had significantly higher incidences of infection. Very obese patients also had a higher incidence of pneumonia (OR 2.03, 95% CI 1.11, 3.74) and prolonged ventilator requirement (OR 3.09, 95% CI 1.86, 5.14) compared to normal-weight patients. No differences were seen in mortality (p = .92) or length of stay (p = .20).ConclusionAn elevated body mass index (BMI) is associated with a higher vulnerability to infection, pneumonia, and an extended need for ventilation after open aortobifemoral bypass surgery. However, there was no association between BMI and 30-day mortality or duration of hospitalization in patients who had AOBF bypass.

The association between BMI and postoperative pulmonary complications in adults undergoing non-cardiac, non-obstetric surgery: a retrospective cohort study

INTRODUCTION

Conflicting results have been reported regarding the influence of BMI on postoperative adverse events. The aim of this study was to investigate the association between BMI and postoperative pulmonary complications in adults undergoing non-cardiac, non-obstetric surgical procedures.

METHODS

This large-scale retrospective study included 125,082 adults who underwent surgery at a university-affiliated tertiary care hospital between 2019 and 2023. The primary endpoint was the incidence of postoperative pulmonary complications. Multivariable logistic regression analyses, subgroup analyses, sensitivity analyses and restricted cubic splines were used to assess the association between BMI and postoperative pulmonary complications.

RESULTS

A total of 6671 patients (5.3%) developed one or more postoperative pulmonary complications. After adjusting for confounders, compared with those patients with a normal weight (BMI 18.5-24.9 kg.m-2), patients who were underweight (BMI < 18.5 kg.m-2) had an increased risk of postoperative pulmonary complications (OR 1.24, 95%CI 1.12-1.39, p < 0.001). Patients who were overweight (BMI 25.0-29.9 kg.m-2) or living with class 1 obesity (BMI 30.0-34.9 kg.m-2) had a lower risk of postoperative pulmonary complications (OR 0.88, 95%CI 0.83-0.94, p < 0.001 and OR 0.82, 95%CI 0.70-0.96; p = 0.01, respectively). Patients living with obesity class 2/3 (BMI ≥ 35 kg.m-2) had a similar risk of postoperative pulmonary complications as patients with a normal weight (OR 1.23, 95%CI 0.91-1.66, p = 0.17). There was a J-shaped association between BMI and incidence of postoperative pulmonary complications with the lowest risk at a BMI of 27.4 kg.m-2.

DISCUSSION

Patients who were overweight or living with class 1 obesity undergoing non-cardiac, non-obstetric surgery had paradoxically lower risks of postoperative pulmonary complications compared with those of a normal weight. These findings may contradict traditional assumptions about surgical risk and obesity, highlighting the need to re-evaluate the relationship between BMI and postoperative pulmonary complications.

Influence of body mass index on functional and surgical outcomes in transaxillary thoracic outlet decompression for neurogenic thoracic outlet syndrome

OBJECTIVE

Despite an increase in prevalence of obesity over the last decades, few studies examine the influence of body mass index (BMI) on the outcome of thoracic outlet decompression (TOD) for neurogenic thoracic outlet syndrome (NTOS). However, it is important to understand the safety and efficacy of this procedure in patients with elevated BMI. This study aimed to determine the influence of BMI on surgical and functional outcomes following transaxillary TOD in patients with NTOS.

METHODS

We performed a retrospective review of a prospectively collected database with patients who underwent transaxillary TOD for NTOS from July 2016 to January 2023. Patients were categorized into three groups according to their BMI, normal weight (<25.0 kg/m2), overweight (25.0-30.0 kg/m2), and obesity (>30.0 kg/m2). Primary outcomes were peri- and postoperative complications, such as hematoma, scapula alata, Horner syndrome, and wound infections. Secondary outcomes were length of stay, drain placement duration, pleural catheter placement duration, and functional outcome. Functional outcome was evaluated by using the Derkash classification; Disability of the Arm, Shoulder, and Hand questionnaire; and Cervical Brachial Symptom questionnaire scores up to 24 months of follow-up.

RESULTS

The surgical results of 346 patients undergoing NTOS were analyzed. Of these patients, 191 (55.2%) were classified as normal weight, 98 (28.3%) as overweight, and 57 (16.5%) as obese. No significant difference in complication rates between BMI groups was found (P = .672). All groups had significant postoperative improvements in Disability of the Arm, Shoulder, and Hand questionnaire and Cervical Brachial Symptom Questionnaire scores (P < .001). There were no significant differences in functional outcomes between the three BMI groups.

CONCLUSIONS

The transaxillary approach for surgical treatment of NTOS can be used safely and effectively in patients of all BMI groups.

Factors associated with nonhome discharge after endovascular aneurysm repair

OBJECTIVE

This study aims to identify preoperative factors associated with nonhome discharge (NHD) after endovascular aneurysm repair (EVAR). NHD has implications for patient care, readmission, and long-term mortality; nevertheless, the existing literature lacks information regarding factors associated with NHD for patients undergoing EVAR. In contrast, our study assesses preoperative factors associated with NHD for this population by using national data from the Vascular Quality Initiative.

METHODS

We identified adult patients who underwent elective EVAR in the Vascular Quality Initiative (2003-2022) and excluded those who were not living at home preoperatively. Multivariable logistic regression was used to identify preoperative factors associated with NHD. Kaplan-Meier methods and Cox-regression analyses were used to assess the impact of NHD on 5-year survival as a secondary outcome.

RESULTS

We included 61,792 patients, of which 3155 (5.1%) had NHD. NHD patients were more likely to be older (79 years [interquartile range, 73-18 years] vs 73 years [interquartile range, 67-79 years]), female (33.7% vs 18.2%; P < .001), non-White (16.0% vs 11.7%; P < .001), and have more comorbidities. NHD patients had higher rates of postoperative complications (acute kidney injury, 11.9% vs 2.0% [P < .001]; myocardial infarction, 3.8% vs 0.5% [P < .001]; and in-hospital reintervention, 4.7% vs 0.5% [P = .033]). Multivariable analysis revealed many preoperative characteristics were associated with higher odds of NHD: most notably, age (per additional decade: odds ratio [OR], 2.15; 95% confidence interval [CI], 2.03-2.28; P < .001), female sex (OR, 1.79; 95% CI, 1.63-1.95; P < .001) and aneurysm diameter >65 mm (OR, 2.18; 95% CI, 1.98-2.39; P < .001), along with potentially modifiable factors, including anemia, chronic obstructive pulmonary disease, chronic heart failure, weight, and diabetes. In contrast, aspirin, statin, and angiotensin-converting enzyme inhibitor/angiotensin II receptor blocekr use were associated with lower odds of NHD. NHD was associated with higher hazards of 5-year mortality, even after adjusting for confounders (40% vs 14%; adjusted hazard ratio, 2.13; 95% CI, 1.86-2.44; P < .001).

CONCLUSIONS

Several factors were associated with higher odds of NHD after elective EVAR, including nonmodifiable factors such as female sex and larger aortic diameter, and potentially modifiable factors such as anemia, chronic obstructive pulmonary disease, chronic heart failure, body mass index, and diabetes. Special attention should be given to populations with nonmodifiable factors, and efforts at optimizing medical conditions with higher NHD likelihood seems appropriate to improve patient outcomes and quality of life after EVAR.

Impact of class of obesity on clinical outcomes following fenestrated-branched endovascular aneurysm repair

BACKGROUND

Obesity represents a prevalent and escalating health concern among vascular surgery patients. Evidence pertaining to the influence of body mass index (BMI) on clinical outcomes after fenestrated-branched endovascular aneurysm repair (B/FEVAR) remains unclear. This study aims to assess the effect of obesity on short- and midterm clinical outcomes among individuals undergoing B/FEVAR.

METHODS

This was a single-center retrospective analysis of all patients who underwent B/FEVAR from 2007 to 2020, with a median follow-up of 3.3 years (interquartile range, 1.6-5.3 years). Obesity was defined as a BMI of ≥30 kg/m2. Patients were divided into nonobese (NO) and obese cohorts according to their BMI. Outcomes were compared between the two groups subsequently.

RESULTS

A total of 264 patients, 96 obese and 168 NO, were included. Patients with obesity were younger (72.8 ± 6.9 years vs 76.0 ± 7.3 years; P < .001), but had a higher prevalence of diabetes mellitus (27.1% vs 12.0%; P = .01) and dyslipidemia (80.2% vs 68.5%; P = .03). Both cohorts had similar rates of percutaneous access (37.5% for obese vs 35.1%; P = .7), and no significant differences in the rate of conversion to open access (8.3% for obese vs 4.2% for NO; P = .16). Technical success was similar between the cohorts (89% for obese vs 86%; P = .59). Major adverse events (MAEs) were higher in the NO group (13.1% vs 4.2%; P = .02). Patients in the obese cohort suffered more access site related infections (7.3% vs 1.2%; P = .01). All-cause mortality over 5 years was significantly higher in the NO group (35.1% vs 21.9%; P = .02). No statistical differences were found in spinal cord injury or dialysis requirement rates. Furthermore, on follow-up at 5 years, endoleak, branch instability, and reintervention rates were not statistically different between the two cohorts.

CONCLUSIONS

Patients with obesity are on average younger; however, they were more likely to suffer access site infections compared with NO patients. They had increased survival rates on follow-up, although rates of reinterventions and endoleaks were similar between the two cohorts. Our study demonstrates that, despite higher comorbidities, patients with obesity had similar intraoperative success with decreased postoperative mortality; however, access site infections remains a significant clinical concern.

Impact of body mass index on in-hospital outcomes in patients receiving leadless pacemakers: A five-category analysis

Background

The adoption of leadless pacemakers (LPMs) is increasing, yet the impact of body mass index (BMI) on procedural outcomes remains underexplored.

Objective

The purpose of this study was to explore the impact of BMI on in-hospital outcomes for patients receiving LPM implantation.

Methods

Data from the National Inpatient Sample from 2018-2021 were analyzed for patients older than 18 years who underwent LPM implantation, with specific inclusion and exclusion criteria applied. Patients were identified using International Classification of Diseases 10th Revision codes and categorized into BMI groups: underweight, normal, overweight, obese, and morbidly obese. The primary outcome assessed was in-hospital mortality. Secondary outcomes included blood transfusion, pericardial complications, infection/inflammation, removal/revision, and other complications.

Results

The study included 3832 patients who underwent LPM implantation between 2018 and 2021, weighted to represent 19,610 patients, with 3540 having an appropriate BMI designation. Mortality was lower in the obese group (2.3%) compared to the nonobese group (2.7%) (adjusted odds ratio [aOR] 0.462, 95% confidence interval [CI] 0.259-0.623, P = .009). Compared to the normal weight group, those categorized as overweight, obese, and morbidly obese demonstrated a lower risk of in-hospital mortality (aOR 0.432, 95% CI 0.299-0.734, P = .009; aOR 0.465, 95% CI 0.238-0.721, P <.001; aOR 0.299, 95% CI 0.153-0.586, P <.001, respectively).

Conclusion

These findings support the existence of the obesity paradox in patients with LPM implantation, where higher BMI categories are associated with improved mortality outcomes, meeting our prespecified primary endpoint. Further studies are needed to clarify the mechanisms behind these observations.

The Effects of Body Mass Index on Postoperative Complications in Patients Undergoing Autologous Free Flap Breast Reconstruction

BACKGROUND

 The prevalence of obesity in the United States exceeds 40%, yet perioperative effects of higher body mass index (BMI) in autologous breast reconstruction remain poorly studied. The purpose of this study was to investigate BMI's impact on postop complications in abdominal and gluteal-based autologous breast reconstruction.

METHODS

 We conducted a retrospective study using TriNetX, a health care database containing de-identified data from more than 250 million patients. Patients undergoing autologous breast reconstruction were identified by Current Procedural Terminology codes. Four cohorts were established by BMI class: <24.99, 25 to 29.99, 30 to 34.99, and 35 to 39.99 kg/m2. Outcomes of interest were defined by International Classification of Diseases, Tenth Revision (ICD-10) codes. A two-sample t-test was performed to compare incidence of postoperative complications between cohorts within 3 months of surgery. Patients with a BMI < 24.99 kg/m2 served as the control. Cohorts were balanced on age, race, and ethnicity.

RESULTS

 We identified 8,791 patients who underwent autologous breast reconstruction. Of those, 1,143 had a BMI < 24.99 kg/m2, 1,867 had a BMI of 25 to 29.99 kg/m2, 1,396 had a BMI of 30 to 34.99 kg/m2, and 559 had a BMI of 35 to 39.99 kg/m2. Patients with a BMI of 25 to 29.99 kg/m2 had a significantly increased risk of cellulitis. Patients with a BMI of 30 to 34.99 and 35 to 39.99 kg/m2 had a significantly increased risk of cellulitis, surgical site infection, need for debridement, wound dehiscence, and flap failure.

CONCLUSION

 Our study illustrates that there is an increased risk of postoperative complications associated with higher BMI classes. Understanding these data are imperative for providers to adequately stratify patients and guide the procedural decision-making.

Clinical Outcomes of 5000 IU Heparin Versus Activated Clotting Time-Guided Heparinization During Noncardiac Arterial Procedures: A Propensity Score Matched Analysis

PURPOSE

Previous studies have shown that activated clotting time (ACT)-guided heparinization leads to better anticoagulation levels during noncardiac arterial procedures (NCAP) than a standardized bolus of 5000 IU. Better anticoagulation should potentially result in lower incidence of thrombo-embolic complications (TEC). Comparative investigations on clinical outcomes of these heparinization strategies are scarce. This study investigated clinical outcomes of ACT-guided heparinization with a starting dose of 100 IU/kg in comparison with a single standardized bolus of 5000 IU heparin during NCAP.

MATERIALS AND METHODS

Analysis from a prospectively collected database of patients undergoing NCAP in 2 vascular centers was performed. Patients receiving ACT-guided heparinization were matched 1:1 with patients receiving 5000 IU heparin using propensity score matching (PSM). Primary outcomes were TEC, bleeding complications, and mortality within 30 days of procedure or during the same admission.

RESULTS

A total of 759 patients (5000 IU heparin: 213 patients, ACT-guided heparinization: 546 patients) were included. Propensity score matching resulted in 209 patients in each treatment group. After PSM, the groups were comparable, with the exception of a higher prevalence of peripheral arterial disease in the ACT-guided heparinization group (103 patients, 49% vs 82 patients, 39%, p=0.039). The target ACT (>200 seconds) was reached in 198 patients (95%) of the ACT-guided group versus 71 patients (34%) of the 5000 IU group (p<0.001), indicating successful execution of the ACT-guided protocol. Incidence of TEC (13 patients, 6.2% vs 10 patients, 4.8%, p=0.52), mortality (3 patients, 1.4% vs 0 patients, p=0.25), and bleeding complications (32 patients, 15% vs 25 patients, 12%, p=0.32) did not differ between patients receiving ACT-guided heparinization and 5000 IU heparin. Protamine was administered in 118 patients (57%) in the ACT group versus 11 patients (5.3%) in the 5000 IU group (p<0.001), but did not influence incidence of TEC (17 patients, 5.9% vs 6 patients, 4.7%, p=0.61) or bleeding complications (34 patients, 12% vs 22 patients, 17%, p=0.14).

CONCLUSION

No difference in TEC, bleeding complications, or mortality was found between ACT-guided heparinization and a single bolus of 5000 IU heparin during NCAP.

CLINICAL IMPACT

Previous studies have shown that activated clotting time (ACT)-guided heparinization leads to better anticoagulation levels during non-cardiac arterial procedures (NCAP) then a standardized bolus of 5000 IU. Comparative investigations on clinical outcomes are scarce. This study focussed on clinical outcomes of both protocols in NCAP in a propensity score matched cohort. Thrombo-embolic complications (TEC), bleeding complications and mortality within 30 days after NCAP or during the same admission were comparable between groups. Future studies should focus on optimizing ACT-guided protocols, specifically in patients with a high risk of TEC and bleeding complications.

Obesity and the obesity paradox in abdominal aortic aneurysm

Obesity, characterized by its complexity and heterogeneity, has emerged as a significant public health concern. Its association with increased incidence and mortality of cardiovascular diseases stems not only from its complications and comorbidities but also from the endocrine effects of adipose tissue. Abdominal aortic aneurysm (AAA), a chronic inflammatory condition, has been closely linked to obesity. Intriguingly, mild obesity appears to confer a protective effect against AAA mortality, whereas severe obesity and being underweight do not, giving rise to the concept of the "obesity paradox". This review aims to provide an overview of obesity and its paradoxical relationship with AAA, elucidate its underlying mechanisms, and discuss the importance of preoperative weight loss in severely obese patients with AAA.

Cardiopulmonary exercise testing, computed tomography-derived body composition, systemic inflammation and survival after elective abdominal aortic aneurysm repair: A retrospective cohort study

BACKGROUND

Cardio-pulmonary exercise testing (CPEX) is selectively used before intervention for abdominal aortic aneurysm (AAA). Sarcopenia, a chronic condition defined by reduced skeletal muscle function and volume, can be assessed radiologically by computed tomography (CT)-derived body composition analysis (CT-BC), and is associated with systemic inflammation.

OBJECTIVE

The aim was to describe the association between CT-BC, CPEX, inflammation and survival in patients undergoing elective intervention for AAA.

SETTING

Patients were recruited retrospectively from a single, secondary-care centre-operative database. Cases undergoing elective endovascular aneurysm repair (EVAR) and open surgical repair (OSR) between 31 March 2015 and 25 June 2020 were included.

PATIENTS

There were 176 patients (130 EVAR, 46 OSR) available for analysis in the final study; median (interquartile range [IQR]) follow-up was 60.5 [27] months, and all completed a minimum of 2 years follow-up.

MAIN OUTCOME MEASURES

Preoperative CPEX tests were recorded. CT sarcopenia score [CT-SS, range 0 to 2, calculated based on normal/low SMI (0/1) and normal/low SMD (0/1)] assessed radiological sarcopenia. Preoperative modified Glasgow Prognostic score (mGPS) was used to assess systemic inflammation.

RESULTS

Mean [95% confidence interval (CI) survival in the CT-SS 0 vs. CT-SS 1 vs. CT-SS 2 subgroups was 80.1 (73.6 to 86.6) months vs. 70.3 (63.5 to 77.1) months vs. 63.8 (53.4 to 74.2) months] ( P  = 0.01). CT-SS was not associated with CPEX results ( P  > 0.05). Elevated CT-SS [hazard ratio (HR) 1.83, 95% CI, 1.16 to 2.89, P  < 0.01] was independently associated with increased hazard of long-term mortality; however, CPEX results were not ( P  > 0.05).

CONCLUSION

CPEX test results were not consistently associated with body composition and did not have significant prognostic value in patients undergoing elective treatment for AAA.

The effect of obesity on the outcome of thoracic endovascular aortic repair: a systematic review and meta-analysis

Background

Obesity is a well-known predictor for poor postoperative outcomes of vascular surgery. However, the association between obesity and outcomes of thoracic endovascular aortic repair (TEVAR) is still unclear. This systematic review and meta-analysis was performed to assess the roles of obesity in the outcomes of TEVAR.

Methods

We systematically searched the Web of Science and PubMed databases to obtain articles regarding obesity and TEVAR that were published before July 2023. The odds ratio (OR) or hazard ratio (HR) was used to assess the effect of obesity on TEVAR outcomes. Body mass index (BMI) was also compared between patients experiencing adverse events after TEVAR and those not experiencing adverse events. The Newcastle-Ottawa Scale was used to evaluate the quality of the enrolled studies.

Results

A total of 7,849 patients from 10 studies were included. All enrolled studies were high-quality. Overall, the risk of overall mortality (OR = 1.49, 95% CI [1.02-2.17], p = 0.04) was increased in obese patients receiving TEVAR. However, the associations between obesity and overall complications (OR = 2.41, 95% CI [0.84-6.93], p = 0.10) and specific complications were all insignificant, including stroke (OR = 1.39, 95% CI [0.56-3.45], p = 0.48), spinal ischemia (OR = 0.97, 95% CI [0.64-1.47], p = 0.89), neurological complications (OR = 0.13, 95% CI [0.01-2.37], p = 0.17), endoleaks (OR = 1.02, 95% CI [0.46-2.29], p = 0.96), wound complications (OR = 0.91, 95% CI [0.28-2.96], p = 0.88), and renal failure (OR = 2.98, 95% CI [0.92-9.69], p = 0.07). In addition, the patients who suffered from postoperative overall complications (p < 0.001) and acute kidney injury (p = 0.006) were found to have a higher BMI. In conclusion, obesity is closely associated with higher risk of mortality after TEVAR. However, TEVAR may still be suitable for obese patients. Physicians should pay more attention to the perioperative management of obese patients.

Impact of Serum Albumin Levels and Body Mass Index on Outcomes of Open Abdominal Aortic Aneurysm Repair in Korean Population

BACKGROUND

Although obese patients seem to be susceptible to chronic diseases, obesity paradox has been observed in the field of vascular surgery, in which many previous studies have reported that overweight patients have good postoperative outcomes and underweight patients have poor postoperative outcomes. The purpose of our study is to evaluate the impact of body mass index (BMI) and serum albumin levels, which are evaluated as indicators of nutritional status, on outcomes of open abdominal aortic aneurysm (AAA) repair.

METHODS

We reviewed the vascular surgery database of a single tertiary referral center for all patients who underwent open AAA repair due to degenerative etiology from 1996 to 2021. To analyze the effect of BMI, patients were classified into 4 groups according to the Asian-Pacific classification of BMI: underweight (UW) (<18.5 kg/m2), normal weight (NW) (18.5-22.9 kg/m2), overweight (OW) (23-24.9 kg/m2), and obese (OB) (≥25 kg/m2). The χ2, Fisher's exact, and Kruskal-Wallis tests were used to compare demographics, comorbidities, radiologic findings, surgical details, and 1-year mortality rates between the 4 groups. We also compared the preoperative serum albumin levels of each group to assess nutritional status indirectly. Cox's proportional hazards model was performed to determine factors associated with mortality. A Kaplan-Meier survival analysis was performed, and the differences were analyzed by a log-rank test. We did not perform an analysis for 30-day mortality because cases of 30-day mortality in UW patients were rare due to the unbalanced distribution of the number of patients in the 4 groups.

RESULTS

Among a total of 678 patients, 22 were classified as UW (3.2%), 200 as NW (29.5%), 183 as OW (27.1%), and 273 as OB (40.1%). The median age was 70 (64-75) years and 577 of 678 (85.1%) patients were male gender. Higher serum albumin level was associated with decreased 1-year mortality (hazard ratio [HR], 0.3; 95% confidence interval [CI], 0.15-0.63; P = 0.001). UW patients had a higher 1-year mortality rate than NW patients (HR, 3.67; 95% CI, 1.02-13.18; P = 0.046). OB patients had a lower overall mortality rate than NW patients (HR, 0.73; 95% CI, 0.53-1; P = 0.05).

CONCLUSIONS

Low BMI (<18.5 kg/m2) and low serum albumin level were associated with poor 1-year survival after elective open AAA repair. These patients also need more careful preoperative intervention, like weight gain or nutritional support, for better outcomes. The obesity paradox existed in our study; high BMI (≥25 kg/m2) was associated with better overall survival after elective open AAA repair.

Postoperative Staphylococcus aureus Infections in Patients With and Without Preoperative Colonization

Importance

Staphylococcus aureus surgical site infections (SSIs) and bloodstream infections (BSIs) are important complications of surgical procedures for which prevention remains suboptimal. Contemporary data on the incidence of and etiologic factors for these infections are needed to support the development of improved preventive strategies.

Objectives

To assess the occurrence of postoperative S aureus SSIs and BSIs and quantify its association with patient-related and contextual factors.

Design, Setting, and Participants

This multicenter cohort study assessed surgical patients at 33 hospitals in 10 European countries who were recruited between December 16, 2016, and September 30, 2019 (follow-up through December 30, 2019). Enrolled patients were actively followed up for up to 90 days after surgery to assess the occurrence of S aureus SSIs and BSIs. Data analysis was performed between November 20, 2020, and April 21, 2022. All patients were 18 years or older and had undergone 11 different types of surgical procedures. They were screened for S aureus colonization in the nose, throat, and perineum within 30 days before surgery (source population). Both S aureus carriers and noncarriers were subsequently enrolled in a 2:1 ratio.

Exposure

Preoperative S aureus colonization.

Main Outcomes and Measures

The main outcome was cumulative incidence of S aureus SSIs and BSIs estimated for the source population, using weighted incidence calculation. The independent association of candidate variables was estimated using multivariable Cox proportional hazards regression models.

Results

In total, 5004 patients (median [IQR] age, 66 [56-72] years; 2510 [50.2%] female) were enrolled in the study cohort; 3369 (67.3%) were S aureus carriers. One hundred patients developed S aureus SSIs or BSIs within 90 days after surgery. The weighted cumulative incidence of S aureus SSIs or BSIs was 2.55% (95% CI, 2.05%-3.12%) for carriers and 0.52% (95% CI, 0.22%-0.91%) for noncarriers. Preoperative S aureus colonization (adjusted hazard ratio [AHR], 4.38; 95% CI, 2.19-8.76), having nonremovable implants (AHR, 2.00; 95% CI, 1.15-3.49), undergoing mastectomy (AHR, 5.13; 95% CI, 1.87-14.08) or neurosurgery (AHR, 2.47; 95% CI, 1.09-5.61) (compared with orthopedic surgery), and body mass index (AHR, 1.05; 95% CI, 1.01-1.08 per unit increase) were independently associated with S aureus SSIs and BSIs.

Conclusions and Relevance

In this cohort study of surgical patients, S aureus carriage was associated with an increased risk of developing S aureus SSIs and BSIs. Both modifiable and nonmodifiable etiologic factors were associated with this risk and should be addressed in those at increased S aureus SSI and BSI risk.

Modified frailty index independently predicts morbidity in patients undergoing 3-column osteotomy

PURPOSE

Adult Spinal Deformity (ASD) includes a spectrum of spinal conditions that can be associated with significant pain and loss of function. While 3-column osteotomies have been the procedures of choice for ASD patients, there is also a substantial risk for complications. The prognostic value of the modified 5-item frailty index (mFI-5) for these procedures has not yet been studied. The goal of this study is to evaluate the association of mFI-5 with 30-day morbidity, readmission, and reoperation following a 3-column osteotomy.

METHODS

The National Surgical Quality Improvement Program (NSQIP) database was queried to identify patients undergoing 3-Column Osteotomy procedures from 2011-2019. Multivariate modeling was utilized to assess mFI-5 and other demographic, comorbidity, laboratory, and perioperative variables as independent predictors of morbidity, readmission, and reoperation.

RESULTS

N = 971. Multivariate analysis revealed that mFI-5 = 1 (OR = 1.62, p = 0.015) and mFI-5 ≥ 2 (OR = 2.17, p = 0.004) were significant independent predictors of morbidity. mFI-5 ≥ 2 was a significant independent predictor of readmission (OR = 2.16, p = 0.022) while mFI-5 = 1 was not a significant predictor of readmission (p = 0.053). Frailty did not predict reoperation.

CONCLUSION

Frailty as defined by mFI-5 strongly and independently predicted increased odds of postoperative morbidity for patients undergoing 3-column osteotomy as surgical intervention for ASD. Only mFI-5 ≥ 2 was a significant independent predictor of readmission, while frailty did not predict reoperation. Other variables independently predicted increased and decreased odds of postoperative morbidity, readmission, and reoperation.

LEVEL OF EVIDENCE

III.

Obesity is Not Associated with Adverse Perioperative or Poorer Clinical Outcomes following Thoracic and Fenestrated-Branched Endovascular Aortic Repair

BACKGROUND

Obesity is a risk factor for higher morbidity and mortality following open aortic repair but currently there is limited literature on its impact on clinical and procedural outcomes following thoracic endovascular aortic repair (TEVAR) and branched-fenestrated endovascular aortic repair (B-FEVAR).

METHODS

We conducted a retrospective case-control analysis of a prospectively collected nonrandomized database to evaluate the effects of obesity on procedural and clinical outcomes after B-FEVAR/TEVAR in treatment of pararenal/thoracoabdominal aortic aneurysm and dissection at the University hospital of Nantes (France) between January 2016 and December 2021. Patients were divided in 2 groups according to their body mass index (BMI) and the rate of technical success, complications (renal, pulmonary, cardiac, and neurological events), 30-day and long-term survival, freedom from target vessel instability and reintervention were compared.

RESULTS

195 patients were included (mean age 69.6 DS±11.2; n = 135, 69.2% men; mean BMI: 26.6 kg/m2 range 19-41) totalling n = 72 (36.8%) TEVAR, n = 107 (55.4%) FEVAR and n = 14 (7.3%) BEVAR. Patients were divided in 2 groups [obese: BMI≥30 kg/m2n = 52 (26.7%); and nonobese, BMI<30 kg/m2, n = 143 (73.3%) that statistically differed only in terms of coronary artery disease (obese 42.3% vs. 26.6% nonobese, P = 0.035) and diabetes (obese 25% vs. 12.6% nonobese, P = 0.03). No statistical differences were noted in primary technical (94.2% vs. 94.4%, P = 1.00) and clinical (92.3% vs. 95.1%, P = 0.49) success. Overall morbidity (30.8% vs. 21.1%, P = 0.16), visceral vessels instability (1.9% vs. 1.4% P = 1.00), reintervention rate within 30 days (9.6% vs. 5.6% P = 0.33), 90 days (7.7% vs. 9.8%, P = 0.78) and during follow-up (9.8% vs. 20%, P = 0.14) were comparable. No statistical difference were noted in 30-day mortality (3.8% vs. 4.9%, P = 1.00) and the 2-year follow-up survival (86.8% vs. 78.4%, P = 0.180) between the 2 groups.

CONCLUSIONS

In this series, obesity was not associated to worst clinical outcomes or higher mortality rate following TEVAR/B-FEVAR. However, considering our small patient sample, a conclusive analysis on obesity as risk factors for adverse events after endovascular treatment is not possible. A larger sample from the collaboration of multiple centers will be required to obtain definitive conclusions.

Comparison of Body Mass Index (Four Categories) to In-Hospital Outcomes in Patients Who Underwent Transcatheter Aortic Valve Implantation

Although obesity is often associated with adverse outcomes in cardiovascular diseases, studies have demonstrated a beneficial effect on patients who underwent transcatheter aortic valve implantation (TAVI), coining the term "obesity paradox." We sought to determine if the obesity paradox is valid when patients are studied in body mass index (BMI) groups versus simplified classification of obese and nonobese. We examined the National Inpatient Sample database from 2016 to 2019 for all patients who underwent TAVI >18 years of age using the International Classification of Diseases, 10th edition procedure codes. Patients were grouped by BMI categories of underweight, overweight, obese, and morbidly obese. They were compared with normal-weight patients to assess the relative risk of in-hospital mortality, cardiogenic shock, ST-elevation myocardial infarction, bleeding complications requiring transfusions, and complete heart blocks requiring permanent pacemaker. A logistic regression model was constructed to account for potential confounders. Of the 221,000 patients who underwent TAVI, 42,315 patients with appropriate BMI designation were stratified into BMI groups. Compared to the normal-weight group, overweight, obese, and morbid-obese TAVI patients were associated with a lower risk of in-hospital mortality (relative risk [RR] 0.48, confidence interval [CI] 0.29 to 0.77, p <0.001), (RR 0.42, CI 0.28 to 0.63, p <0.001), (RR 0.49, CI 0.33 to 0.71, p <0.001 respectively), cardiogenic shock (RR 0.27, CI 0.20 to 0.38, p <0.001), (RR 0.21, CI 0.16 to 0.27, p <0.001), (RR 0.21, CI 0.16 to 0.26, p <0.001), and blood transfusions (RR 0.63, CI 0.50 to 0.79, p <0.001), (RR 0.47, CI 0.39 to 0.58, p <0.001), (RR 0.61, CI 0.51 to 0.74, p <0.001). This study indicated that obese patients were at a significantly lower risk of in-hospital mortality, cardiogenic shock, and bleeding complications requiring transfusions. In conclusion, our study supported the existence of the obesity paradox in TAVI patients.

The impact of obesity on perioperative and postoperative outcomes after elective endovascular abdominal aortic aneurysm repair

BACKGROUND

Obesity is a common and growing health problem in vascular surgery patients, as it is in all patient groups. Evidence regarding body mass index (BMI) on endovascular aneurysm repair (EVAR) outcomes is not clear in the literature. We aimed to determine the impact of obesity on perioperative and midterm outcomes of elective EVAR between obese and non-obese patients.

METHODS

Under a retrospective study design, a total of 120 patients (109 males, 11 females, mean age: 74.45 ± 8.59 (53-92 years)) undergoing elective EVAR between June 2012 and May 2020 were reviewed. Patients were stratified into two groups: obese (defined as a body mass index (BMI) ≥ 30 kg/m²) and non-obese (mean BMI < 30 kg/m² (32.25 ± 1.07 kg/m² vs 25.85 ± 2.69 kg/m²)).

RESULTS

Of the 120 patients included in the study, 81 (67.5%) were defined as "nonobese," while 39 (32.5%) were obese. The mean BMI of the study group was 27.93 ± 3.78 kg/m². In obese patients, the procedure time, fluoroscopy time, and dose area product (DAP) values were longer than those of non-obese patients: 89.74 ± 20.54 vs 79.69 ± 28.77 min (p = 0.035), 33.23 ± 10.14 vs 38.17 ± 8.61 min (p = 0.01) and 133.69 ± 58.17 vs 232.56 ± 51.87 Gy.cm² (p < 0.001). Although there was no difference in sac shrinkage at 12-month follow-up, there was a significant decrease at 6-month follow-up in both groups (p = 0.017). Endoleak occurred in 17.9% (n = 7) of the obese group versus 11.1% (n = 9) of the non-obese group (p = 0.302). Iliac branch occlusion developed in four patients, 3 (3.7%) in the non-obese group and 1 (2.6%) in the obese group (p = 0.608). The all-cause mortality rate was slightly higher in the obese group; however, it did not differ between the groups (p = 0.463).

CONCLUSION

In addition to the longer procedure times, fluoroscopy times, and DAP values in obese patients, regardless of obesity, significant sac shrinkage in the first 6 months of follow-up was observed in both groups. No difference was documented with regards to mortality or morbidity following EVAR.

A Systematic Review and Meta-Analysis to Assess the Impact of Pre-existing Comorbidities on the 30-Day Readmission after Lower Extremity Bypass Surgery for Peripheral Artery Occlusive Disease

BACKGROUND

Unplanned hospital readmissions after surgical operations are considered a marker for suboptimal care during index hospitalizations and are associated with poor patient outcomes and increased healthcare resource utilization. Patients undergoing lower extremity bypass (LEB) operations for severe peripheral arterial disease (PAD) have one of the highest readmission rates, among all the vascular and nonvascular surgical operations. This review is meant to evaluate the impact of pre-existing comorbidities (diabetes mellitus (DM), chronic obstructive pulmonary disease (COPD), congestive heart failure (CHF), hypertension (HTN), and coronary artery disease (CAD))-on the 30-day readmission rates among patients who underwent LEB for severe PAD.

METHODS

The review protocol was registered to the PROSPERO database (CRD42021261067). A systematic review of the English literature was performed using PubMed, Scopus, and the Cochrane Library databases from inception till April 2022. The review was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and included only studies reporting on 30-day readmission following LEB for occlusive PAD. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach and was reported as high, moderate, or low. The risk of bias was evaluated utilizing the Risk of Bias in Nonrandomized Studies - of Interventions (ROBINS-I) tool. A pooled odds ratio (OR) for each study was computed, and a P-value of <0.05 was designated as statistically significant. Interstudy heterogeneity was evaluated by Q-metric and quantified using Higgins I² statistics.

RESULTS

Five studies reported data on 30-day readmission after LEB for occlusive PAD. A total of 19,739 patients were included. Readmission occurred among 3,559 (18%) patients. DM and COPD were reported by all 5 selected studies, and CHF and HTN were reported by 4 studies. CAD was least reported among the selected 5 pre-existing conditions, with only 2 studies mentioning it. HTN (OR, 1.35; 95% confidence interval (CI), 1.10-1.64; P ≤ 0.001; I² = 52.20%), DM (OR, 1.52; 95% CI, 1.30-1.79; P ≤ 0.001; I² = 74.51%), and CHF (OR, 1.85; 95% CI, 1.51-2.25; P ≤ 0.001; I² = 50.48%) were all found to be associated with an increased risk of 30-day readmission, while the presence of COPD (OR, 1.16; 95% CI, 0.98-1.36; P = 0.09; I² = 61.93%) and CAD (OR, 1.30; 95% CI, 0.94-1.78; P = 0.11; I² = 51.01%) was not associated with early readmission on meta-analysis of the available studies.

CONCLUSIONS

The pre-existing comorbidities HTN, DM, and CHF increase the risk of 30-day readmission after LEB for occlusive PAD. The identification of these risk factors can help stratify the patients and further guide in understanding the variety of factors that contribute in hospital readmissions.

Association Between Obesity and Outcomes Following Endovascular Aneurysm Repair

BACKGROUND

Obesity is prevalent in patients with abdominal aortic aneurysms (AAA). There is an association between increasing body mass index (BMI) and increased overall cardiovascular mortality and morbidity. This study aims to assess the difference in mortality and complication rates between normal weight (NW), overweight (OW), and obese patients undergoing endovascular aneurysm repair (EVAR) for infrarenal AAA.

METHODS

This is a retrospective analysis of consecutive patients undergoing EVAR for AAA between January 1998 and December 2019. Weight classes were defined as: BMI<18.5 kg/m², underweight; BMI 18.5-24.9 kg/m², NW; BMI 25.0-29.9 kg/m², OW; BMI 30.0-39.9 kg/m², obese; BMI>39.9 kg/m² morbidly obese. Primary outcomes were long-term all-cause mortality and freedom from reintervention. Secondary outcome was aneurysm sac regression (defined as a reduction in sac diameter of 5 mm or more). Kaplan-Meier survival estimates and mixed model analysis of variance were used.

RESULTS

The study included 515 patients (83% males, mean age 77 ± 8 years) with a mean follow-up of 3.8 ± 2.8 years. In terms of weight class, 2.1% (n = 11) were underweight, 32.4% (167) were NW, 41.6% (n = 214) were OW, 21.2% (n = 109) were obese, and 2.7% (n = 14) were morbidly obese. Obese patients were younger (mean difference -5.0 years) but had a higher prevalence of diabetes mellitus (33.3% vs. 10.6% for NW) and dyslipidemia (82.4% vs. 60.9% for NW). Obese patients had similar freedom from all-cause mortality (88%) compared to OW (78%) and NW (81%) patients. The same findings were evident for freedom from reintervention where obese (79%) was similar to OW (76%) and NW (79%). At a mean follow-up of 5.1 ± 0.4 years, sac regression was observed similarly across weight classes at 49.6%, 50.6%, and 51.8% for NW, OW, and obese, respectively (P = 0.501). There was a significant difference in mean AAA diameter pre- and post-EVAR [F(2,318) = 24.37, P < 0.001] across weight classes. NW [mean reduction 4.8 mm (2.0-7.6 mm, P < 0.001)], OW [mean reduction 3.9 mm (1.5-6.3 mm, P < 0.001)], and obese [mean reduction 5.7 mm (2.3-9.1 mm, P < 0.001)] achieved similar reductions.

CONCLUSIONS

Obesity was not associated with increased mortality or reintervention in patients undergoing EVAR. Obese patients achieved similar rates of sac regression on imaging follow-up.

Effect of Body Mass Index on Early Outcomes of Endovascular Abdominal Aortic Aneurysm Repair

BACKGROUND

This study compares the presentation, management, and outcomes of patients undergoing endovascular abdominal aortic aneurysm repair (EVAR), based on their weight status as defined by their body mass index (BMI).

METHODS

Patients with primary EVAR for ruptured and intact abdominal aortic aneurysm (AAA) were identified in the National Surgical Quality Improvement Program database (2016-2019). Patients were categorized by weight status (underweight: BMI < 18.5 kg/m², normal weight: 18.5-24.9 kg/m², overweight: 25-29.9 kg/m², Obese I: 30-34.9 kg/m², Obese II: 35-39.9 kg/m², Obese III: > 40 kg/m²). Preoperative characteristics and 30-day outcomes were compared.

RESULTS

Of 3,941 patients, 4.8% were underweight, 24.1% normal weight, 37.6% overweight, and 22.5% with Obese I, 7.8% Obese II, and 3.3% Obese III status. Underweight patients presented with larger (6.0 [5.4-7.2] cm) and more frequently ruptured (25.0%) aneurysms than normal weight patients (5.5 [5.1-6.2] cm and 4.3%, P < 0.001 for both). Pooled 30-day mortality was worse for underweight (8.5%) compared to all other weight status (1.1-3.0%, P < 0.001), but risk-adjusted analysis demonstrated that aneurysm rupture (odds ratio [OR] 15.9, 95% confidence interval [CI] 8.98-28.0) and not underweight status (OR 1.75, 95% CI 0.73-4.18) accounted for increased mortality in this population. Obese III status was associated with prolonged operative time and respiratory complications after ruptured AAA, but not 30-day mortality (OR 0.82, 95% CI 0.25-2.62).

CONCLUSIONS

Patients at either extreme of the BMI range had the worst outcomes after EVAR. Underweight patients represented only 4.8% of all EVARs, but 21% of mortalities, largely attributed to higher incidence of ruptured AAA at presentation. Severe obesity, on the other hand, was associated with prolonged operative time and respiratory complications after EVAR for ruptured AAA. BMI, as an independent factor, was however not predictive of mortality for EVAR.

Challenges in Cardiovascular Evaluation and Management of Obese Patients: JACC State-of-the-Art Review

Many unique clinical challenges accompany the diagnosis and treatment of cardiovascular disease (CVD) in people living with overweight/obesity. Similarly, physicians encounter numerous complicating factors when managing obesity among people with CVD. Diagnostic accuracy in CVD medicine can be hampered by the presence of obesity, and pharmacological treatments or cardiac procedures require careful adjustment to optimize efficacy. The obesity paradox concept remains a source of confusion within the clinical community that may cause important risk factors to go unaddressed, and body mass index is a misleading measure that cannot account for body composition (eg, lean mass). Lifestyle modifications that support weight loss require long-term commitment, but cardiac rehabilitation programs represent a potential opportunity for structured interventions, and bariatric surgery may reduce CVD risk factors in obesity and CVD. This review examines the key issues and considerations for physicians involved in the management of concurrent obesity and CVD.

Underweight predicts extubation failure after planned extubation in intensive care units

BACKGROUND

Body weight is associated with different physiological changes and the association between weight and mortality in critical care setting had been discussed before. In this study, we investigated the linkage between underweight and post-extubation failure in mechanical ventilated patients in critical setting.

METHODS

This is a retrospective cohort study including patients who were admitted to medical or surgical intensive care units (ICU) between June 2016 and July 2018 and had received endotracheal intubation for more than 72 hours. Those who passed spontaneous breathing trial and underwent a planned extubation were enrolled. Extubation failure was defined as those who required reintubation within the first 72 hours for any reasons. The probability of extubation failure was calculated. Demographic and clinical characteristics were recorded. Multivariate logistic regression models were then used to determine the potential risk factors associated with extubation failure.

RESULTS

Overall, 268 patients met the inclusion criteria and were enrolled in our study for analysis. The median age of included patients was 67 years (interquartile range, 55-80 years) with 65.3% being male; 63.1% of the patients were included from medical ICU. The proportion of extubation failure in our cohort was 7.1% (19/268; 95% confidence interval [CI], 4.3-10.9%). Overall, underweight patients had the highest risk of extubation failure (8/50), as compared with normoweight (9/135) and overweight patients (2/83). In the multivariate analysis, being underweight (adjust OR [aOR], 3.80, compared to normoweight; 95% CI, 1.23-11.7) and lower maximal inspiratory airway pressure (aOR per one cmH2O decrease, 1.05; 95% CI 1.00-1.09) remained significantly associated with extubation failure.

CONCLUSION

In our study, being underweight and lower maximal inspiratory airway pressure was associated with post-extubation respiratory failure after a planned extubation.

Effect of low body mass index on clinical recovery after fusion surgery for osteoporotic vertebral fracture: A retrospective, multicenter study of 237 cases

A retrospective multicenter study. Body mass index (BMI) is recognized as an important determinant of osteoporosis and spinal postoperative outcomes; however, the specific impact of BMI on surgery for osteoporotic vertebral fractures (OVFs) remains inconclusive. This retrospective multicenter study investigated the impact of BMI on clinical outcomes following fusion surgery for OVFs. 237 OVF patients (mean age, 74.3 years; 48 men and 189 women) with neurological symptoms who underwent spinal fusion were included in this study. Patients were grouped by World Health Organization BMI categories: low BMI (<18.5 kg/m2), normal BMI (≥18.5 and <25 kg/m2), and high BMI (≥25 kg/m2). Patients' backgrounds, surgical method, radiological findings, pain measurements, activities of daily living (ADL), and postoperative complications were compared after a mean follow-up period of 4 years. As results, the proportion of patients able to walk independently was significantly smaller in the low BMI group (75.0%) compared with the normal BMI group (89.9%; P = .01) and the high BMI group (94.3%; P = .04). Improvement in the visual analogue scale for leg pain was significantly less in the low BMI group than the high BMI group (26.7 vs 42.8 mm; P = .046). Radiological evaluation, the Frankel classification, and postoperative complications were not significantly different among all 3 groups. Improvement of pain intensity and ADL in the high BMI group was equivalent or non-significantly better for some outcome measures compared with the normal BMI group. Leg pain and independent walking ability after fusion surgery for patients with OVFs improved less in the low versus the high BMI group. Surgeons may want to carefully evaluate at risk low BMI patients before fusion surgery for OVF because poor clinical results may occur.

Body mass index and early outcomes after carotid endarterectomy

As the existing data on the correlation of adiposity with adverse outcomes of carotid endarterectomy (CEA) are inconsistent, the aim of the present study is to examine the correlation of an increased body mass index with 30-day complications after carotid endarterectomy. The cohort study comprises 1586 CEAs, performed at the Clinic for Vascular Surgery in Belgrade, from 2012-2017. Out of them, 550 CEAs were performed in patients with normal body mass index (18.5-24.9), 750 in overweight (25.0-29.9), and 286 in obese (≥30) patients. The association of overweight and obesity with early outcomes of carotid endarterectomy was assessed using univariate and multivariate logistic regression analysis. Overweight patients, in whom CEAs were performed, were significantly more frequently males, compared to normal weight patients-Odds Ratio (OR) 1.51 (95% confidence interval- 1.19-1.89). Moreover, overweight patients significantly more frequently had non-insulin-dependent diabetes mellitus-OR 1.44 (1.09-1.90), and more frequently used ACEI in hospital discharge therapy-OR 1.41 (1.07-1.84) than normal weight patients. Additionally, the CEAs in them were less frequently followed by bleedings-OR 0.37 (0.16-0.83). Compared to normal weight patients, obese patients were significantly younger-OR 0.98 (0.96-0.99), and with insulin-dependent and non-insulin-dependent diabetes mellitus-OR 1.83 (1.09-3.06) and OR 2.13 (1.50-3.01) respectively. They also more frequently had increased triglyceride levels-OR 1.36 (1.01-1.83), and more frequently used oral anticoagulants in therapy before the surgery-OR 2.16 (1.11-4.19). According to the results obtained, overweight and obesity were not associated with an increased death rate, transient ischemic attack (TIA), stroke, myocardial infarction, or with minor complications, and the need for reoperation after carotid endarterectomy. The only exception was bleeding, which was significantly less frequent after CEA in overweight compared to normal weight patients.

The impact of body mass index on mortality rates of hip fracture patients: a systematic review and meta-analysis

Obesity has been recognized as a global epidemic as approximately one-third of the world's population. Findings on early and late mortality rates between obese, overweight, and underweight vs normal body mass index (BMI) patients confirm that the obese and overweight patients were found to have lower risk and underweight patients were found to have increased risk of mortality as compared to normal weighted patients. It is unclear if the "obesity paradox" exists with survival outcomes of hip fracture patients. We hereby reviewed early (in-hospital and 30-day mortality) and late mortality (≥ 1-year) rates between obese, overweight, and underweight vs normal body mass index (BMI) patients with hip fractures. PubMed, Embase, ScienceDirect, CENTRAL, and Google Scholar were searched for studies reporting mortality rates of hip fracture patients based on BMI. We pooled crude and adjusted mortality rates in a random-effects model. Eleven studies were included. Meta-analysis indicated significantly reduced risk of early (RR: 0.64 95% CI: 0.59, 0.69 I² = 0% p < 0.00001) and late mortality rates (RR: 0.78 95% CI: 0.67, 0.91 I² = 93% p = 0.002) in obese vs normal BMI patients. Meta-analysis failed to demonstrate any statistically significant difference in early mortality (RR: 0.90 95% CI: 0.54, 1.53 I² = 44% p = 0.71) but significantly reduced risk of late mortality in overweight vs normal BMI patients (RR: 0.85 95% CI: 0.73, 0.93 I² = 84% p = 0.003). Scarce data suggested increased risk of early (RR: 1.44 95% CI: 1.08, 1.93 I² = 26% p = 0.01) and late mortality (RR: 1.23 95% CI: 1.08, 1.41 I² = 7% p = 0.002) in underweight vs normal BMI patients. Adjusted data corroborated the reduced risk of mortality in overweight (HR: 0.78 95% CI: 0.74, 0.83 I² = 0% p < 0.0001) and obese patients (HR: 0.66 95% CI: 0.60, 0.73 I² = 0% p < 0.0001). Our results indicate that the "obesity paradox" exists with survival outcomes of hip fracture patients. Obese and overweight patients were found to have lower risk and underweight patients were found to have increased risk of mortality as compared to normal weighted patients.

The Effect of Smoking Status on Perioperative Morbidity and Mortality after Open and Endovascular Abdominal Aortic Aneurysm Repair

OBJECTIVES

This study quantifies the extent to which active tobacco smoking is deleterious towards outcomes following open and endovascular AAA repair.

METHODS

Open and endovascular abdominal aortic aneurysm (AAA) repairs between January 2003 and June 2020 in the Vascular Quality Initiative (VQI) were queried. Rupture, symptomatic status, and lack of 90 day follow up were exclusions. Patients were then placed into one of six groups : open AAA with active smoking (n=3788); open AAA with prior smoking (n=4614); open AAA never smokers (817); endovascular AAA active smokers (n=14173); endovascular AAA former smokers (n=25,831); and, endovascular AAA never smokers (n=6064). Comparison of baseline characteristics, co-morbidities, and adverse outcomes across each of the 6 cohorts was performed with open AAA in active smokers serving as the reference. Sub-analysis investigating open AAA repair in active smokers relative to open AAA in patients confirmed in VQI to have quit smoking between 30 and 90 days before surgery was performed. Smoking cessation for a minimum of 30 days before surgery was required to fall into the former smoker category.

RESULTS

In comparing open AAA in active smokers to open AAA in former and never smokers, the active smokers experienced significantly higher rates of pneumonia (P<.001). Combined additive morbidity and mortality was highest (54%) in active smokers (P<.001 relative to all cohorts other than open AAA former smokers P=.21). Smoking status did not impact morbidity or mortality incidence across individuals undergoing EVAR. Binary logistic regression for all AAA patients (open and endovascular combined) revealed those with any history of smoking to be more likely to experience 90 day mortality (adjusted OR 2.5 (2.2-2.9), P<.001) relative to never-smokers. Active smokers were similarly more likely to experience 90 day mortality than prior/never smokers combined (OR 1.23 (1.07-1.38), P<.001). Mortality within 90 days was significantly more likely (P<.001) with aging, female gender, larger aneurysms, preoperative history of congestive heart failure, chronic obstructive pulmonary disease, chronic renal insufficiency, peripheral artery disease, body mass index under 20 and over 35 mg/kg². Diabetes and coronary artery disease were also associated with 90 day mortality (P= .045 and .049 respectively). Quitting smoking between 30 and 90 days before open repair reduced combined additive morbidity and mortality relative to active smokers (OR 1.34, P =.038).

CONCLUSIONS

Smoking cessation 30 days before open AAA repair reduces perioperative morbidity and mortality. Smoking status does not impact morbidity and mortality in patients undergoing endovascular AAA repair. When combining all patients (open and endovascular), higher rates of 90 day mortality are associated with any history of smoking, aging, female gender and advanced pre-existing co-morbidities on multivariable analysis.

Underweight patients are the highest risk body mass index group for perioperative adverse events following stand-alone anterior lumbar interbody fusion

BACKGROUND CONTEXT

Prior studies investigating the association between Body Mass Index (BMI) and patient outcomes following spine surgery have had inconsistent conclusions, likely owing to insufficient power, confounding variables, and varying definitions and cutoffs for BMI categories (eg, underweight, overweight, obese, etc.). Further, few studies have considered outcomes among low BMI cohorts.

PURPOSE

The current study analyzes how anterior lumbar interbody fusion (ALIF) perioperative outcomes vary along the BMI spectrum, using World Health Organization (WHO) categories of BMI.

STUDY DESIGN/SETTING

A retrospective cohort study.

PATIENT SAMPLE

Patients undergoing stand-alone one or two-level anterior lumbar interbody fusion (ALIF) found in the 2005-2018 American College of Surgeons National Surgical Quality Improvement Program (NSQIP) databases.

OUTCOME MEASURES

Thirty-day adverse events, hospital readmissions, post-operative infections, and mortality.

METHODS

Stand-alone one or two-level ALIF surgical cases were identified and extracted from the 2005-2018 National Surgical Quality Improvement Program (NSQIP) database. Posterior cases and those primary diagnoses of trauma, tumor, infection, or emergency presentation were excluded. Patients were then binned into WHO guidelines of BMI. The incidence of adverse outcomes within 30-day post-operation was defined. Odds ratios of adverse outcomes, normalized to the average risk of normal-weight subjects (BMI 18.5-24.9 kg/m³), were calculated. Multivariate analysis was then performed controlling for patient factors.

RESULTS

In total, 13,710 ALIF patients were included in the study. Incidence of adverse events was elevated in both the underweight (BMI<18.5 kg/m³) and super morbidly obese (>50 kg/m³), however, multivariate risks for adverse events and postoperative infection were elevated for underweight patients beyond those found in any other BMI category. No effect was noted in these identical variables between normal, overweight, obese class 1, or even obese class 2 patients. Multivariate analysis also found overweight patients to show a slightly protective trend against mortality while the super morbidly obese had elevated odds.

CONCLUSIONS

Underweight patients are at greater odds of experiencing postoperative adverse events than normal, overweight, obese class 1, or even obese class 2 patients. The present study identifies underweight patients as an at-risk population that should be given additional consideration by health systems and physicians, as is already done for those on the other side of the BMI spectrum.

Does the "obesity paradox" exist after transcatheter aortic valve implantation?

Background

Transcatheter aortic valve implantation (TAVI) for symptomatic aortic stenosis is considered a minimally invasive procedure. Body mass index (BMI) has been rarely evaluated for pulmonary complications after TAVI. This study aimed to assess the influence of BMI on pulmonary complications and other related outcomes after TAVI.

Methods

The clinical data of 109 patients who underwent TAVI in our hospital from May 2018 to April 2021 were retrospectively analyzed. Patients were divided into three groups according to BMI: low weight (BMI < 21.9 kg/m², n = 27), middle weight (BMI 21.9–27.0 kg/m², n = 55), and high weight (BMI > 27.0 kg/m², n = 27); and two groups according to vascular access: through the femoral artery (TF-TAVI, n = 94) and through the transapical route (TA-TAVI, n = 15). Procedure endpoints, procedure success, and adverse outcomes were evaluated according to the Valve Academic Research Consortium (VARC)-2 definitions.

Results

High-weight patients had a higher proportion of older (p < 0.001) and previous percutaneous coronary interventions (p = 0.026), a higher percentage of diabetes mellitus (p = 0.026) and frailty (p = 0.032), and lower glomerular filtration rate (p = 0.024). Procedure success was similar among the three groups. The 30-day all-cause mortality of patients with low-, middle-, and high weights was 3.7% (1/27), 5.5% (3/55), and 3.7% (1/27), respectively. In the multivariable analysis, middle- and high-weight patients exhibited similar overall mortality (middle weight vs. low weight, p = 0.500; high weight vs. low weight, p = 0.738) and similar intubation time compared with low-weight patients (9.1 ± 7.3 h vs. 8.9 ± 6.0 h vs. 8.7 ± 4.2 h in high-, middle-, and low-weight patients, respectively, p = 0.872). Although high-weight patients had a lower PaO₂/FiO₂ ratio than low-weight patients at baseline, transitional extubation, and post extubation 12th hour (p = 0.038, 0.030, 0.043, respectively), there were no differences for post extubation 24th hour, post extubation 48th hour, and post extubation 72nd hour (p = 0.856, 0.896, 0.873, respectively). Chronic lung disease [odds ratio (OR) 8.038, p = 0.001] rather than high weight (OR 2.768, p = 0.235) or middle weight (OR 2.226, p = 0.157) affected postoperative PaO₂/FiO₂ after TAVI.

Conclusions

We did not find the existence of an obesity paradox after TAVI. BMI had no effect on postoperative intubation time. Patients with a higher BMI should be treated similarly without the need to deliberately extend the intubation time for TAVI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-022-01910-x.

Comparison of the perioperative outcomes between robotic-assisted thoracic surgery and video-assisted thoracic surgery in non-small cell lung cancer patients with different body mass index ranges

Background

Non-small cell lung cancer (NSCLC) is the most common malignancy and one of the most common causes of cancer-related death worldwide. Robotic-assisted thoracic surgery (RATS) has gradually become a prevalent surgical method for patients with NSCLC. Previous studies have found that body mass index (BMI) is associated with postoperative outcomes. This study aimed to investigate the effectiveness of RATS compared to video-assisted thoracic surgery (VATS) in the treatment of NSCLC with different BMI, in terms of perioperative outcomes.

Methods

The baseline and perioperative data, including BMI, of 849 NSCLC patients who underwent minimally invasive anatomic lung resections from August 2020 to April 2021 were retrospectively collected and analyzed. Propensity score matching analysis was applied to minimize potential bias between the two groups (VATS and RATS), and the perioperative outcomes were compared. Subgroup analysis was subsequently performed.

Results

Compared to VATS, RATS had more lymph nodes dissected {9 [inter-quartile range (IQR), 6–12] vs. 7 (IQR, 6–10), P<0.001}, a lower estimated bleeding volume [40 (IQR, 30–50) vs. 50 (IQR, 40–60) mL, P<0.001], and other better postoperative outcomes, but a higher cost of hospitalization [¥83,626 (IQR, 77,211–92,686) vs. ¥75,804 (IQR, 66,184–83,693), P<0.001]. Multivariable logistic regression analysis indicated that RATS (P=0.027) and increasing BMI (P=0.030) were associated with a statistically significant reduction in the risk of postoperative complications. Subgroup analysis indicated that the advantages of RATS may be more obvious in patients with a BMI of 24–28 kg/m², in which the RATS group had more lymph nodes dissected [9 (IQR, 6–12) vs. 7 (IQR, 5–10), P<0.001] and a decreased risk of total postoperative complications [odds ratio (OR), 0.443; 95% confidence interval (CI), 0.212–0.924; P=0.030] compared to the VATS group.

Conclusions

Both, RATS and VATS can be safely applied for patients with NSCLC. Perioperative outcome parameters indicate advantages for RATS, however at a higher cost of hospitalization. The advantages of RATS might be more obvious in patients with a BMI of 24–28 kg/m².

Clinical features and prognosis of patients with and without diabetes mellitus undergoing endovascular aortic aneurysm repair

BACKGROUND

This study aimed to compare the clinical features and prognoses of patients with and without diabetes mellitus (DM) who underwent endovascular repair for aortic aneurysm (AA).

METHODS

We analyzed the clinical database of a prospective multicenter study, registering 929 patients who underwent their first endovascular AA repair in Japan between January 2016 and June 2018. The baseline characteristics and prognoses (including all-cause mortality and cardiovascular events) after repair were compared between the DM and non-DM groups. Prognoses were also compared between the groups after propensity score matching.

RESULTS

In total, 226 patients (24.3%) had DM. Compared with non-DM patients, DM patients had higher pack-years of smoking (P = 0.011), higher body mass index (P = 0.009), lower high-density lipoprotein cholesterol levels (P = 0.038), higher triglyceride levels (P = 0.025), and lower left ventricular ejection fraction (P = 0.005). Meanwhile, the low-density lipoprotein cholesterol and blood pressure levels showed no significant intergroup difference (all P > 0.05). DM patients had a higher prevalence of myocardial infarction (P = 0.016), history of coronary revascularization (P = 0.015), and lower extremity artery disease (P = 0.019). Lesion characteristics and procedures were similar between the groups (all P > 0.05). DM patients had a higher risk of all-cause mortality and cardiovascular events than non-DM patients (both P < 0.001). Subsequent propensity score matching also demonstrated that DM patients had a significantly lower rate of overall survival (P = 0.001) and freedom from cardiovascular events (P = 0.010). The Kaplan-Meier estimates at 1 year for the overall survival were 85.6% (95% confidence interval [CI], 80.9% to 90.5%) and 94.3% (95% CI, 91.7% to 97.0%) for patients with and without DM, respectively. The corresponding estimates for freedom from cardiovascular events were 79.8% (95% CI, 74.5% to 85.5%) and 87.7% (95% CI, 84.2% to 91.3%), respectively.

CONCLUSIONS

Among patients undergoing endovascular AA repair, those with DM had more cardiovascular risk factors. DM patients had a higher incidence rate of all-cause mortality and cardiovascular events. Matching analysis indicated that DM per se would be a risk factor for poor prognoses after AA repair.

Impact of body mass index on the outcome of elderly patients treated with transcatheter aortic valve implantation

Underweight or overweight patients with cardiovascular diseases are associated with different outcomes. However, the data on the relation between body mass index (BMI) and outcomes after transcatheter aortic valve implantation (TAVI) are not homogeneous. The aim of this study was to assess the role of low BMI on short and long-term mortality in real-world patients undergoing TAVI. We retrospectively included patients undergoing TAVI for severe aortic valve stenosis. Patients were classified into three BMI categories: underweight (< 20 kg/m²), normal weight (20-24.9 kg/m²) and overweight/obese (≥ 25 kg/m²). Our primary endpoint was long-term all-cause mortality. The secondary endpoint was 30-day all-cause mortality. A total of 794 patients were included [mean age 82.3 ± 5.3, 53% females]. After a median follow-up of 2.2 years, all-cause mortality was 18.1%. Patients in the lowest BMI group showed a higher mortality rate as compared to those with higher BMI values. At the multivariate Cox regression analysis, as compared to the normal BMI group, BMI < 20 kg/m² was associated with long-term mortality independently of baseline risk factors and postprocedural adverse events (hazard ratio [HR] 2.29, 95% confidence interval [CI] 1.30-4.03] and HR 2.61, 95% CI 1.48-4.60, respectively). The highest BMI values were found to be protective for both short- and long-term mortality as compared to lower BMI values even after applying the same adjustments. In our cohort, BMI values under 20 kg/m² were independent predictors of increased long-term mortality. Conversely, the highest BMI values were associated with lower mortality rates both at short- and long-term follow-up.

Burn Outcomes at Extremes of Body Mass Index- Underweight is as problematic as Morbid Obesity

Limited evidence suggests that obesity adversely affects burn outcomes. However, the impacts of body mass index (BMI) across the continuum has not been fully characterized. Therefore, we aimed to characterize outcomes after burn injury across the BMI continuum. We hypothesized that 'normal' BMI (18.5-24.9) would have the lowest mortality and complication rates. The US National Trauma Data Bank (NTDB) was queried for adult burn-injured patients from 2007-2015. Admission BMI was calculated and grouped according to World Health Organization (WHO) classification. The primary outcome was in-hospital mortality. Secondary outcomes of time to wound closure, length of stay (LOS), and inpatient complications were similarly assessed. Of the 116,008 burn patient encounters that were identified, 7,243 underwent at least one operation for wound closure. Mortality was lowest in the overweight (p=0.039) and obese I cohorts (BMI 25-29.9, 30.0-34.9) at 2.9% and increased in both directions of the BMI continuum to 4.1% in the underweight (p=0.032) and 5.1% in the morbidly obese (class III) group (p=0.042). Time to final wound closure was longest in the two BMI extremes. BMI >40 was associated with increased ICU days, ventilator days, renal and cardiac complications. BMI <18.5 had increased hospital days and rates of sepsis. Aberrations in metabolism associated with both increases and decreases of body weight may cause pathophysiologic changes that lead to worsened outcomes in burn-injured patients. In addition to morbidly obese patients, underweight patients also experience increased burn-related death and complications. In contrast, overweight BMI patients may have greater physiologic reserves without the burden of obesity or sarcopenia.

New Measures, Old Conclusions: Obesity Does Not Worsen Outcomes after Elective Abdominal Aortic Aneurysm Repair

Background  The “obesity paradox,” whereby the body mass index (BMI) mortality curve is “U-shaped,” is a well-studied phenomenon in vascular surgery. However, there has been an overreliance on BMI as the measure of obesity, which has shown to poorly correlate with clinical outcomes. Robust measures such as waist-hip ratio (WHR) have been suggested as a more accurate marker reflecting central obesity.

Objectives  The objectives of this study were to evaluate the correlation between BMI and WHR on postoperative morbidity and mortality after elective abdominal aortic aneurysm (AAA) repair.

Methods  Data were collected from the Leeds Vascular Institute between January 2006 and December 2016. The primary outcome was mortality and secondary outcomes included length of stay (LOS) and all-cause readmission. Binary logistic regression, linear regression, and correlation analysis were used to identify associations between BMI and WHR in relation to outcome measures.

Results  After exclusions, 432 elective AAA repairs (281 open surgical repair [OSR] and 151 endovascular aneurysm repairs [EVARs]) were identified to be eligible for the study. The combined 30-day and 4-year mortality was 1.2 and 20.1%, respectively. The 30-day readmission rate was 3.9% and the average LOS was 7.33 (standard deviation 18.5) days. BMI data was recorded for 275 patients (63.7%) and WHR for 355 patients (82.2%). Logistic regression analysis highlighted no association between BMI and WHR with mortality, readmission, or LOS following OSR or EVAR.

Conclusion  The results of this study suggest patients should not be denied treatment for AAA based on obesity alone.

Short-term Mortality and Postoperative Complications of Abdominal Aortic Aneurysm Repair in Obese versus Non-obese Patients

Background

Obesity is a risk factor not only for abdominal aortic aneurysm (AAA) but also for complications after vascular surgery. This study was to determine the effect of obesity on short-term mortality and post-intervention complications after AAA repair.

Methods

A systematic review and meta-analysis were performed. A systematic search was performed in PubMed; the articles describing the differences in post-intervention complications after open or endovascular repair of an AAA between obese and non-obese patients were selected. The primary outcome was short-term mortality defined as in-hospital mortality or mortality within 30 days after AAA repair. The secondary outcomes were cardiac complications, pulmonary failure, renal failure, and wound infections. The meta-analysis was performed using OpenMeta.

Results

Four articles were included in the meta-analysis; these articles included 35,989 patients of which 10,917 (30.3%) were obese. The meta-analysis showed no significant differences for short-term mortality (odds ratio [OR], 0.85; 95% confidence interval [CI], 0.69-1.04). Also, no significant difference was found in pulmonary failure (OR, 1.09; 95% CI, 0.85-1.42). However, obese patients were less likely to suffer from cardiac complications (OR, 0.73; 95% CI, 0.55-0.96). Nevertheless, there was a significantly higher risk of renal failure (OR, 1.16; 95% CI, 1.05-1.30) and wound infections (OR, 1.92; 95% CI, 1.55-2.38) in obese patients.

Conclusion

Obesity is not a risk factor for short-term mortality after AAA repair compared to non-obesity. Moreover, obese patients suffer less from cardiac complications than non-obese patients.

A systematic review and meta-analysis evaluating the impact of obesity on outcomes of abdominal aortic aneurysm treatment

OBJECTIVE

We sought to evaluate the impact of obesity on perioperative mortality and complication rates in patients undergoing endovascular aortic repair (EVAR) and open surgical repair (OSR) for abdominal aortic aneurysms (AAA).

METHODS

A systematic review of all studies reporting AAA treatment perioperative (30 day) outcomes in obese patients (body mass index ≥30 kg/m²). The primary outcome was 30 day mortality. Secondary outcomes included: cardiac complications, respiratory complications, wound complication, renal complications, and neurological complications at 30 days. These outcomes were pooled for meta-analysis. Analysis first compared obese versus nonobese patients undergoing EVAR and OSR then compared EVAR to OSR in obese patients.

RESULTS

We identified 7 observational studies with 14,971 patients (11,743 EVAR, 3228 OSR). Obese patients undergoing EVAR had lower 30 day mortality (1.5%) compared to nonobese patients (2.2%) (OR 0.69; 95% CI 0.50-0.96; p=0.03; I²= 0%; Grade of evidence: low). In OSR, obese patients (5.0%) had similar 30 day mortality to nonobese patients (5.7%) (OR 0.92; 95% CI 0.70-1.20; p=0.54; I²=0%; Grade of evidence: low). Wound complications were higher in obese patients undergoing OSR (OR 2.30; 95% CI 1.74-3.06; p<0.001; I²=0%; Grade of evidence: low). EVAR was associated with a lower 30 day mortality (1.5%) compared to OSR (5.0%) in obese patients (OR 0.23; 95% CI 0.12-0.46; p<0.001; I²= 38%; Grade of evidence: low). Cardiac, respiratory, wound, renal and neurological complications were also reduced in EVAR.

CONCLUSIONS

Obese patients have lower 30 day mortality in EVAR compared to nonobese patients. In OSR, obese patients had similar 30 day mortality but higher wound complications compared to nonobese patients. Obese patients otherwise have similar cardiopulmonary complication rates compared to nonobese patients in both EVAR and OSR. EVAR offers lower 30 day mortality and morbidity compared to OSR in obese patients. This study suggests that EVAR is superior to OSR in obese patients.

Endovascular Aortic Repair in Patients of Advanced Age

PURPOSE

Treatment decisions for the elderly with abdominal aortic aneurysms (AAAs) are challenging. With advancing age, the risk of endovascular aneurysm repair (EVAR) increases while life expectancy decreases, which may nullify the benefit of EVAR. The purpose of this study was to quantify the impact of EVAR on 1-year mortality in patients of advanced age.

MATERIALS AND METHODS

The 2003-2020 Vascular Quality Initiative Database was utilized to identify patients who underwent EVAR for AAAs. Patients were included if they were 80 years of age or older. Exclusions included non-elective surgery or missing aortic diameter data. Predicted 1-year mortality of untreated AAAs was calculated based on a validated comorbidity score that predicts 1-year mortality (Gagne Index, excluding the component associated with AAAs) plus the 1-year aneurysm-related mortality without repair. The primary outcome for the study was 1-year mortality.

RESULTS

A total of 11 829 patients met study criteria. The median age was 84 years [81, 86] with 9014 (76.2%) being male. Maximal AAA diameters were apportioned as follows: 39.6% were <5.5 cm, 28.6% were 5.5-5.9 cm, 21.3% were 6.0-6.9 cm, and 10.6% were ≥7.0 cm. The predicted 1-year mortality rate without EVAR was 11.9%, which was significantly higher than the actual 1-year mortality rate with EVAR (8.2%; p<0.001). The overall rate of perioperative MACE was 4.4% (n = 516). Patients with an aneurysm diameter <5.5cm had worse actual 1-year mortality rates with EVAR compared to predicted 1-year mortality rates without EVAR. In contrast, those with larger aneurysms (≥5.5cm) had better actual 1-year mortality rates with EVAR. The benefit from EVAR for those with Gagne Indices 2-5 was largely restricted to those with AAAs ≥ 7.0cm; whereas those with Gagne Indices 0-1 experience a survival benefit for AAAs larger than 5.5 cm.

CONCLUSION

The current data suggest that EVAR decreases 1-year mortality rates for patients of advanced age compared to non-operative management in the elderly. However, the survival benefit is largely limited to those with Gagne Indices 0-1 with AAAs ≥ 5.5 cm and Gagne Indices 2-5 with AAAs ≥ 7.0 cm. Those of advanced age may benefit from EVAR, but realizing this benefit requires careful patient selection.

Association of body mass index with outcomes after thoracic endovascular aortic repair in the vascular quality initiative

OBJECTIVE

Although several studies have evaluated the impact of obesity on outcomes after abdominal aortic aneurysm repair, literature examining this association in thoracic endovascular aortic repair (TEVAR) is sparse. Here, we use a multi-institutional, international database to assess the role of body mass index (BMI) on adverse outcomes in patients who underwent TEVAR for descending thoracic aortic aneurysms (DTAA) and type B dissections (TBD).

METHODS

A retrospective review of all patients who underwent TEVAR for DTAA or TBD from August 2014 to August 2020 was performed. Patients who were underweight (BMI <18.5 kg/m²) or obese (BMI ≥30 kg/m²) were compared with those of normal weight (≥18.5 to <30 kg/m²). Adjustment for confounding was done with multivariable logistic regression or Cox proportional hazards regression as appropriate for studying postoperative or 1-year outcomes. Primary outcomes were 30-day and 1-year mortality. Other outcomes included any postoperative complication, stroke, and spinal cord ischemia.

RESULTS

A total of 3423 participants were included in the study, of whom 3.3% (n = 113) were underweight, 65.9% (n = 2253) had normal weight, and 30.8% (n = 1053) were obese. Compared with normal weight, there was no significant difference in 30-day mortality in underweight patients (odds ratio [OR], 1.81; 95% confidence interval [CI], 0.80-4.14; P = .156). Obese patients who underwent TEVAR for TBD had a 2.7-fold increase in the odds of 30-day mortality compared with normal weight (OR, 2.67; 95% CI, 1.52-4.68; P = .001). Obese and normal weight patients with DTAA had equivalent odds of 30-day mortality (OR, 1.32; 95% CI, 0.79-2.23; P = .292). The adjusted hazard of 1-year mortality was 2-fold higher in underweight patients compared with normal weight (hazard ratio, 2.15; 95% CI, 1.41-3.29; P < .001), driven by a higher risk of mortality among patients with thoracic aortic aneurysm (OR, 2.62; 95% CI, 1.63-4.21; P < .001). There was no significant difference in 1-year mortality risk between normal weight and obesity in both DTAA (OR, 0.77; 95% CI, 0.54-1.09; P = .146) and TBD (OR, 1.26; 95% CI, 0.85-1.86; P = .248).

CONCLUSIONS

In this study, obese patients who underwent TEVAR for DTAA had comparable 30-day and 1-year mortality risk as normal weight individuals. Obese patients who underwent TEVAR for TBD demonstrated a 2.7-fold increase in the odds of 30-day mortality, but equivalent mortality risk as normal weight patients at 1 year. TEVAR represents a safe minimally invasive option for treatment of DTAA in obese patients. Future work should be directed toward minimizing perioperative mortality among patients with TBD to optimize TEVAR outcomes.

The Association of Body Mass Index with Outcomes after Carotid Endarterectomy

BACKGROUND

Patients who are obese or underweight are traditionally at higher risk for perioperative morbidity and mortality. The effect of body mass index (BMI) on outcomes after carotid endarterectomy (CEA) is unclear. Our goal was to analyze the association of BMI with perioperative and long-term outcomes after elective CEA.

METHODS

The Vascular Quality Initiative (VQI) database was queried from 2003-2018 for patients undergoing elective CEAs. Patients were categorized into 5 BMI cohorts - underweight (UW, BMI < 18.5 kg/m²), normal weight (NW, BMI 18.5-24.9 kg/m²), overweight (OW, BMI 25-29.9 kg/m²), obese (OB, BMI 30-39.9 kg/m²), and morbidly obese (MO, BMI ≥ 40 kg/m²). Perioperative and long-term outcomes were assessed with univariable and multivariable analyses.

RESULTS

There were 89,079 patients included: 2% UW, 26% NW, 38.4% OW, 29.9% OB, and 3.6% MO. Overall, the mean age was 70.6 years, 60% were male, and 91.8% were of white race. There were significant differences among the BMI cohorts in regards to age, sex, smoking status, and comorbidities (all P < 0.05). For perioperative outcomes, the BMI cohorts differed significantly in reoperation for bleeding and 30-day mortality. On multivariable analysis, BMI was not associated with stroke or perioperative mortality. MO was associated with perioperative cardiac complications (Odds Ratios [OR] 1.26, 95% CI 1-1.57, P = 0.05). UW status was associated with increased return to the operating room (OR 1.89, 95% confidence interval [95% CI] 1.28-2.78, P = 0.001), 30-day mortality (OR 1.68, 95% CI 1-2.86, P =0.05), 1-year mortality (Hazard ratio [HR] 1.37, 95% CI 1.08-1.74, P = 0.01), and 5-year mortality (HR 1.22, 95% CI 1.06-1.41, P =0.005).

CONCLUSIONS

BMI status was not associated with perioperative stroke, cranial nerve injury, or surgical site infections. Patients with MO had higher perioperative cardiac complications. UW patients have lower short and long-term survival and should be a focus for long-term targeted risk factor stratification and modification.

Isolated severe blunt traumatic brain injury: effect of obesity on outcomes

OBJECTIVE

Obesity has been widely reported to confer significant morbidity and mortality in both medical and surgical patients. However, contemporary data indicate that obesity may confer protection after both critical illness and certain types of major surgery. The authors hypothesized that this "obesity paradox" may apply to patients with isolated severe blunt traumatic brain injuries (TBIs).

METHODS

The Trauma Quality Improvement Program (TQIP) database was queried for patients with isolated severe blunt TBI (head Abbreviated Injury Scale [AIS] score 3-5, all other body areas AIS < 3). Patient data were divided based on WHO classification levels for BMI: underweight (< 18.5 kg/m2), normal weight (18.5-24.9 kg/m2), overweight (25.0-29.9 kg/m2), obesity class 1 (30.0-34.9 kg/m2), obesity class 2 (35.0-39.9 kg/m2), and obesity class 3 (≥ 40.0 kg/m2). The role of BMI in patient outcomes was assessed using regression models.

RESULTS

In total, 103,280 patients were identified with isolated severe blunt TBI. Data were excluded for patients aged < 20 or > 89 years or with BMI < 10 or > 55 kg/m2 and for patients who were transferred from another treatment center or who showed no signs of life upon presentation, leaving data from 38,446 patients for analysis. Obesity was not found to confer a survival advantage on univariate analysis. On multivariate analysis, underweight patients as well as obesity class 1 and 3 patients had a higher rate of mortality (OR 1.86, 95% CI 1.48-2.34; OR 1.18, 95% CI 1.01-1.37; and OR 1.41, 95% CI 1.03-1.93, respectively). Increased obesity class was associated with an increased risk of respiratory complications (obesity class 1: OR 1.19, 95% CI 1.03-1.37; obesity class 2: OR 1.30, 95% CI 1.05-1.62; obesity class 3: OR 1.55, 95% CI 1.18-2.05) and thromboembolic complications (overweight: OR 1.43, 95% CI 1.16-1.76; obesity class 1: OR 1.45, 95% CI 1.11-1.88; obesity class 2: OR 1.55, 95% CI 1.05-2.29) despite a decreased risk of overall complications (obesity class 2: OR 0.82, 95% CI 0.73-0.92; obesity class 3: OR 0.83, 95% CI 0.72-0.97). Underweight patients had a significantly increased risk of overall complications (OR 1.39, 95% CI 1.24-1.57).

CONCLUSIONS

Although there was an obesity-associated decrease in overall complications, the study data did not demonstrate a paradoxical protective effect of obesity on mortality after isolated severe blunt TBI. Obese patients with isolated severe blunt TBI are at increased risk of respiratory and venous thromboembolic complications. However, underweight patients appear to be at highest risk after severe blunt TBI, with significantly increased risks of morbidity and mortality.

Underweight rather than adiposity is an important predictor of death in rural Chinese adults: a cohort study

BACKGROUND

To assess the associations of body mass index (BMI) with all-cause and cause-specific mortalities among rural Chinese.

METHODS

A prospective study of 28 895 individuals was conducted from 2006 to 2014 in rural Deqing, China. Height and weight were measured. The association of BMI with mortality was assessed by using Cox proportional hazards model and restricted cubic spline regression.

RESULTS

There were a total of 2062 deaths during an average follow-up of 7 years. As compared with those with BMI of 22.0-24.9 kg/m², an increased risk of all-cause mortality was found for both underweight men (BMI <18.5 kg/m²) (adjusted HR (aHR): 1.45, 95% CI: 1.18 to 1.79) and low normal weight men (BMI of 18.5-21.9 kg/m²) (aHR: 1.20, 95% CI: 1.03 to 1.38). A J-shaped association was observed between BMI and all-cause mortality in men. Underweight also had an increased risk of cardiovascular disease and cancer mortalities in men. The association of underweight with all-cause mortality was more pronounced in ever smokers and older men (60+ years). The results remained after excluding participants who were followed up less than 1 year.

CONCLUSION

The present study suggests that underweight is an important predictor of mortality, especially for elderly men in the rural community of China.

The abdominal waist circumference and 4-year outcomes following peripheral bypass grafting

BACKGROUND

Current literature evaluating the relationship between obesity, utilizing measures other than the Body Mass Index (BMI), and postoperative outcomes following vascular surgery are sparse. This study aimed to investigate any association between abdominal waist circumference (AWC) and waist-hip ratio (WHR) in relation to postoperative morbidity and mortality following peripheral artery bypass graft (PABG) surgery.

METHODS

AWC and hip circumference (HC) were measured from pre-intervention magnetic resonance (MR) and computed tomography (CT) scans of patients undergoing elective and nonelective PABG. The AWC and WHR were assessed in relation to: the need for higher level care (i.e. level 2/3), the duration of higher level care, postoperative limb ischemia, postoperative hospital stay, graft patency on discharge and 30 day readmission, using logistic and linear regression analysis. Mortality was assessed using cox-regression analysis with calculation of hazard ratios at 30 days and 4 years.

RESULTS

In total, 177 patient images performed between January 2014 to January 2017 were analyzed. There were no significant intra-observer and interobserver differences in measurements of AWC and HC. Pre-intervention AWC was predictive of the need for higher level care following non-elective PABG (adjusted OR 1.1 [95% CI: 1.0-1.1, P=0.026]). An inverse relationship between AWC and mortality at 4 years was also observed (adjusted HR=0.9, 95% CI: 0.9-1.0, P=0.028). However, pre-intervention WHR failed to predict mortality and morbidity.

CONCLUSIONS

AWC may potentially be a suitable risk stratification tool in patients undergoing non-elective PABG. The association of AWC with long-term mortality outcomes require further investigation so that suitable cut-off values may be determined.

Underweight patients are an often under looked “At risk” population after undergoing posterior cervical spine surgery

Background

Body Mass Index (BMI) is a weight-for-height metric that is used to quantify tissue mass and weight levels. Past studies have mainly focused on the association of high BMI on spine surgery outcomes and shown variable conclusions. Prior results may have varied due to insufficient power or inconsistent categorical separation of BMI groups (e.g. underweight, overweight, or obese). Additionally, few studies have considered outcomes of patients with low BMI. The aim of the current study was to analyze patients along the entirety of the BMI spectrum and to establish specific granular BMI categories for which patients become at risk for complication and mortality following posterior cervical spine surgery.

Methods

Patients undergoing elective posterior cervical spine surgery were abstracted from the 2005–2016 National Surgical Quality Improvement Program (NSQIP) databases. Patients were aggregated into pre-established WHO BMI categories and adverse outcomes were normalized to average risk of normal-weight subjects (BMI 18.5–24.9 kg/m²). Risk-adjusted multivariate regressions were performed controlling for patient demographics and overall health.

Results

A total of 16,806 patients met inclusion criteria. Odds for adverse events for underweight patients (BMI < 18.5 kg/m²) were the highest among any category of patients along the BMI spectrum. These patients experienced increased odds of any adverse event (Odds Ratio (OR) = 1.67, p = 0.008, major adverse events (OR=2.08, p = 0.001), post-operative infection (OR = 1.95, p = 0.002), and reoperation (OR = 1.84, p = 0.020). Interestingly, none of the overweight or obese categories were found to be correlated with increased risk of adverse event categories other than super-morbidly obese patients (BMI>50.0 kg/m²) for post-operative infection (OR = 1.54, p = 0.041).

Conclusions

The current study found underweight patients to have the highest risk of adverse events after posterior cervical spine surgery. Increased pre-surgical planning and resource allocation for this population should be considered by physicians and healthcare systems, as is often already done for patients on the other end of the BMI spectrum.

Impact of preoperative nutritional scores on 1-year postoperative mortality in patients undergoing valvular heart surgery

OBJECTIVE

Malnutrition is a well-recognized risk factor for poor prognosis and mortality. We investigated whether preoperative malnutrition diagnosed with objective nutritional scores affects 1-year mortality in patients undergoing valvular heart surgery.

METHODS

In this retrospective cohort observational study, we evaluated the association among the Controlling Nutritional Status score, Prognostic Nutritional Index, and Geriatric Nutritional Risk Index with 1-year mortality in 1927 patients undergoing valvular heart surgery. We identified factors for mortality using multivariable Cox proportional hazard analysis and investigated the utility of nutritional scores for risk stratification.

RESULTS

Malnutrition, as identified by a high Controlling Nutritional Status score and low Prognostic Nutritional Index and Geriatric Nutritional Risk Index, was significantly associated with higher 1-year mortality. Kaplan-Meier survival curve showed that mortality significantly increased as the severity of malnutrition increased (log-rank test, P < .001). The predicted discrimination (C-index) was 0.79 with the Controlling Nutritional Status score, 0.77 with the Prognostic Nutritional Index, and 0.73 with the Geriatric Nutritional Risk Index. Each nutritional index (Controlling Nutritional Status; hazard ratio, 1.31, 95% confidence interval, 1.21-1.42, P < .001), the European System for Cardiac Operative Risk Evaluation II (hazard ratio, 1.07, 95% confidence interval, 1.04-1.09, P < .001), and chronic kidney disease (hazard ratio, 2.26, 95% confidence interval, 1.31-3.90, P = .003) were independent risk factors for mortality. The Controlling Nutritional Status score added to the European System for Cardiac Operative Risk Evaluation II significantly increased the predictive discrimination ability for mortality (C-index 0.82, 95% confidence interval, 0.78-0.87, P = .014) compared with the Controlling Nutritional Status or European System for Cardiac Operative Risk Evaluation II alone.

CONCLUSIONS

Preoperative malnutrition as assessed by objective nutritional scores was associated with 1-year mortality after valvular heart surgery. The Controlling Nutritional Status score had the highest predictive ability and, when added to the European System for Cardiac Operative Risk Evaluation II, provided more accurate risk stratification.

Blunt Traumatic Injury to the Superficial Femoral Artery in a Morbidly Obese Female: Case Report Using Endovascular Covered Stent Repair

Lower extremity vascular injuries following trauma are rare events that require prompt identification and management in order to prevent ischemia and limb loss. Endovascular approaches, rather than traditional open procedures, are increasingly used to treat a wide range of vascular disease. The use of endovascular repair for revascularization in the trauma setting is not routine but may provide an appealing alternative in select trauma patients and injuries. We present a case of successful endovascular repair with stent grafting of a superficial femoral artery intimal injury following a femur fracture in a 35-year-old morbidly obese female and review the current literature regarding the use of endovascular therapy in the trauma setting.

The effect of body mass index on outcomes following severe blunt chest trauma

INTRODUCTION

Obesity has been described as a significant risk factor for adverse outcomes in hospitalized patients. However, recent literature reports an "obesity paradox", suggesting that obesity may have a protective effect in a subset of surgical and critically ill patients. The present study assesses the effect of body mass index (BMI) on outcomes following severe isolated blunt chest trauma.

METHODS

This was a TQIP database study including patients with severe isolated blunt chest injury (chest AIS 3-5, extrathoracic AIS <3). Patients were excluded for age <20 or >89, death on arrival, facility transfer, or BMI <10 or >55. Patients were divided into five groups according to BMI: underweight (BMI <18.5), normal weight (18.5-24.9), overweight (25.0-29.9), obesity class 1 (30.0-34.9), obesity class 2 (35.0-39.9) and obesity class 3 (≥40.0). Logistic regression models were constructed to evaluate the effect of BMI on outcomes.

RESULTS

28,820 patients met criteria for inclusion in the analysis. After multivariable analysis, underweight patients as well as obesity class 2 and 3 patients had a significantly higher mortality (OR 1.86 [95% CI, 1.12-3.10], OR 1.48 [95% CI, 1.02-2.16], and OR 1.60 [95% CI, 1.03-2.50]), respectively. Underweight patients had significantly higher risk of overall complications as compared to normal weight patients (OR 1.58 [95% CI, 1.34-1.88]). Obesity class 2 and 3 were independently associated with increased respiratory complications (OR 1.60 [95% CI, 1.27-2.01] and OR 1.58 [95% CI, 1.20-2.09], respectively) and all classes of overweight and obese patients were associated with increased risk of VTE complications (OR 1.68 [95% CI, 1.23-2.27], OR 1.98 [95% CI, 1.42-2.77], OR 2.32 [95% CI, 1.55-3.48], OR 2.02 [95% CI, 1.23-3.33], respectively for overweight and obesity class 1, 2, 3).

CONCLUSIONS

The obesity paradox does not extend to severe blunt chest trauma. Underweight and obesity class 2 and 3 patients have worse mortality than normal weight patients. Obesity was independently associated with an increased risk of pulmonary and VTE complications.

Underweight patients are at just as much risk as super morbidly obese patients when undergoing anterior cervical spine surgery

BACKGROUND CONTEXT

Past studies have focused on the association of high body mass index (BMI) on spine surgery outcomes. These investigations have reported mixed conclusions, possible due to insufficient power, poor controlling of confounding variables, and inconsistent definitions of BMI categories (e.g. underweight, overweight, and obese). Few studies have considered outcomes of patients with low BMI.

PURPOSE

To analyze how anterior cervical spine surgery outcomes track with World Health Organization categories of BMI to better assess where along the BMI spectrum patients are at risk for adverse perioperative outcomes.

DESIGN/SETTING

Retrospective cohort study.

PATIENT SAMPLE

Patients undergoing elective anterior cervical spine surgery were abstracted from the 2005 to 2016 American College of Surgeons National Surgical Quality Improvement Program database.

OUTCOME MEASURES

Thirty-day adverse events, hospital readmissions, postoperative infections, and mortality.

METHODS

Patients undergoing anterior cervical spine procedures (anterior cervical discectomy and fusion, anterior cervical corpectomy, cervical arthroplasty) were identified in the 2005 to 2016 National Surgical Quality Improvement Program database. Patients were then aggregated into modified World Health Organization categories of BMI. Odds ratios of adverse outcomes, normalized to average risk of normal weight subjects (BMI 18.5-24.9 kg/m²), were calculated. Multivariate analyses were then performed on aggregated adverse outcome categories controlling for demographics (age, sex, functional status) and overall health as measured by the American Society of Anesthesiologists classification.

RESULTS

In total, 51,149 anterior cervical surgery patients met inclusion criteria. Multivariate analyses revealed the odds of any adverse event to be significantly elevated for underweight and super morbidly obese patients (Odds Ratios [OR] of 1.62 and 1.55, respectively). Additionally, underweight patients had elevated odds of serious adverse events (OR=1.74) and postoperative infections (OR=1.75) and super morbidly obese patients had elevated odds of minor adverse events (OR=1.72). Relative to normal BMI patients, there was no significant elevation for any adverse outcomes for any of the other overweight/obese categories, in fact some had reduced odds of various adverse outcomes.

CONCLUSIONS

Underweight and super morbidly obese patients have the greatest odds of adverse outcomes after anterior cervical spine surgery. The current study identifies underweight patients as an at-risk population that has previously not received significant focus. Physicians and healthcare systems should give additional consideration to this population, as they often already do for those at the other end of the BMI spectrum.

Open Abdominal Aortic Aneurysm Repair Is Associated with Higher Mortality Among Nonobese Patients and Higher Risk of Deep Wound Infections Among Obese Patients

BACKGROUND

Prevalence of obesity in the United States is increasing. The impact of obesity on outcomes after endovascular and open abdominal aortic aneurysm (AAA) repair is largely unknown. The purpose of this analysis was to compare the postoperative outcomes between obese and nonobese patients after these operations.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from years 2013-2015 was analyzed. Preoperative, intraoperative, and postoperative variables were compared between obese and nonobese patient groups. Then obese and nonobese patients were divided into 2 groups each, based on the type of surgery (endovascular repair of abdominal aortic aneurysms (EVAR) versus. open AAA repair), and the outcomes were compared. Then multivariant analysis was used to compare impact of operative modality on outcomes for obese and nonobese patients.

RESULTS

A total of 6,859 patients (men 80%, women 20%) underwent surgical procedures for AAA during this time period. Among these patients, 2,218 (32.3%) had body mass index (BMI) ≥30, and 4,641 (67.7%) had BMI <30. Obese patients were less likely to be > 80 years old, women, nonwhites, and smokers. Obese patients had lower mortality and higher risk of deep wound infections after surgery (P < 0.05). Among the obese patients, 83.1% underwent EVAR and 16.9% underwent open AAA repair; patients undergoing EVAR had shorter operative times, shorter length of hospital stays, and mortality (P < 0.05). Among nonobese patients, 81% underwent EVAR and 19% underwent open AAA repair. Patients undergoing EVAR had shorter duration of operation, length of hospital stay, and mortality (P < 0.05). Overall, mortality was the highest among nonobese patients undergoing open AAA repair (odds ratio (OR) 0.66, confidence interval (CI) 0.44-0.99, P < 0.05). Incidence of deep wound infections was the highest among obese patients undergoing open AAA repair (OR 4.3, CI: 1.2-14.6, P < 0.05).

CONCLUSIONS

Nonobese patients have high mortality after open AAA repair, and obese patients have higher incidence of deep wound infections after open AAA repair. For patients deemed appropriate anatomic candidates, EVAR should be preferred for nonobese patients to improve mortality and for obese patients to reduce the incidence of deep wound infections.