Derivation and Validation of Risk Score Including Nutritional Status Among Patients With Chronic Limb-threatening Ischemia: Insight From I-PAD NAGANO Registry

PURPOSE

Geriatric nutritional related index (GNRI) is a simple and well-established screening method of nutritional status. We aimed to develop and validate a scoring system including GNRI to predict long-term outcomes in patients with chronic limb-threatening ischemia (CLTI) undergoing endovascular treatment (EVT).

MATERIALS AND METHODS

Patients undergoing EVT for symptomatic LEAD from August 2015 to August 2016 were enrolled into the I-PAD NAGANO registry, a prospective, multicenter, observational registry. We identified predictors of amputation-free survival (AFS) at 5 years using Cox proportional hazards regression and developed a risk scoring system. The predictive performance of the risk score was assessed.

RESULTS

A total of 126 patients with CLTI were analyzed. Cox multivariate analysis revealed GNRI score <92 points, ≥72 years of age, hemodialysis, heart failure, and anemia to be significant predictors. We developed a 5-item risk score (I-PAD CLTI score) assigning points to each factor based on the magnitude of association with AFS at 5 years. The I-PAD CLTI score showed a c-index of 0.80 for 5-year AFS. Patients with high score (≥7 points, n=50) had an increased risk of AFS at 5 years compared with those with low score (<7 points, n=68) (26.5% vs 72.1%, p<0.001).

CONCLUSION

A simple 5-item risk score including nutritional status showed reasonable discriminative and prognostic ability for long-term AFS among patients with CLTI.

CLINICAL IMPACT

The I-PAD CLTI score, a simple five-item risk score including nutritional status determined by geriatric nutritional related index, showed reasonable discriminative and prognostic ability for long-term amputation free survival among patients with chronic limb-threatening ischemia. This risk score may be useful for clinicians to accurately predict patient's prognosis and thus identify high-risk patients who may derive the greater clinical benefit from more intensive risk modification. Further research is required to test the clinical utility of risk-score-based treatment approach to improve the prognosis of patients with chronic limb-threatening ischemia.

Analysis of in-hospital deaths in patients with critical limb ischemia necessitating invasive treatments: based on a Japanese nationwide database

Critical limb ischemia (CLI) is associated with systemic cardiovascular and non-cardiovascular diseases. Treatments primarily targeting limb-related outcomes may not improve overall life prognosis. We aimed to describe in-hospital mortality and the underlying etiologies in Japanese patients with CLI. We analyzed the Diagnosis Procedure Combination (DPC) database from approximately 1200 Japanese acute-care hospitals between April 2018 and March 2020. The definition of patients with CLI was based on the diagnostic codes listed as the most resource-intensive diagnosis and information regarding invasive procedures (endovascular treatment, bypass, or amputation). The DPC database provides information on whether in-hospital death was caused by the most resource-intensive diagnosis. Among 15,228 distinct patients with CLI, we identified 18,970 records, including 5,378 amputations. In-hospital death occurred in 1238 (6.5%) patients. Among them, 811 (65.5%) were due to causes unrelated to CLI. In patients who underwent amputation (n = 5378), causes unrelated to CLI accounted for 70.0% of in-hospital deaths, whereas among patients who did not undergo amputation (n = 13,592), this proportion was 60.1%. When compared to patients who died due to causes related to CLI, the prevalence of male patients was higher (62.6% vs 52.7%, p = 0.001), and amputation was more frequently performed (58.0% vs 47.1%, p < 0.001) in those who died due to causes unrelated to CLI. The majority of in-hospital deaths among patients with CLI necessitating endovascular treatment, bypass, or amputation were attributable to factors unrelated to the primary condition of CLI. Managing systemic cardiovascular and non-cardiovascular diseases beyond the affected limb is crucial to improve the prognosis of these patients.

Editor's Choice - Prognostic Factors and Models to Predict Mortality Outcomes in Patients with Peripheral Arterial Disease: A Systematic Review

OBJECTIVE

Predicting adverse outcomes in patients with peripheral arterial disease (PAD) is a complex task owing to the heterogeneity in patient and disease characteristics. This systematic review aimed to identify prognostic factors and prognostic models to predict mortality outcomes in patients with PAD Fontaine stage I - III or Rutherford category 0 - 4.

DATA SOURCES

PubMed, Embase, and Cochrane Database of Systematic Reviews were searched to identify studies examining individual prognostic factors or studies aiming to develop or validate a prognostic model for mortality outcomes in patients with PAD.

REVIEW METHODS

Information on study design, patient population, prognostic factors, and prognostic model characteristics was extracted, and risk of bias was evaluated.

RESULTS

Sixty nine studies investigated prognostic factors for mortality outcomes in PAD. Over 80 single prognostic factors were identified, with age as a predictor of death in most of the studies. Other common factors included sex, diabetes, and smoking status. Six studies had low risk of bias in all domains, and the remainder had an unclear or high risk of bias in at least one domain. Eight studies developed or validated a prognostic model. All models included age in their primary model, but not sex. All studies had similar discrimination levels of > 70%. Five of the studies on prognostic models had an overall high risk of bias, whereas two studies had an overall unclear risk of bias.

CONCLUSION

This systematic review shows that a large number of prognostic studies have been published, with heterogeneity in patient populations, outcomes, and risk of bias. Factors such as sex, age, diabetes, hypertension, and smoking are significant in predicting mortality risk among patients with PAD Fontaine stage I - III or Rutherford category 0 - 4.

Clinical Implications of Low Body Mass Index on Endovascular Lower Extremity Revascularization

BACKGROUND

The epidemic of obesity and associated cardiovascular morbidity continues to grow, attracting public attention and healthcare resources. However, the impact of malnutrition and being underweight continues to be overshadowed by obesity, especially in patients with peripheral arterial disease (PAD). This study assesses the characteristics and outcomes of patients with low body mass index (BMI ≤ 18.5) compared to patients with nonobese BMI undergoing peripheral vascular interventions (PVI).

METHODS

A retrospective analysis of patients undergoing PVI due to PAD registered in the Vascular Quality Initiative database. Patients were categorized into underweight (BMI ≤ 18.5) and nonobese BMI (BMI = 18.5-30). Patients in both groups were matched 3:1 for baseline demographic characteristics, comorbidities, medications, and indications. Kaplan-Meier analysis was done for long-term outcomes.

RESULTS

A total of 337,926 patients underwent PVI, of whom 12,935 (4%) were underweight, 215,728 (64%) were nonobese, and 109,263 (32%) were obese. Underweight patients were more likely to be older, female, smokers, with chronic obstructive pulmonary disorder, and more likely to present with chronic limb-threatening ischemia than nonobese patients. After propensity matching, there were 18,047 nonobese patients and 6,031 underweight patients. There were no significant differences in matched characteristics. Perioperatively, underweight patients were more likely to require a longer hospital length of stay. Underweight patients had statistically significantly higher 30-day mortality compared to patients with nonobese BMI (3% vs. 1.6%, P < 0.001) and a higher rate of thrombotic complications. As for long-term outcomes, underweight patients had a higher rate of reintervention (20% vs. 18%, P < 0.001) and major adverse limb events (27% vs. 22%, P < 0.001). The 4-year rate of amputation-free survival was significantly lower in underweight patients (70% vs. 82%, P < 0.001), and the 2-year freedom from major amputation (90% vs. 94%, P < 0.001) showed similar trends with worse outcomes in patients who were underweight.

CONCLUSIONS

Underweight patients with PAD are disproportionally more likely to be African American, females, and smokers and suffer worse outcomes after PVI than PAD patients with nonobese BMI. When possible, increased scrutiny and optimization of nutrition and other factors contributing to low BMI should be addressed prior to PVI.

Obesity and Peripheral Artery Disease: Current Evidence and Controversies

PURPOSE OF REVIEW

Obesity is a significant public health problem and a major risk factor for the development and progression of atherosclerosis and its cardiovascular manifestations. Lower extremity peripheral artery disease (PAD) affects 3%-10% of the Western population and, if left untreated, can lead to devastating outcomes with both an increased risk of morbidity and mortality. Interestingly, the association between obesity and PAD remains debatable. Whereas it is well known that PAD and obesity frequently overlap in the same patients, many studies have demonstrated a negative association between obesity and PAD and a protective effect of obesity on disease development and progression, a phenomenon described as the "obesity paradox." Possible mechanisms for this paradox may include genetic background, as assessed by mendelian randomization studies, adipose tissue dysfunction, and body fat distribution rather than adiposity, while other factors, such as sex, ethnicity, sarcopenia in the elderly population, or aggressive treatment of co-existing metabolic conditions in individuals with obesity compared to those with normal weight, could have some impact as well.

RECENT RINDINGS

Few reviews and meta-analyses examining systematically the relationship between obesity and PAD exist. The impact of PAD development due to the presence of obesity remains largely controversial. However, the most current evidence, backed by a recent meta-analysis, suggests a potential protective role of a higher body mass index on PAD-related complications and mortality. In this review, we discuss the association between obesity and PAD development, progression, and management, and the potential pathophysiologic mechanisms linking the two diseases.

Mortality risk in patients with underweight or obesity with peripheral artery disease: a meta-analysis including 5,735,578 individuals

OBJECTIVES

The "obesity paradox" - in which patients with obesity exhibit superior survival than normal-weight counterparts - has been reported for several diseases. However, obesity is a well-known risk factor for cardiovascular disease, and whether the obesity paradox is present in peripheral artery disease (PAD) is unknown.

METHODS

A comprehensive search for studies that reported mortality in patients with PAD grouped by BMI identified 12 studies. We compared the survival of underweight patients with those who were not underweight, and patients with obesity against those without. Underweight was defined by a BMI value of <18.5 kg/m² in most studies and obesity by BMI ≥ 30 kg/m². Subgroup analyses were performed according to length of follow-up, presentation of PAD, and mode of revascularization. Meta-regression analyses were conducted, with covariates including age, sex, presence of coronary artery disease (CAD) and diabetes mellitus (DM).

RESULTS

The mortality risk of underweight patients with PAD was significantly higher compared to those who are not underweight (HR 1.72, 95% CI 1.38-2.14; I² = 84.2%). In contrast, the mortality risk of patients with obesity with PAD was significantly lower than those without (HR 0.78, 95% CI 0.62-0.97; I² = 89.8%). These findings remained consistent regardless of the presentation of PAD, revascularization, age, sex, or presence of CAD. The risk of death in the short-term of underweight patients (HR 1.50, 95% CI 0.47-4.72) and patients with obesity (HR 0.86, 95% CI 0.66-1.13) were not significantly different from their counterparts. The meta-regression showed that of the association between obesity and better survival was more pronounced in studies with a greater proportion of patients with concomitant CAD (regression coefficient -0.029, 95% CI -0.054 to -0.004).

CONCLUSIONS

In patients with PAD, mortality is higher among underweight patients and lower among patients with obesity. The mechanisms underlying the obesity paradox in patients with PAD remain to be elucidated, and further evidence is required to guide optimal weight control strategies in these patients.

A Dose Response Association Between Body Mass Index and Mortality in Patients with Peripheral Artery Disease: A Meta-analysis Including 5 729 272 Individuals

OBJECTIVE

Obesity is a significant risk factor for atherosclerotic cardiovascular disease; however, the "obesity paradox", in which obese patients enjoy superior survival, has been observed in various cardiovascular conditions. Whether this phenomenon exists for peripheral artery disease (PAD) remains uncertain. The goal of this study was to evaluate the relationship between body mass index (BMI) and mortality in patients with PAD.

METHODS

A comprehensive literature search identified seven eligible cohort studies that reported the association between BMI and all cause mortality in patients with PAD. A dose response meta-analysis was done for all cause mortality, short term (30 day or in hospital) mortality and long term mortality. The dose response association between BMI and mortality was also assessed in patients who received endovascular therapy (EVT).

RESULTS

The non-linear dose response analysis showed that higher BMI values were associated with a lower mortality risk from the range between 15 kg/m² to approximately 33 - 34 kg/m². The risk of mortality increased slightly thereafter. This relationship was consistent with that of long term mortality but was not apparent in short term mortality. A U shaped relationship was also observed between BMI and mortality in patients who received EVT with the lowest mortality observed at around 30 kg/m².

CONCLUSION

The obesity paradox was evident in the analysis of long term survival among patients with PAD, with the lowest mortality rates observed in obese patients. However, this association was not observed for short term or in hospital mortality.

Body composition and mortality in patients undergoing endovascular treatment for peripheral artery disease

An inverse correlation between body mass index and mortality in patients with peripheral artery disease (PAD) has been reported. However, little information is available regarding the impact of body composition on the clinical outcomes in patients with PAD. This study evaluated the relationships between the lean body mass index (LBMI), body fat % (BF%), and mortality and major amputation rate in patients with PAD. We evaluated 320 patients with PAD after endovascular treatment (EVT) enrolled from August 2015 to July 2016 and divided them into low and high LBMI and BF% groups based on their median values (17.47 kg/m² and 22.07%, respectively). We assessed 3-year mortality and major amputation for the following patient groups: Low LBMI/Low BF%, Low LBMI/High BF%, High LBMI/Low BF%, and High LBMI/High BF%. During the median 3.1-year follow-up period, 70 (21.9%) patients died and 9 (2.9%) patients experienced major amputation. The survival rate was lower in the Low LBMI than in the High LBMI group, and was not significantly different between the Low and High BF% groups. Survival rates were lowest in the Low LBMI/Low BF% group (57.5%) and highest in the High LBMI/High BF% group (94.4%). There were no significant differences in major amputation rate between the Low LBMI and High LBMI groups, and between the Low BF% and High BF% groups. The Low LBMI and Low BF% groups were associated with an increased risk of mortality after adjustment for age, sex, frailty and conventional risk factors [hazard ratio (HR): 4.02; 95% confidence interval (CI) 2.10–7.70; p < 0.001 and HR: 4.48; 95% CI 1.58–12.68, p = 0.005, respectively], for age, sex, hemodialysis, and prior cerebral cardiovascular disease (HR: 3.63; 95% CI 1.93–6.82; p < 0.001 and HR: 4.03; 95% CI 1.43–11.42, p = 0.009, respectively) and for age, sex, and laboratory date (HR: 3.97; 95% CI 1.88–8.37; p < 0.001 and HR: 3.31; 95% CI 1.15–9.53, p = 0.026, respectively). In conclusion, Low LBMI and Low BF% were associated with poor prognosis in patients undergoing EVT for PAD, and mortality was the lowest in the High LBMI/High BF% group compared with other body composition groups.

Sinusoidal changes in transcutaneous oxygen pressure, suggesting Cheyne-Stokes respiration, are frequent and of poor prognosis among patients with suspected critical limb ischemia

BACKGROUND AND AIMS

Transcutaneous oxygen pressure (TcpO₂) is used in patients with suspected critical limb ischemia (CLI). Sinusoidal changes (SC~) in TcpO₂ are found in patients with Cheyne-Stokes respiration (CSR). We aimed to determine the characteristics of TcpO₂ changes at rest in patients with suspected CLI, define the objective criteria for SC ~ TcpO₂ patterns (SC+), and estimate the prevalence of SC+ in our population and its impact on the outcome.

METHODS

We retrospectively analyzed 300 chest TcpO₂ recordings performed in a 16-month period. We determined the presence/absence of SC ~ TcpO₂ by visual analysis. We determined the acceptable error in the regularity of peaks of the cross-correlation with ROC curve analysis, among patients with typical SC ~ TcpO₂ and non-sinusoidal patterns. Then, we defined SC + as a minimum of five peaks, a standard deviation of TcpO₂ >1.25 mmHg, an error in regularity of peaks of the cross-correlation < 10%, and a cycle length between 30 and 100 s. In patients included until October 2019, we compared the outcome as a function of SC + or SC- with Cox models.

RESULTS

Mathematical detection of SC + found that 43 patients (14.3%) fulfilled all four defined criteria at the chest level, but only 23 did so at the limb level. In the follow-up of 207 patients, the presence of Sc ~ TcpO₂ at the chest significantly increased the risk of mortality: hazard ratio: 2.69 [95%CI: 1.37-5.30]; p < 0.005.

CONCLUSIONS

SC ~ TcpO₂ is frequent, and is associated with a poor outcome in patients with suspected CLI.

A systematic review and meta-analysis of gender differences in long-term mortality and cardiovascular events in peripheral artery disease

OBJECTIVE

Individual studies of peripheral artery disease (PAD) have indicated that gender discrepancies exist in the symptoms, functional status, and treatment usage. It remains uncertain whether these discrepancies result in different long-term outcomes. We examined the potential gender differences in mortality and major adverse cardiovascular events (MACE) in patients with symptomatic PAD.

METHODS

The PubMed and Embase databases were searched for studies from 2000 to January 2019. After a review of 13,582 citations, 14 articles were analyzed. The reported age-adjusted hazard ratios (HRs) for gender differences in mortality and MACE were included in the meta-analysis. The mortality outcomes were stratified according to the clinical presentation and study context.

RESULTS

Male gender was associated with a greater risk of all-cause mortality (HR, 1.13; 95% confidence interval [CI], 1.10-1.16; P < .001) and MACE (HR, 1.10; 95% CI, 1.06-1.14; P < .001). In a stratified analysis, male gender was associated with a higher mortality risk for patients presenting with either critical limb ischemia (HR, 1.08; 95% CI, 1.05-1.10; P < .001) or mixed clinical presentations (HR, 1.16; 95% CI, 1.11-1.21; P < .001) but not for those with intermittent claudication (HR, 1.13; 95% CI, 0.98-1.30; P = .09). Elevated mortality risk was evident after revascularization (HR, 1.11; 95% CI, 1.04-1.19; P = .003), hospitalization (HR, 1.15; 95% CI, 1.08-1.22; P < .001), and amputation (HR, 1.09; 95% CI, 1.08-1.10; P < .001), although not in outpatient clinics (HR, 1.13; 95% CI, 0.97-1.32; P = .13), in men compared with women.

CONCLUSIONS

Greater mortality and MACE rates in men with PAD occurred despite other accepted gender disparities. The mechanisms underlying these gender differences in the outcomes for PAD patients require further investigation.

Blood albumin as a prognostic factor among unselected medically treated inpatients

Aim: The aim of this study is to determine the prognostic value of blood albumin (BA) in an unselected population of inpatients. Materials & methods: We performed prospective analysis of the medical documentation of 7279 patients hospitalized between July 2014 and September 2017. Results: Individuals with BA ≥3.35 mg/dl had significantly lower risk of in-hospital death (odds ratio [OR]: 0.22; 95% CI: 0.19-0.27; p < 0.001) and 14-day readmission (OR: 0.64; 95% CI: 0.55-0.77; p < 0.0001). BA concentration was the strongest favorable factor predicting inpatient survival in a Cox hazard regression model (OR: 0.43; 95% CI: 0.36-0.50; p < 0.001), did not correlate with body mass index and actual-to-ideal bodyweight ratio and was strongly affected by numerous non-nutrient factors. Conclusion: BA concentration showed similar or better predictive and diagnostic power in relation to all-cause in-hospital mortality and 14-day readmission among inpatients than selected multifactorial scores.

Association Between Underweight Body Mass Index and In-Hospital Outcome in Patients Undergoing Endovascular Interventions for Peripheral Artery Disease: A Propensity Score Matching Analysis

PURPOSE

To investigate in-hospital outcomes after endovascular therapy (EVT) in patients with severe peripheral artery disease (PAD) who had a low body mass index (BMI, kg/m²) compared to those with normal BMI.

MATERIALS AND METHODS

Using weighted data from the National Inpatient Sample (NIS) database between 2002 and 2014 and ICD-9 codes, 2614 patients were identified who were aged ≥18 years and underwent EVT for PAD in the lower limb vessels. EVT was defined as angioplasty, atherectomy, and/or stenting. After excluding individuals with BMI >24, there were 807 (31%) normal-weight (BMI 19-24) patients and 1807 (69%) underweight (BMI <19) individuals. All patients in both groups were matched for baseline demographic and clinical characteristics and critical limb ischemia in a 1:1 propensity score matching analysis using the nearest neighbor method.

RESULTS

Propensity score matching produced 2 groups of 685 patients that differed only in the incidence of chronic lung disease, which was more frequent in low-BMI patients (p=0.04). Patients with low BMI had a higher incidence of in-hospital mortality (4.8% vs 1.2%, p<0.001), major adverse cardiovascular events (composite of death, myocardial infarction, or stroke) (7.9% vs 4.1%, p=0.003), open bypass surgery (9.1% vs 6.0%, p=0.03), and infection (14.6% vs 10.5%, p=0.02) compared with the normal-BMI group. There was no significant difference in the incidence of vascular complications (p=0.31), major bleeding (p=0.17), major amputation (p=0.35), or acute kidney injury (p=0.09) between the low- and normal-BMI groups.

CONCLUSION

Low-BMI patients with PAD have worse in-hospital survival and more adverse outcomes after EVT.

Peripheral artery disease in HIV-infected older adults on antiretroviral treatment in Thailand

OBJECTIVES

HIV infection has become a chronic disease requiring long-term treatment. Premature cardiovascular disease resulting from atherosclerosis in the HIV-infected population has been observed. We assessed the prevalence of peripheral artery disease (PAD), a common consequence of atherosclerosis, in HIV-infected patients aged ≥ 50 years receiving antiretroviral treatment (ART).

METHODS

This cross-sectional study was conducted in 12 community hospitals in Chiang Mai, Thailand. Inclusion criteria were as follows: (1) age ≥ 50 years, (2) positive HIV status, and (3) currently receiving ART. Age- and sex-matched hospital patients without documented HIV infection were enrolled as a comparison group. Clinical data were extracted from hospital records. Personal information and details of PAD-related symptoms were obtained through face-to-face interviews. The diagnosis of PAD was made using ankle-brachial index (ABI) measurement.

RESULTS

Seven hundred and twenty-four participants were enrolled in the study (362 HIV-infected patients and 362 patients in the comparison group). In the HIV-infected group, 43% were male; the mean (± standard deviation) age was 57.8 ± 5.6 years. The mean (± standard deviation) times from HIV diagnosis and ART initiation were 10.0 ± 4.3 and 8.6 ± 3.5 years, respectively. The prevalence of abnormal ABI (< 1.00) was significantly lower in the HIV-infected group than in the comparison group (20 versus 27%, respectively; P = 0.03), while that of PAD (ABI ≤ 0.90) was not significantly different between the two groups (5 and 7%, respectively). In the HIV-infected group, female sex and low body mass index were independently associated with abnormal ABI.

CONCLUSIONS

The prevalence of PAD when measured by ABI in HIV-infected older adults was relatively low. A follow-up study to determine the incidence of PAD and its persistence with time is warranted.