Impact of sarcopenia in trauma and surgical patient population: A literature review

Is Sarcopenia Associated with Worse Outcomes Following Ventral Hernia Repair? A Systematic Review and Meta-Analysis

Background: The concept of preoperative prehabilitation has garnered attention as a means to manage the comorbidities of patients undergoing ventral hernia repair (VHR). In this regard, some comorbidities have been studied as potential risk factors for postoperative complications following VHR, such as diabetes, immunosuppression, and smoking. However, evidence regarding the impact of sarcopenia, defined by reduced muscle mass and highly associated with frailty syndrome, remains a gap. We aimed to perform a systematic review and meta-analysis analyzing the impact of sarcopenia on VHR outcomes. Methods: Cochrane Central, Embase, PubMed, MEDLINE, and Web of Science were searched for studies analyzing the impact of sarcopenia on VHR from inception until April 2024. Outcomes assessed were recurrence, surgical site occurrences (SSO), surgical site infection (SSI), and hospital length of stay (LOS). Data analysis was done using RStudio 4.1.2 Software. Results: The initial search yielded 263 results, of which 172 were screened after the exclusion of the duplicates. The full-text review was done for eight studies, of which three were included after applying the eligibility criteria. Our sample comprised 275 patients, of which 79 (28,7%) presented with sarcopenia. All included studies used radiological muscle findings to define sarcopenia. Our analysis showed no differences in recurrence rates between patients with sarcopenia and controls (risk ratios [RR]: 1.24; 95% confidence interval [CI]: 0.79-1.94; P = .35). Furthermore, no differences were found in SSI (RR: 0.7; 95% CI: 0.39-1.25.; P = .23). Interestingly, a higher SSO rate was noted for patients without sarcopenia (95% CI: 0.35-0.96; P = .04). No differences were found in LOS (mean difference 4.7 hours; 95% CI: -0.67 to 10.1; P = .4). Conclusion: Our analysis showed no differences were found in recurrence, SSI, and LOS following VHR in patients with sarcopenia. Furthermore, there was a reduced SSO for patients with sarcopenia.

Healthcare professionals beliefs and priorities for the rehabilitation of patients after ankle fracture surgery: A qualitative study

OBJECTIVE

The study aims to understand healthcare professionals' (HCPs) beliefs and practices in the treatment and rehabilitation of patients after ankle fracture surgery, with the goal of informing new rehabilitation interventions based on these insights.

BACKGROUND

There is considerable variation in postoperative rehabilitation advice given to patients with ankle fractures, leading to inconsistent care. Prior studies have primarily focused on patients' experiences, making it crucial to explore HCPs' perspectives to identify areas for intervention.

METHODS

The study utilised semi-structured interviews with HCPs involved in the multicentre randomised controlled Weightbearing in Ankle Fractures (WAX) trial. Interviewees included physiotherapists, consultant trauma and orthopaedic surgeons, and trainee surgeons. Interviews were conducted between February 2020 and December 2021. Data were analysed using a mixed deductive and inductive approach, aligning with the Behavioural Change Wheel framework to translate findings into potential intervention strategies.

RESULTS

18 Interviews were conducted, revealing discrepancies between patient and HCP beliefs about recovery, particularly regarding weight-bearing and managing physical symptoms like swelling and numbness. HCPs expressed varying beliefs on the safety of early weight-bearing and recognised historical practice and medicolegal concerns influencing rehabilitation advice. Themes highlighted the need for clearer communication, standardised advice, and the impact of HCPs' remarks on patients' recovery confidence.

CONCLUSIONS

Findings underscore the mismatch between patient expectations and HCP guidance, emphasising the need for consensus on rehabilitation protocols. The study advocates for tailored rehabilitation pathways that address individual patient recovery trajectories, reduce dependency on HCPs, and encourage patient self-management.

Body composition parameters in initial CT imaging of mechanically ventilated trauma patients: Single-centre observational study

BACKGROUND

Body composition parameters provide relevant prognostic significance in critical care cohorts and cancer populations. Published results regarding polytrauma patients are inconclusive to date. The goal of this study was to analyse the role of body composition parameters in severely injured trauma patients.

METHODS

All consecutive patients requiring emergency tracheal intubation and mechanical ventilation before initial computed tomography (CT) at a level-1 trauma centre over a 12-year period (2008-2019) were reanalysed. The analysis included CT-derived body composition parameters based upon whole-body trauma CT as prognostic variables for 30-day mortality, intensive care unit length of stay (ICU LOS) and mechanical ventilation duration.

RESULTS

Four hundred seventy-two patients (75% male) with a median age of 49 years, median injury severity score of 26 and 30-day mortality rate of 22% (104 patients) met the inclusion criteria and were analysed. Regarding body composition parameters, 231 patients (49%) had visceral obesity, 75 patients had sarcopenia (16%) and 35 patients had sarcopenic obesity (7.4%). After adjustment for statistically significant univariable predictors age, body mass index, sarcopenic obesity, visceral obesity, American Society of Anesthesiologists classification ≥3, injury severity score and Glasgow Coma Scale ≤ 8 points, the Cox proportional hazard model identified sarcopenia as significant prognostic factor of 30-day mortality (hazard ratio 2.84; 95% confidence interval 1.38-5.85; P = 0.004), which was confirmed in Kaplan-Meier survival analysis (log-rank P = 0.006). In a subanalysis of 363 survivors, linear multivariable regression analysis revealed no significant associations of body composition parameters with ICU LOS and duration of mechanical ventilation.

CONCLUSIONS

In a multivariable analysis of mechanically ventilated trauma patients, CT-defined sarcopenia was significantly associated with 30-day mortality whereas no associations of body composition parameters with ICU LOS and duration of mechanical ventilation were observed.

Severe trauma leads to sustained muscle loss, induced frailty, and distinct temporal changes in myokine and chemokine profiles of older patients

INTRODUCTION

Sarcopenia is a known risk factor for adverse outcomes across multiple disease states, including severe trauma. Factors such as age, hyperinflammation, prolonged immobilization, and critical illness may not only exacerbate progression of this disease but may also contribute to the development of induced sarcopenia, or sarcopenia secondary to hospitalization. This study seeks to (1) determine the effects of severe traumatic injury on changes in skeletal muscle mass in older adults; (2) test whether changes in skeletal muscle mass are associated with clinical frailty, physical performance, and health-related quality of life; and (3) examine trauma-induced frailty and temporal changes in myokine and chemokine profiles.

METHODS

A prospective, longitudinal cohort study of 47 critically ill, older (≥45 years) adults presenting after severe blunt trauma was conducted. Repeated measures of computed tomography-based skeletal muscle index, frailty, and quality of life were obtained in addition to selected plasma biomarkers over 6 months.

RESULTS

Severe trauma was associated with significant losses in skeletal muscle mass and increased incidence of sarcopenia from 36% at baseline to 60% at 6 months. Severe trauma also was associated with a transient worsening of induced frailty and reduced quality of life irrespective of sarcopenia status, which returned to baseline by 6 months after injury. Admission biomarker levels were not associated with skeletal muscle index at the time points studied but demonstrated distinct temporal changes across our entire cohort.

CONCLUSIONS

Severe blunt trauma in older adults is associated with increased incidence of induced sarcopenia and reversible induced frailty. Despite muscle wasting, functional decline is transient, with a return to baseline by 6 months, suggesting a need for holistic definitions of sarcopenia and further investigation into long-term functional outcomes in this population.

Pectoralis Muscle Index as Predictor of Outcomes in Patients With Severe Blunt Chest Wall Injury

INTRODUCTION

Sarcopenia has been shown to portend worse outcomes in injured patients; however, little is known about the impact of thoracic muscle wasting on outcomes of patients with chest wall injury. We hypothesized that reduced pectoralis muscle mass is associated with poor outcomes in patients with severe blunt chest wall injury.

METHODS

All patients admitted to the intensive care unit between 2014 and 2019 with blunt chest wall injury requiring mechanical ventilation were retrospectively identified. Blunt chest wall injury was defined as the presence of one or more rib fractures as a result of blunt injury mechanism. Exclusion criteria included lack of admission computed tomography imaging, penetrating trauma, <18 y of age, and primary neurologic injury. Thoracic musculature was assessed by measuring pectoralis muscle cross-sectional area (cm2) that was obtained at the fourth thoracic vertebral level using Slice-O-Matic software. The area was then divided by the patient height in meters2 to calculate pectoralis muscle index (PMI) (cm2/m2). Patients were divided into two groups, 1) the lowest gender-specific quartile of PMI and 2) second-fourth gender-specific PMI quartiles for comparative analysis.

RESULTS

One hundred fifty-three patients met the inclusion criteria with a median (interquartile range) age 48 y (34-60), body mass index of 30.1 kg/m2 (24.9-34.6), and rib score of 3.0 (2.0-4.0). Seventy-five percent of patients (116/153) were male. Fourteen patients (8%) had prior history of chronic lung disease. Median (IQR) intensive care unit length-of-stay and duration of mechanical ventilation (MV) was 18.0 d (13.0-25.0) and 15.0 d (10.0-21.0), respectively. Seventy-three patients (48%) underwent tracheostomy and nine patients (6%) expired during hospitalization. On multivariate linear regression, reduced pectoralis muscle mass was associated with increased MV duration when adjusting for rib score and injury severity score (β 5.98, 95% confidence interval 1.28-10.68, P = 0.013).

CONCLUSIONS

Reduced pectoralis muscle mass is associated with increased duration of MV in patients with severe blunt chest wall injury. Knowledge of this can help guide future research and risk stratification of critically ill chest wall injury patients.

Sarcopenia measured by tomography as a predictor of morbidity and mortality in thoracic surgery, a retrospective cohort study

BACKGROUND

Sarcopenia has been identified as a risk factor for perioperative adverse events. Several studies have shown that tomographic assessment of muscle mass can be an appropriate indicator of sarcopenia associated with morbidity and mortality. The aim of the study was to determine the association between height-adjusted area of ​​the pectoral and erector spinae muscles (haPMA and haESA) and perioperative morbidity and mortality in thoracic surgery.

METHODS

Retrospective cohort study. Measurement of muscle areas was performed by tomography. The outcomes were 30-day mortality and postoperative morbidity. The discriminative capacity of the muscle areas was evaluated with an analysis of ROC curves and the Youden index was used to establish a cut-off point. The raw morbidity and mortality risk was determined and adjusted for potential confounders.

RESULTS

A total of 509 patients taken to thoracic surgery were included. The incidence of 30-day mortality was 7.3%. An association was found between muscle areas and 30-day mortality and pneumonia, with adequate discriminative power for mortality (AUC 0.68 for haPMA and 0.67 for haESA). An haPMA less than 10 and haESA less than 8.5 cm2/m2 were identified as a risk factor for 30-day mortality with an adjusted OR of 2.34 (95%CI 1.03-5.15) and 2.22 (95%CI 1.10-6.04) respectively.

CONCLUSIONS

Sarcopenia, defined as low muscle area in the pectoral and erector spinae muscles, is associated with increased morbidity and mortality in patients undergoing thoracic surgery.

Adverse postoperative outcomes in elderly patients with sarcopenia

PURPOSE

No study has compared 30-day and 90-day adverse postoperative outcomes between old-age patients with and those without sarcopenia.

PATIENTS AND METHODS

We categorize elderly patients receiving major surgery into two groups according to the presence or absence of preoperative sarcopenia that were matched at a 1:4 ratio through propensity score matching (PSM). We analyzed 30-day or 90-day adverse postoperative outcomes and mortality in patients with and without sarcopenia receiving major surgery.

RESULTS

Multivariate logistic regression analyses revealed that the patients with preoperative sarcopenia were at significantly higher risk of 30-day postoperative mortality (adjusted odds ratio [aOR]. = 1.25; 95% confidence interval [CI]. = 1.03-1.52) and 30-day major complications such as postoperative pneumonia (aOR = 1.15; 95% CI = 1.00-1.40), postoperative bleeding (aOR = 2.18; 95% CI = 1.04-4.57), septicemia (aOR = 1.31; 95% CI = 1.03-1.66), and overall complications (aOR = 1.13; 95% CI = 1.00-1.46). In addition, surgical patients with sarcopenia were at significantly higher risk of 90-day postoperative mortality (aOR = 1.50; 95% CI = 1.29-1.74) and 90-day major complications such as pneumonia (aOR = 1.27; 95% CI = 1.10-1.47), postoperative bleeding (aOR = 1.90; 95% CI = 1.04-3.48), septicemia (aOR = 1.52; 95% CI = 1.28-1.82), and overall complications (aOR = 1.24; 95% CI = 1.08-1.42).

CONCLUSIONS

Sarcopenia is an independent risk factor for 30-day and 90-day adverse postoperative outcomes such as pneumonia, postoperative bleeding, and septicemia and increases 30-day and 90-day postoperative mortality among patients receiving major surgery. No study has compared 30-day and 90-day adverse postoperative outcomes between patients with and those without sarcopenia. We conducted a propensity score?matched (PSM) population-based cohort study to investigate the adverse postoperative outcomes and mortality in patients undergoing major elective surgery with preoperative sarcopenia versus those without preoperative sarcopenia. We demonstrated that sarcopenia is an independent risk factor for 30-day and 90-day adverse postoperative outcomes, such as postoperative pneumonia, bleeding, septicemia, and mortality after major surgery. Therefore, surgeons and anesthesiologists should attempt to correct preoperative sarcopenia, swallowing function, and respiratory muscle training before elective surgery to reduce postoperative complications that contribute to the decrease in surgical mortality.

Pathogenesis and comprehensive treatment strategies of sarcopenia in elderly patients with type 2 diabetes mellitus

Sarcopenia and diabetes are two age-related diseases that are common in the elderly population, and have a serious effect on their general health and quality of life. Sarcopenia refers to the progressive loss of muscle mass, strength and function, whereas diabetes is a chronic disease characterized by elevated blood sugar levels. The comorbidity of sarcopenia and diabetes is particularly concerning, as people with diabetes have a higher risk of developing sarcopenia due to the combination of insulin resistance, chronic inflammation and reduced physical activity. In contrast, sarcopenia destroyed blood sugar control and exacerbated the development of people with diabetes, leading to the occurrence of a variety of complications. Fortunately, there are a number of effective treatment strategies for sarcopenia in people with diabetes. Physical exercise and a balanced diet with enough protein and nutrients have been proved to enhance the muscular quality and strength of this population. Additionally, pharmacological therapies and lifestyle changes can optimize blood sugar control, which can prevent further muscle loss and improve overall health outcomes. This review aims to summarize the pathogenesis and comprehensive treatment strategies of sarcopenia in elderly patients with type 2 diabetes, which help healthcare professionals recognize their intimate connection and provide a new vision for the treatment of diabetes and its complications in this population. Through early identification and comprehensive treatment, it is possible to improve the muscle function and general quality of life of elderly with diabetes and sarcopenia.

Acute Changes in Body Muscle Mass and Fat Depletion in Hospitalized Young Trauma Patients: A Descriptive Retrospective Study

Background: Loss of muscle mass, and its strength, is associated with adverse outcomes in many medical and surgical conditions. Trauma patients may get malnourished during their hospital course due to many interrelated contributing factors. However, there is insufficient knowledge on the acute muscle and fat changes in young trauma patients in the early days post-admission. Objective: to explore the diagnosis, feeding status, and outcome of muscle mass loss among young abdominal polytrauma patients. Methods: It was a retrospective study including hospitalized abdominal trauma patients who underwent an abdominal computerized tomographic (CT) examination initially and a follow-up one week later. CT scan-based automatic and manual analysis of the muscles and fat of the abdominal region was calculated and compared. Also, we evaluated the feeding and nutritional values to explore the adequacy of the provided calories and proteins and the potential influence of enteral feeding on the CT-based parameters for muscle loss and fat depletion. Results: There were 138 eligible subjects with a mean age of 32.8 ± 13.5 years; of them, 92% were males. Operative interventions were performed on two-thirds of the patients, including abdominal surgery (43%), orthopedic surgeries (34%), and neurosurgical procedures (8.1%). On admission, 56% received oral feeding, and this rate slightly increased to 58.4% after the first week. Enteral feed was prescribed for the remaining, except for two patients. The percentage of change in the total psoas muscle area was significantly reduced after one week of admission in patients on enteral feed as compared to those in the oral feeding group (p = 0.001). There were no statistically significant differences in the percentages of changes in the CT scan findings except for the total psoas muscle area (p = 0.001) and para-spinal muscle area (p = 0.02), which reduced significantly in the those who underwent laparotomy as compared to those who did not need laparotomy. Trauma patients who underwent emergency abdominal surgery lost muscle and fat over time. Conclusions: Loss of muscle mass and body fat is not uncommon among young trauma patients. Patients who underwent laparotomy are more likely to be affected. Further larger studies are needed to assess the specific features in the younger trauma population and how far this can be influenced by the nutrition status and its impact on the clinical outcomes. It could be early or impending stages of sarcopenia linked to trauma patients, or just acute changes in the muscle and fat, that need further investigation and follow-up after hospital discharge.

The predictive value of computerized tomography-assessed sarcopenia for complicated appendicitis in geriatric patients

Objective

Geriatric patients have more complicated appendicitis, which leads to higher morbidity and mortality rates. Sarcopenia has been shown to have a negative impact on patients undergoing surgery. This study aims to reveal the predictive value of computerized tomography-assessed (CT-assessed) sarcopenia for complicated appendicitis in geriatric patients.

Methods

One-hundred fifty-four patients' with acute appendicitis age, gender, co-morbidities, appendicitis status, and body mass index (BMI) values were analyzed. The skeletal muscle index (SMI) and related measurements were evaluated.

Results

Fifty-two percent of the patients had complicated, and 48% had uncomplicated appendicitis. There was a statistically significant difference between uncomplicated and complicated cases regarding BMI, SMI, and muscle area values (P < 0.05). The cutoff point by Receiver Operating Characteristic Curve analysis was conducted for SMI and showed 71% sensitivity and 52% specificity (P = 0.042). Multivariate analysis has shown that comorbidities are significantly more associated with complicated appendicitis than sarcopenia.

Conclusion

Geriatric patients with lower BMI, decreased muscle area, and CT-detected sarcopenia have an increased risk of complicated appendicitis. Comorbidities are also important risk factors. Surgeons should be aware of factors leading to complicated appendicitis, which may cause higher morbidity and mortality rates in elderly patients.

Sarcopenia and Related Functional Outcomes Following Hip Surgery Among Egyptian Geriatric Patients With Hip Fracture

Background Sarcopenia is highly prevalent among elderly patients with hip fracture. Studies reported a significant association between sarcopenia and clinical outcomes in patients with hip fractures. The current study aimed to determine the prevalence of sarcopenia among elderly patients with hip fracture and its effect on short-term functional outcomes, highlighting predictors of postoperative functional decline.  Methods This is a cross-sectional study followed by a prospective cohort. Elderly patients (60 years and above) with hip fractures were recruited from the orthopedic department. Patients were followed by the ortho-geriatric team in the perioperative period and for three postoperative months. Patients were subjected to comprehensive geriatric assessment including a full history and physical examination. In the preoperative state and after three months of follow-up the following were assessed: functional independence using the Barthel index (BI); nutritional state using a checklist named DETERMINE Your Nutritional Health; sarcopenia using the SARC-F questionnaire assessing strength, ambulation, rising from a chair, climbing stairs, and fall history. Perioperative risk assessment and post-discharge care were obtained through medical records and by questioning patients or families. Preoperative sarcopenia was confirmed using the Ishii equation which is an equation that includes (age, calf circumference, and hand grip strength). Results Preoperative sarcopenia screening showed that 29.3% of patients suffered sarcopenia by SARC-F questionnaire and 28.6% by Ishii equation score. At the end of the follow-up, 57.9% of patients suffered sarcopenia by SARC-F questionnaire. There was a marked post-fracture decline in independence level; 52.1% had slight dependence in function, 27.1% had moderate dependence in function, and 20.7% had total dependence in function. Conclusion This study gives us the chance for a greater understanding of the negative effects of sarcopenia on the outcomes following hip fracture surgery in the geriatric population. It shows a prevalence of sarcopenia among the elderly with hip fractures at 29.3%. The elderly experience a marked post-fracture decline in their level of independence concerning basic activities of daily living. Those with older age, higher comorbidities, cognitive impairment, and functional dependence with poor nutritional state are more vulnerable to functional decline. Other perioperative risks include delayed surgery, surgery type, postoperative complications, longer hospital stays, lack of planned rehabilitative and nutritional plans, and postoperative depression. Early detection of sarcopenia helps establish early interventional plans to reverse such poor outcomes.

The more you have, the more you lose: Muscle mass changes in trauma patients with prolonged hospitalizations

INTRODUCTION

Sarcopenia is a clinically relevant loss of muscle mass with implications of increased morbidity and mortality in adult trauma populations.  Our study aimed to evaluate loss of muscle mass change in adult trauma patients with prolonged hospital stays.

METHODS

Retrospective analysis using institutional trauma registry to identify all adult trauma patients with hospital length of stay >14 days admitted to our Level 1 center between 2010 and 2017. All CT images were reviewed, and cross-sectional area (cm²) of the left psoas muscle was measured at the level of the third lumbar vertebral body to determine total psoas area (TPA) and Total Psoas Index (TPI) normalized for patient stature.  Sarcopenia was defined as a TPI on admission below gender specific thresholds of 5.45(cm²/m²) in men and 3.85(cm²/m²) in women.  TPA, TPI, and rates of change in TPI were then evaluated and compared between sarcopenic and non-sarcopenic adult trauma patients.

RESULTS

There were 81 adult trauma patients who met inclusion criteria. The average change in TPA was -3.8 cm² and TPI was -1.3 cm². On admission, 23% (n = 19) of patients were sarcopenic while 77% (n = 62) were not. Non-sarcopenic patients had a significantly greater change in TPA (-4.9 vs. -0.31, p<0.0001), TPI (-1.7 vs. -0.13, p<0.0001), and rate of decrease in muscle mass (p = 0.0002). 37% of patients who were admitted with normal muscle mass developed sarcopenia during admission.  Older age was the only risk factor independently associated with developing sarcopenia (OR: 1.04, 95%CI 1.00-1.08, p = 0.045).

CONCLUSION

Over a third of patients with normal muscle mass at admission subsequently developed sarcopenia with older age as the primary risk factor. Patients with normal muscle mass at admission had greater decreases in TPA and TPI, and accelerated rates of muscle mass loss compared to sarcopenic patients.

The Impact of Body Mass Composition on Outcome in Multiple Traumatized Patients—Results from the Fourth Thoracic and Third Lumbar Vertebrae: A Single-Center Retrospective Observational Study

Background: Body mass composition (BC) was shown to correlate with outcome in patients after surgery and minor trauma. As BC is assessed using computed tomography (CT) and routinely applied in multiple trauma (MT), this study will help to analyze whether BC variables also correlate with outcome in trauma patients. Materials and Methods: Inclusion criteria were MT (Injury Severity Score (ISS) > 15) and whole-body CT (WBCT) scan on admission. Muscle and fat tissue were assessed at the level of the fourth thoracic vertebra (T4) and the third lumbar vertebra (L3) using Slice-O-matic software, version 5.0 (Tomovision, Montreal, QC, Canada). Univariate and multivariate regression models were used with regard to outcome parameters such as duration of ventilation, hospital stay, local (i.e., pneumonia, wound infection) and systemic (i.e., MODS, SIRS) complications, and mortality. Results: 297 patients were included. BC correlated with both the development and severity of complications. Skeletal muscle index (SMI) and subcutaneous adipose tissue index (SATI) at both T4 and L3 correlated positively with the occurrence of systemic infections. Local infections positively correlated with SMI at T4. Low muscle mass and high visceral adipose tissue (VAT) predicted the severity of systemic and local complications. Muscle tissue markers at both T4 and L3 predicted the severity of complications in roughly the same way. Moreover, higher muscle mass at the L3 level was significantly associated with higher overall survival, while SATI at the T4 level correlated positively with hospital stay, length of stay in the ICU, and duration of ventilation. Conclusions: A lower muscle mass and a high adipose tissue index are associated with a poor outcome in MT. For the first time, it was shown that BC at the fourth thoracic vertebra is associated with comparable results to those found at the third lumbar level.

Clinical evaluation of automated segmentation for body composition analysis on abdominal L3 CT slices in polytrauma patients

INTRODUCTION

Sarcopenia is a muscle disease that involves loss of muscle strength and physical function and is associated with adverse health effects. Even though sarcopenia has attracted increasing attention in the literature, many research findings have not yet been translated into clinical practice. In this article, we aim to validate a deep learning neural network for automated segmentation of L3 CT slices and aim to explore the potential for clinical utilization of such a tool for clinical practice.

MATERIALS AND METHODS

A deep learning neural network was trained on a multi-centre collection of 3413 abdominal cancer surgery subjects to automatically segment muscle, subcutaneous and visceral adipose tissue at the L3 lumbar vertebral level. 536 Polytrauma subjects were used as an independent test set to show generalizability. The Dice Similarity Coefficient was calculated to validate the geometric similarity. Quantitative agreement was quantified using Bland-Altman's Limits of Agreement interval and Lin's Concordance Correlation Coefficient. To determine the potential clinical usability, randomly selected segmentation images were presented to a panel of experienced clinicians to rate on a Likert scale.

RESULTS

Deep learning results gave excellent agreement versus a human expert operator for all of the body composition indices, with Concordance Correlation Coefficient for skeletal muscle index of 0.92, Skeletal muscle radiation attenuation 0.94, Visceral Adipose Tissue index 0.99 and Subcutaneous Adipose Tissue Index 0.99. Triple-blinded visual assessment of segmentation by clinicians correlated only to the Dice coefficient, but had no association to quantitative body composition metrics which were accurate irrespective of clinicians' visual rating.

CONCLUSION

A deep learning method for automatic segmentation of truncal muscle, visceral and subcutaneous adipose tissue on individual L3 CT slices has been independently validated against expert human-generated results for an enlarged polytrauma registry dataset. Time efficiency, consistency and high accuracy relative to human experts suggest that quantitative body composition analysis with deep learning should is a promising tool for clinical application in a hospital setting.

Impact of sarcopenia in bladder preservation therapy for muscle-invasive bladder cancer patients: a narrative review

BACKGROUND AND OBJECTIVE

Muscle-invasive bladder cancer (MIBC) is a biologically aggressive disease and its prognosis is poor. Radical cystectomy (RC) with urinary diversion and lymph node dissection is the gold standard treatment for MIBC patients. Accumulating evidence indicates that sarcopenia, the degenerative and systemic loss of skeletal muscle mass, is a significant predictor of higher rates of mortality and perioperative complications following RC. Recently, bladder preservation therapy has been offered as an alternative in appropriately selected MIBC patients who desire to preserve their bladders and those unfit or unwilling for RC. Here, we performed a narrative review on the impact of sarcopenia on oncological outcomes and complication rates in MIBC patients treated with bladder preservation therapy.

METHODS

A literature review was performed using the PubMed and Scopus databases.

KEY CONTENT AND FINDINGS

We identified two studies reported the impact of sarcopenia on responses to trimodal therapy and survival outcomes in MIBC patients. Consolidative partial cystectomy was performed in patients who achieved clinical complete response (CR) to trimodal therapy in one of the two studies. In both studies, CR rates to trimodal therapy are comparable between sarcopenic and non-sarcopenic patients. Sarcopenia was not significantly associated with shorter survival after completing bladder preservation therapy in either study. For complication rates of bladder preservation therapy, one study showed equivalent complication rates of consolidative partial cystectomy between sarcopenic and non-sarcopenic patients. In addition, in another small series of trimodal therapy, sarcopenic patients showed a higher rate of complications of trimodal therapy compared with non-sarcopenic patients.

CONCLUSIONS

According to the result of our literature review, sarcopenia would not affect responses to trimodal therapy and prognosis in MIBC patients treated with bladder preservation therapy. Although the effect of sarcopenia on complication rates of bladder preservation therapy is inconclusive due to limited evidence, bladder preservation therapy could be a viable alternative option in carefully selected MIBC patients regardless of the presence of sarcopenia.

The Fragility Fracture Postoperative Mobilisation multicentre audit : the reality of weightbearing practices following operations for lower limb fragility fractures

AIMS

The purpose of this study was to determine the weightbearing practice of operatively managed fragility fractures in the setting of publically funded health services in the UK and Ireland.

METHODS

The Fragility Fracture Postoperative Mobilisation (FFPOM) multicentre audit included all patients aged 60 years and older undergoing surgery for a fragility fracture of the lower limb between 1 January 2019 and 30 June 2019, and 1 February 2021 and 14 March 2021. Fractures arising from high-energy transfer trauma, patients with multiple injuries, and those associated with metastatic deposits or infection were excluded. We analyzed this patient cohort to determine adherence to the British Orthopaedic Association Standard, "all surgery in the frail patient should be performed to allow full weight-bearing for activities required for daily living".

RESULTS

A total of 19,557 patients (mean age 82 years (SD 9), 16,241 having a hip fracture) were included. Overall, 16,614 patients (85.0%) were instructed to perform weightbearing where required for daily living immediately postoperatively (15,543 (95.7%) hip fracture and 1,071 (32.3%) non-hip fracture patients). The median length of stay was 12.2 days (interquartile range (IQR) 7.9 to 20.0) (12.6 days (IQR 8.2 to 20.4) for hip fracture and 10.3 days (IQR 5.5 to 18.7) for non-hip fracture patients).

CONCLUSION

Non-hip fracture patients experienced more postoperative weightbearing restrictions, although they had a shorter hospital stay. Patients sustaining fractures of the shaft and distal femur had a longer median length of stay than demographically similar patients who received hip fracture surgery. We have shown a significant disparity in weightbearing restrictions placed on patients with fragility fractures, despite the publication of a national guideline. Surgeons intentionally restrict postoperative weightbearing in the majority of non-hip fractures, yet are content with unrestricted weightbearing following operations for hip fractures. Cite this article: Bone Joint J 2022;104-B(8):972-979.

Associations of sarcopenia with graft failure and mortality in patients undergoing living donor liver transplantation

Recent studies have reported that sarcopenia influences morbidity and mortality in surgical patients. However, few studies have investigated the associations of sarcopenia with short-term and long-term graft failure in recipients after living donor liver transplantation (LDLT). In this study, we investigated the associations between sarcopenia and graft failure/mortality in patients undergoing LDLT. We retrospectively examined 2816 recipients who underwent LDLT between January 2008 and January 2018. Cox regression analysis was performed to evaluate the associations between sarcopenia and graft failure/mortality in recipients at 60 days, 180 days, and 1 year and overall. Sarcopenia in the recipient was significantly associated with 60-day graft failure (adjusted hazard ratio [HR], 1.98; 95% confidence interval [CI], 1.09-3.61; p = 0.03), 180-day graft failure (HR, 1.85; 95% CI, 1.19-2.88; p = 0.01), 1-year graft failure (HR, 1.45; 95% CI, 1.01-2.17; p = 0.05), and overall graft failure (HR, 1.42; 95% CI, 1.08-1.87; p = 0.01). In addition, recipient sarcopenia was associated with 180-day mortality (HR, 1.88; 95% CI, 1.17-3.01; p = 0.01), 1-year mortality (HR, 1.53; 95% CI, 1.01-2.29; p = 0.04), and overall mortality (HR, 1.43; 95% CI, 1.08-1.90; p = 0.01). Preoperative sarcopenia was associated with high rates of graft failure and mortality in LDLT recipients. Therefore, preoperative sarcopenia may be a strong predictor of the surgical prognosis in LDLT recipients.

Impact of Sarcopenia and Bone Mineral Density on Implant Failure after Dorsal Instrumentation in Patients with Osteoporotic Vertebral Fractures

Background and Objectives: Age-related loss of bone and muscle mass are signs of frailty and are associated with an increased risk of falls and consecutive vertebral fractures. Management often necessitates fusion surgery. We determined the impacts of sarcopenia and bone density on implant failures (IFs) and complications in patients with spondylodesis due to osteoporotic vertebral fractures (OVFs). Materials and Methods: Patients diagnosed with an OVF according to the osteoporotic fracture classification (OF) undergoing spinal instrumentation surgery between 2011 and 2020 were included in our study. The skeletal muscle area (SMA) was measured at the third lumbar vertebra (L3) level using axial CT images. SMA z-scores were calculated for the optimal height and body mass index (BMI) adjustment (zSMA_HT). The loss of muscle function was assessed via measurement of myosteatosis (skeletal muscle radiodensity, SMD) using axial CT scans. The bone mineral density (BMD) was determined at L3 in Hounsfield units (HU). Results: A total of 68 patients with OVFs underwent instrumentation in 244 segments (mean age 73.7 ± 7.9 years, 60.3% female). The median time of follow-up was 14.1 ± 15.5 months. Sarcopenia was detected in 28 patients (47.1%), myosteatosis in 45 patients (66.2%), and osteoporosis in 49 patients (72%). The presence of sarcopenia was independent of chronological age (p = 0.77) but correlated with BMI (p = 0.005). The zSMA_HT was significantly lower in patients suffering from an IF (p = 0.0092). Sarcopenia (OR 4.511, 95% CI 1.459–13.04, p = 0.0092) and osteoporosis (OR 9.50, 95% CI 1.497 to 104.7, p = 0.014) increased the likelihood of an IF. Using multivariate analysis revealed that the zSMA_HT (p = 0.0057) and BMD (p = 0.0041) were significantly related to IF occurrence. Conclusion: Herein, we established sarcopenic obesity as the main determinant for the occurrence of an IF after instrumentation for OVF. To a lesser degree, osteoporosis was associated with impaired implant longevity. Therefore, measuring the SMA and BMD using an axial CT of the lumbar spine might help to prevent an IF in spinal fusion surgery via early detection and treatment of sarcopenia and osteoporosis.

Application of a Social-Ecological Model to Study the Factors Associated With Sarcopenia

The social-ecological model (SEM) provides a framework for developing multidimensional preventive strategies at the intrapersonal, interpersonal, organizational, community, and policy levels. While sarcopenia forms due to multiple factors, the SEM has not yet been applied to the prevention of sarcopenia. We aimed to categorize the factors associated with sarcopenia in each level of the SEM.

The electronic databases were searched between 2010 and 2021 to collect factors associated with sarcopenia. Information from guidelines, reference lists, and expert consultation was further hand-searched. The factors mentioned in the reviewed studies were classified into the SEM.

In 17 studies, 42 factors associated with sarcopenia were identified; thereafter, 33 biological and individual factors were categorized at the intrapersonal level, isolation was categorized at the interpersonal level, a sedentary lifestyle was at the organizational level, community involvement and social capital were at the community level, as well as knowledge about the disease, disability, income, education, and residential area were categorized at the policy level. The categorization of factors associated with sarcopenia, based on the SEM level, may be useful in the development of preventive strategies; however, further research is required.

CT anthropometric analysis of the prognosis of traumatic brain injury: A retrospective study to compare between psoas muscle and abdominal skeletal muscle

BACKGROUND

Recent studies have suggested that skeletal muscle area (SMA) and psoas muscle area (PMA), markers for sarcopenia, are associated with the prognosis of many diseases. However, it remains unclear which of the two is a superior prognostic marker. Thus, the objective of this study was to analyse these markers in patients with traumatic brain injury (TBI).

METHODS

Patients with TBI [abbreviated injury scale (AIS) score of 4 or 5] were selected. Those with an AIS score of 4 or 5 for chest, abdomen, or extremity lesion were excluded. Clinical data, including Glasgow Outcome Scale (GOS), mortality, and anthropometric data, were collected. SMA and PMA were measured. Skeletal muscle index (SMI) and psoas muscle index (PMI) were calculated for each muscle area divided by height squared. The good prognosis group was defined as patients with a GOS score of 4 to 5. The poor prognosis group was defined as those with a GOS score of 1-3. Data of both groups were analysed for the overall prognosis. After excluding patients with a hospital stay of 1 or 2 days, the modified prognosis and mortality of patients were analysed.

RESULTS

A total of 212 patients were enrolled in the statistical analysis. Patients with good prognosis showed a larger PMA (17.4 cm² vs. 15.0 cm², P = 0.002) and PMI (6.1 cm^2/ m² vs. 5.3 cm^2/ m², P = 0.001). After modification, patients with good prognosis showed a larger PMA (17.4 cm² vs. 14.9 cm², P = 0.002) and PMI (6.1 cm^2/ m² vs. 5.3 cm^2/ m², P = 0.01). On binary logistic regression analysis, PMI was found to be a significant risk factor for the modified prognosis (Odds ratio (OR) (95% confidence interval (CI)): 0.763 (0.633 - 0.921), P = 0.005) and modified mortality (OR (95% CI): 0.740 (0.573 - 0.957), P = 0.022).

CONCLUSION

Less amount of psoas muscle (PM) was found to be a significant risk factor for the prognosis of patients with TBI. PM was a better prognostic marker than skeletal muscle (SM) in patients with TBI. Further studies are needed to increase our understanding of sarcopenia and TBI.

Predicting mortality in elderly trauma patients: a review of the current literature

PURPOSE OF REVIEW

Advances in medical care allow patients to live longer, translating into a larger geriatric patient population. Adverse outcomes increase with older age, regardless of injury severity. Age, comorbidities, and physiologic deterioration have been associated with the increased mortality seen in geriatric trauma patients. As such, outcome prediction models are critical to guide clinical decision making and goals of care discussions for this population. The purpose of this review was to evaluate the various outcome prediction models for geriatric trauma patients.

RECENT FINDINGS

There are several prediction models used for predicting mortality in elderly trauma patients. The Geriatric Trauma Outcome Score (GTOS) is a validated and accurate predictor of mortality in geriatric trauma patients and performs equally if not better to traditional scores such as the Trauma and Injury Severity Score. However, studies recommend medical comorbidities be included in outcome prediction models for geriatric patients to further improve performance.

SUMMARY

The ideal outcome prediction model for geriatric trauma patients has not been identified. The GTOS demonstrates accurate predictive ability in elderly trauma patients. The addition of medical comorbidities as a variable in outcome prediction tools may result in superior performance; however, additional research is warranted.

Prognostic impact of sarcopenia on immune-related adverse events in malignancies received immune checkpoint inhibitors: a systematic review and meta-analysis

BACKGROUND

Whether sarcopenia has an impact on immune-related adverse events (irAEs) in patients with malignant neoplasms receiving immune checkpoint inhibitors (ICIs) is not consistent. This study aimed to evaluate the impact of sarcopenia on all grades of irAEs.

METHODS

PubMed, Embase, and Cochrane Library databases were systematically searched for related studies up to May 2021. Eligible studies were included according to the PICOS criteria. The risk of bias of the included studies was assessed according to the Newcastle-Ottawa Scale (NOS). The odds ratio (OR), corresponding to the 95% confidence interval (CI) of all grades of irAEs, was collected and analyzed, and a further subgroup analysis of serious adverse events was conducted. All analyses were conducted using the RevMan 5.4 software downloaded from the Cochrane website. The heterogeneity and sensitivity of the study were assessed.

RESULTS

Of the 135 references identified, only 8 studies were analyzed, including 519 patients comprising 250 with sarcopenia and 269 without sarcopenia. No obvious bias was observed in the included studies. An increased incidence of irAEs was not observed in patients with sarcopenia at pre-immunotherapy compared to those without sarcopenia. The OR and corresponding 95% CI were 0.97 and 0.62-1.53, respectively (P=0.90), with low heterogeneity (P=0.17, I² =32%). Further, severe adverse events were analyzed in three studies, and the results showed that sarcopenia was not related to irAEs (P=0.97).

CONCLUSIONS

Malignancies with sarcopenia at pre-immunotherapy may not increase the incidence of irAEs, and sarcopenia may not be a predictive factor for irAEs.

Psoas Muscle Mass can Predict Postsurgical Outcomes in Patients Who Undergo Radical Cystectomy and Urinary Diversion Reconstruction

OBJECTIVE

To morphometrically measure to muscle mass which may reflect physical components of frailty. Hence, we evaluated the association between L4 total psoas area (TPA) and operative outcome after radical cystectomy (RC) for bladder cancer.

METHODS

In a retrospective single-center study, bladder cancer patients who underwent RC and urinary diversion between 2007 and 2012 were enrolled. TPA was evaluated in the cross-sectional imaging. The psoas muscles were normalized with the height. Male patients with a psoas mass index ≤7.4 cm²/m² and female patients with a psoas mass index ≤5.2 cm²/m² were classified as sarcopenic. Outcome measures were 30- and 90-day readmission and complications, and survival. Multivariable logistic and Cox proportional-hazards regression models were used to determine relevant predictors.

RESULTS

The median age of the 441 participants and follow up time was 68 years (IQR 59-75) and 1.2 years (IQR 0.5-1.9), respectively. One hundred forty-three patients (32.4%) were sarcopenic. The 30-day readmission and the complication rates were 13.8% and 44.7%, respectively. The 90-day readmission and complication rates were 23.9% and 53.1%, respectively. The 1-year mortality rate was 11.6% (95%CI 8.7-15.4). Multivariable logistic regression analysis revealed an association between increased TPA and lower odds of 30-day complications after RC (OR 0.95, 95%CI 0.92-0.99, P = .02); similarly, an increase in TPA was of prognostic value, although not statistically significant in the multivariable model (P = .05) once adjusting for other patient factors.

CONCLUSION

Sarcopenia predicted early complications and showed an informative trend for overall survival after RC, and thus may inform models predicting postsurgical outcomes.

Mitochondrial Dynamics and Mitophagy in Skeletal Muscle Health and Aging

The maintenance of mitochondrial integrity is critical for muscle health. Mitochondria, indeed, play vital roles in a wide range of cellular processes, including energy supply, Ca²⁺ homeostasis, retrograde signaling, cell death, and many others. All mitochondria-containing cells, including skeletal muscle cells, dispose of several pathways to maintain mitochondrial health, including mitochondrial biogenesis, mitochondrial-derived vesicles, mitochondrial dynamics (fusion and fission process shaping mitochondrial morphology), and mitophagy—the process in charge of the removal of mitochondria though autophagy. The loss of skeletal muscle mass (atrophy) is a major health problem worldwide, especially in older people. Currently, there is no treatment to counteract the progressive decline in skeletal muscle mass and strength that occurs with aging, a process termed sarcopenia. There is increasing data, including our own, suggesting that accumulation of dysfunctional mitochondria contributes to the development of sarcopenia. Impairments in mitochondrial dynamics and mitophagy were recently proposed to contribute to sarcopenia. This review summarizes the current state of knowledge on the role played by mitochondrial dynamics and mitophagy in skeletal muscle health and in the development of sarcopenia. We also highlight recent studies showing that enhancing mitophagy in skeletal muscle is a promising therapeutic target to prevent or even treat skeletal muscle dysfunction in the elderly.

Interventions to prevent and treat sarcopenia in a surgical population: a systematic review and meta-analysis

BACKGROUND

The aim of this systematic review was to summarize the results of trials evaluating interventions for the reduction of sarcopenia in patients undergoing surgery.

METHODS

Searches were conducted using the Cochrane Central Register of Controlled Trials, MEDLINE and Embase. RCTs evaluating exercise, dietary or pharmacological interventions to address sarcopenia in the perioperative period were included. Treatment effect estimates were expressed as standardized mean differences (MDs) with confidence intervals, and heterogeneity was expressed as I2 values.

RESULTS

Seventy trials including 3402 participants were selected for the data synthesis. Exercise interventions significantly increased muscle mass (MD 0.62, 95 per cent c.i. 0.34 to 0.90; P < 0.001), muscle strength (MD 0.55, 0.39 to 0.71; P < 0.001), measures of gait speed (MD 0.42, 0.05 to 0.79; P = 0.03), and reduced time for completion of set exercises (MD -0.76, -1.12 to -0.40; P < 0.001) compared with controls. Subgroup analysis showed that interventions in the early postoperative period were more likely to have a positive effect on muscle mass (MD 0.71, 0.35 to 1.07; P < 0.001) and timed tests (MD -0.70, -1.10 to -0.30; P = 0.005) than preoperative interventions. Treatment effects on muscle mass (MD 0.09, -0.31 to 0.49; P = 0.66) and strength (MD 0.46, -0.01 to 0.92; P = 0.05) were attenuated by the presence of cancer. Results of analyses restricted to nine trials at low risk of allocation concealment bias and fourteen trials at low risk of attrition bias were comparable to those of the primary analysis. Risk-of-bias assessment showed that most trials were at high risk of incomplete outcome and attrition bias, thus reducing the estimate of certainty of the evidence according to the GRADE assessment tool.

CONCLUSION

Exercise interventions appear beneficial in reducing the impact of sarcopenia. Because of the high risk of bias and low certainty of the current evidence, large RCTs using standardized measures of muscle mass should be undertaken.

A Novel Technique for Radiographic Diagnosis of Sarcopenia that Accurately Predicts Postoperative Complications in Lower Extremity Free Flap Patients

INTRODUCTION

 Sarcopenia is linked to poor outcomes throughout the surgical literature and can be assessed on preoperative imaging to potentially aid in risk stratification. This study examined the effects of sarcopenia on surgical morbidity following lower extremity (LE) reconstruction, and also compared two methods of assessment, one of which is novel ("ellipse method").

METHODS

 A retrospective cohort study of 50 patients receiving free flap-based reconstruction of the LE was performed. Bilateral psoas density and area were quantified at L4 through tracing ("traditional method") and encircling ("ellipse method") to calculate Hounsfield unit average calculation (HUAC). Logistic regression and receiving operator curve analysis for the primary outcome of any postoperative complication was used to determine HUAC cutoffs (≤ 20.7 vs. ≤ 20.6) for sarcopenia. Risk of complications associated with sarcopenia was evaluated using Fisher's exact tests.

RESULTS

 Twelve patients (24%) met criteria for sarcopenia via the traditional method and 16 (32%) via the ellipse method. By both methods, sarcopenic patients were older and more often female and diabetic. These patients also had higher American Society of Anesthesiologists scores and lower serum prealbumin levels. The ellipse method was found to be more accurate, sensitive, and specific than the traditional method in predicting postoperative morbidity (p = 0.009). Via the ellipse method, sarcopenic patients were at higher risk for any complication (p = 0.002) and were at a higher risk for a deep vein thrombus or pulmonary embolism via the traditional method (p = 0.047).

CONCLUSION

 Sarcopenia is associated with greater pre- and postoperative morbidity in LE reconstruction. The novel ellipse method is a simplified and accurate method of assessing sarcopenia that can be easily performed in the clinical setting.

Identification of Sarcopenia in Elderly Trauma Patients: The Value of Clinical Competency and Experience

INTRODUCTION

There is currently no standard definition of sarcopenia, which has often been associated with frailty. A commonly cited surrogate measure of sarcopenia is psoas muscle size. The purpose of this prospective study is to assess medical providers' capabilities to identify frail elderly trauma patients and consequent impact on outcomes after intensive care unit admission.

METHODS

Trauma intensive care unit patients over the age of 50 were enrolled. A preadmission functional status questionnaire was completed on admission. Attendings, residents, and nurses, blinded to their patient's sarcopenic status, completed surveys regarding 6-month prognosis. Chart review included cross-sectional psoas area measurements on computerized tomography scan. Finally, patients received phone calls 3 and 6 months after admission to determine overall health and functional status.

RESULTS

Seventy-six participants had an average age of 70 years and a corrected psoas area of 383 ± 101 mm²/m². Injury Severity Score distribution (17.2 ± 8.9) was similar for both groups. Patients also had similar preinjury activities of daily living. Both groups had similar hospital courses. While sarcopenic patients were less likely to be predicted to survive to 6 months (60% vs. 76%, P = 0.017), their actual 6-month mortality was similar (22% vs. 21%, P = 0.915).

CONCLUSION

Despite similar objective measures of preadmission health and trauma injury severity, medical providers were able to recognize frail patients and predicted they would have worse outcomes. Interestingly, sarcopenic patients had similar outcomes to the control group. Additional studies are needed to further delineate factors influencing provider insight into functional reserves of elderly trauma patients.

Skeletal muscle fat quantification by dual-energy computed tomography in comparison with 3T MR imaging

Objectives

To quantify the proportion of fat within the skeletal muscle as a measure of muscle quality using dual-energy CT (DECT) and to validate this methodology with MRI.

Methods

Twenty-one patients with abdominal contrast-enhanced DECT scans (100 kV/Sn 150 kV) underwent abdominal 3-T MRI. The fat fraction (DECT-FF), determined by material decomposition, and HU values on virtual non-contrast-enhanced (VNC) DECT images were measured in 126 regions of interest (≥ 6 cm²) within the posterior paraspinal muscle. For validation, the MR-based fat fraction (MR-FF) was assessed by chemical shift relaxometry. Patients were categorized into groups of high or low skeletal muscle mean radiation attenuation (SMRA) and classified as either sarcopenic or non-sarcopenic, according to the skeletal muscle index (SMI) and cut-off values from non-contrast-enhanced single-energy CT. Spearman’s and intraclass correlation, Bland-Altman analysis, and mixed linear models were employed.

Results

The correlation was excellent between DECT-FF and MR-FF (r = 0.91), DECT VNC HU and MR-FF (r = - 0.90), and DECT-FF and DECT VNC HU (r = − 0.98). Intraclass correlation between DECT-FF and MR-FF was good (r = 0.83 [95% CI 0.71–0.90]), with a mean difference of - 0.15% (SD 3.32 [95% CI 6.35 to − 6.66]). Categorization using the SMRA yielded an eightfold difference in DECT VNC HU values between both groups (5 HU [95% CI 23–11], 42 HU [95% CI 33–56], p = 0.05). No significant relationship between DECT-FF and SMI-based classifications was observed.

Conclusions

Fat quantification within the skeletal muscle using DECT is both feasible and reliable. DECT muscle analysis offers a new approach to determine muscle quality, which is important for the diagnosis and therapeutic monitoring of sarcopenia, as a comorbidity associated with poor clinical outcome.

Key Points

• Dual-energy CT (DECT) material decomposition and virtual non-contrast-enhanced DECT HU values assess muscle fat reliably.

• Virtual non-contrast-enhanced dual-energy CT HU values allow to differentiate between high and low native skeletal muscle mean radiation attenuation in contrast-enhanced DECT scans.

• Measuring muscle fat by dual-energy computed tomography is a new approach for the determination of muscle quality, an important parameter for the diagnostic confirmation of sarcopenia as a comorbidity associated with poor clinical outcome.

Sarcopenia as a Prognostic Factor in Peripheral Arterial Disease: Descriptive Review

BACKGROUND

Determine the influence of sarcopenia on the prognosis of peripheral arterial disease (PAD).

METHODS

A systematic search of the PubMed and Cochrane Library databases was performed with the keywords and medical subject heading (MesH): "muscle, skeletal", "sarcopenia", "prognosis", "duration of stay", "death", "mortality", "patient readmission", "length of stay", "peripheral arterial disease", "intermittent claudication" and "critical limb ischemia". Papers published from January 2010 to October 2020 in English, French, Spanish and Portuguese were eligible for inclusion. The primary outcome was overall survival. Secondary outcomes included post-operative complications, amputation, length of hospital stay and hospital readmission.

RESULTS

Of 1071 papers, 8 articles and 1511 patients were included (68.96% male, mean age 71.83 years). Five papers found an inverse relationship between SM area and mortality. Matsubara (2015) found that the 5-year overall survival rates were lower for patients with sarcopenia (23.5% ± 0.18% vs 77.5% ± 0.09% P = 0.001). Matsubara (2016) registered 3-year cardiovascular event-free survival rates of 43.1% and 91.2% for patients with and without sarcopenia (P < 0.01). Juszczak (2018) found that survival was lower in patients with reduced total psoas area. Taniguchi (2019) found that 3-year overall survival rate was 60% for patients with sarcopenia and 87% for patients without sarcopenia (P < 0.05). Shimazoe (2019) concluded sarcopenia was a significant predictor of overall survival. Distinctly, Nyers (2017) concluded that higher ratio bilateral psoas area to L4 vertebral body was associated with an increased risk of death. Two other studies analyzed other characteristics of the SM (density and strength). McDermott (2012) and found that lower calf muscle density and strength were associated with an increase in mortality. Sugai (2019) concluded that patients with major cardiovascular and limb events had a lower SM density.

CONCLUSIONS

Lower SM area and mass seem to be associated with a higher mortality in PAD patients.