Low skeletal muscle mass and postoperative morbidity in surgical oncology: a systematic review and meta-analysis

Bioelectrical Impedance Analysis and Mid-Upper Arm Muscle Circumference Can Be Used to Detect Low Muscle Mass in Clinical Practice

Identification of low muscle mass becomes increasingly relevant due to its prognostic value in cancer patients. In clinical practice, mid-upper arm muscle circumference (MAMC) and bioelectrical impedance analysis (BIA) are often used to assess muscle mass. For muscle-mass assessment, computed tomography (CT) is considered as reference standard. We investigated concordance between CT, BIA, and MAMC, diagnostic accuracy of MAMC, and BIA to detect low muscle mass and their relation with the clinical outcome malnutrition provided with the Patient-Generated Subjective Global Assessment Short Form (PG-SGA SF). This cross-sectional study included adult patients with advanced esophageal and gastrointestinal cancer. BIA, MAMC, and PG-SGA-SF were performed. Routine CT-scans were used to quantify psoas muscle index (PMI) and skeletal muscle area. Good concordance was found between CT_PMI and both BIA_{FFMI (fat free mass index)} (ICC 0.73), and BIA_{ASMI (appendicular skeletal muscle index)} (ICC 0.69) but not with MAMC (ICC 0.37). BIA_FFMI (94%), BIA_ASMI (86%), and MAMC (86%) showed high specificity but low sensitivity. PG-SGA-SF modestly correlated with all muscle-mass measures (ranging from -0.17 to -0.43). Of all patients with low muscle mass, 62% were also classified with a PG-SGA-SF score of ≥4 points. Although CT remains the first choice, since both BIA and MAMC are easy to perform by dieticians, they have the potential to be used to detect low muscle mass in clinical practice.

Low-dose MDCT: evaluation of the impact of systematic tube current reduction and sparse sampling on quantitative paraspinal muscle assessment

Background

Wasting disease entities like cachexia or sarcopenia are associated with a decreasing muscle mass and changing muscle composition. For valid and reliable disease detection and monitoring diagnostic techniques offering quantitative musculature assessment are needed. Multi-detector computed tomography (MDCT) is a broadly available imaging modality allowing for muscle composition analysis. A major disadvantage of using MDCT for muscle composition assessment is the radiation exposure. In this study we evaluated the performance of different methods of radiation dose reduction for paravertebral muscle composition assessment.

Methods

MDCT scans of eighteen subjects (6 males, age: 71.5±15.9 years, and 12 females, age: 71.0±8.9 years) were retrospectively simulated as if they were acquired at 50%, 10%, 5%, and 3% of the original X-ray tube current or number of projections (i.e., sparse sampling). Images were reconstructed with a statistical iterative reconstruction (SIR) algorithm. Paraspinal muscles (psoas and erector spinae muscles) at the level of L4 were segmented in the original-dose images. Segmentations were superimposed on all low-dose scans and muscle density (MD) extracted.

Results

Sparse sampling derived mean MD showed no significant changes (P=0.57 and P=0.22) down to 5% of the original projections in the erector spinae and psoas muscles, respectively. All virtually reduced tube current series showed significantly different (P>0.05) mean MD in the psoas and erector spinae muscles as compared to the original dose except for the images of 5% of the original tube current in the erector spinae muscle.

Conclusions

Our findings demonstrated the possibility of considerable radiation dose reduction using MDCT scans for assessing the composition of the paravertebral musculature. The sparse sampling approach seems to be promising and a potentially superior technique for dose reduction as compared to tube current reduction.

Body Composition and Dose-limiting Toxicity in Colorectal Cancer Chemotherapy Treatment; a Systematic Review of the Literature. Could Muscle Mass be the New Body Surface Area in Chemotherapy Dosing?

Chemotherapy dosing is traditionally based on body surface area calculations; however, these calculations ignore separate tissue compartments, such as the lean body mass (LBM), which is considered a big pool of drug distribution. In our era, colorectal cancer patients undergo a plethora of computed tomography scans as part of their diagnosis, staging and monitoring, which could easily be used for body composition analysis and LBM calculation, allowing for personalised chemotherapy dosing. This systematic review aims to evaluate the effect of muscle mass on dose-limiting toxicity (DLT), among different chemotherapy regimens used in colorectal cancer patients. This review was carried out according to the PRISMA guidelines. MEDLINE and EMBASE databases were searched from 1946 to August 2019. The primary search terms were 'sarcopenia', 'myopenia', 'chemotherapy toxicity', 'chemotherapy dosing', 'dose limiting toxicity', 'colorectal cancer', 'primary colorectal cancer' and 'metastatic colorectal cancer'. Outcomes of interest were - DLT and chemotoxicity related to body composition, and chemotherapy dosing on LBM. In total, 363 studies were identified, with 10 studies fulfilling the selection criteria. Seven studies were retrospective and three were prospective. Most studies used the same body composition analysis software but the chemotherapy regimens used varied. Due to marked study heterogeneity, quantitative data synthesis was not possible. Two studies described a toxicity cut-off value for 5-fluorouracil and one for oxaliplatin based on LBM. The rest of the studies showed an association between different body composition metrics and DLTs. Prospective studies are required with a larger colorectal cancer cohort, longitudinal monitoring of body composition changes during treatment, similar body composition analysis techniques, agreed cut-off values and standardised chemotherapy regimens. Incorporation of body composition analysis in the clinical setting will allow early identification of sarcopenic patients, personalised dosing based on their LBM and early optimisation of these patients undergoing chemotherapy.

Effect of sarcopenia on survival and spinal cord deficit outcomes after thoracoabdominal aortic aneurysm repair in patients 60 years of age and older

OBJECTIVE

Sarcopenia (core muscle loss) has been used as a surrogate marker of frailty. We investigated whether sarcopenia would adversely affect survival after thoracoabdominal aortic aneurysm repair.

METHODS

We retrospectively reviewed prospectively collected data from patients aged 60 years or older who underwent thoracoabdominal aortic aneurysm repairs from 2006 to 2016. Imaging was reviewed by 2 radiologists blinded to clinical outcomes. The total psoas index was derived from total psoas muscle cross-sectional area (cm²) at the mid-L4 level, normalized for height (m²). Patients were divided by sex-specific total psoas index values into sarcopenia (lower third) and nonsarcopenia (upper two-thirds) groups. Multivariable modeling identified operative mortality and spinal cord injury predictors. Unadjusted and adjusted survival curves were analyzed.

RESULTS

Of 392 patients identified, those with sarcopenia (n = 131) were older than nonsarcopenic patients (n = 261) (70.0 years vs 68.0 years; P = .02) and more frequently presented with aortic rupture or required urgent/emergency operations. Operative mortality was comparable (sarcopenia 13.7% vs nonsarcopenia 10.0%; P = .3); sarcopenia was not associated with operative mortality in the multivariable model (odds ratio, 1.40; 95% confidence interval, 0.73-2.77; P = .3). Sarcopenic patients experienced more frequent delayed (13.0% vs 4.6%; P = .005) and persistent (10.7% vs 3.4%; P = .008) paraplegia. Sarcopenia independently predicted delayed paraplegia (odds ratio, 3.17; 95% confidence interval, 1.42-7.08; P = .005) and persistent paraplegia (odds ratio, 3.29; 95% confidence interval, 1.33-8.13; P = .01) in the multivariable model. Adjusted for preoperative/operative covariates, midterm survival was similar for sarcopenic and nonsarcopenic patients (P = .3).

CONCLUSIONS

Sarcopenia did not influence early mortality or midterm survival after thoracoabdominal aortic aneurysm repair but was associated with greater risk for delayed and persistent paraplegia.

Sarcopenia predicts worse postoperative outcomes and decreased survival rates in patients with colorectal cancer: a systematic review and meta-analysis

PURPOSE

Previous studies have shown an association of sarcopenia with adverse short- and long-term outcomes in multiple gastrointestinal cancer types. We aimed to investigate the prognostic value of sarcopenia on the postoperative outcomes and survival rates of patients with colorectal cancer (CRC).

METHODS

A systematic literature search was performed using the PubMed, Embase, Cochrane, Google Scholar, and Scopus databases. We included studies that compared postoperative outcomes or survival rates in sarcopenic and non-sarcopenic patients with CRC.

RESULTS

A total of 44 observational studies, comprising 18,891 patients, were included. The pooled prevalence of sarcopenia was 37% (n = 7009). The pooled analysis revealed an association between sarcopenia and higher risk of total postoperative complications (23 studies, OR = 1.84; 95% CI 1.35-2.49), postoperative severe complications (OR = 1.72; 95% CI 1.10-2.68), postoperative mortality (OR = 3.21; 95% CI 2.01-5.11), postoperative infections (OR = 1.40; 95% CI 1.12-1.76), postoperative cardiopulmonary complications (OR = 2.92; 95% CI 1.96-4.37), and prolonged length of stay (MD = 0.77; 95% CI 0.44-1.11) after colorectal cancer surgery. However, anastomotic leakage showed comparable occurrence between sarcopenic and non-sarcopenic patients (OR = 0.99; 95% CI 0.72 to 1.36). Regarding survival outcomes, sarcopenic patients had significantly shorter overall survival (25 studies, HR = 1.83; 95% CI = 1.57-2.14), disease-free survival (HR = 1.55; 95% CI = 1.29-1.88), and cancer-specific survival (HR = 1.77; 95% CI 1.40-2.23) as compared with non-sarcopenic patients.

CONCLUSION

Among patients with colorectal cancer, sarcopenia is a strong predictor of increased postoperative complications and worse survival outcomes.

Risk factors for surgery-related muscle quantity and muscle quality loss and their impact on outcome

Background

Surgery-related loss of muscle quantity negatively affects postoperative outcomes. However, changes of muscle quality have not been fully investigated. A perioperative intervention targeting identified risk factors could improve postoperative outcome. This study investigated risk factors for surgery-related loss of muscle quantity and quality and outcomes after liver resection for colorectal liver metastasis (CRLM).

Methods

Data of patients diagnosed with CRLM who underwent liver resection between 2006 and 2016 were analysed. Muscle quantity (psoas muscle index [PMI]), and muscle quality, (average muscle radiation attenuation [AMA] of the psoas), were measured using computed tomography. Changes in PMI and AMA of psoas after surgery were assessed.

Results

A total of 128 patients were analysed; 67 (52%) had surgery-related loss of muscle quantity and 83 (65%) muscle quality loss. Chronic obstructive pulmonary disease (COPD) (P = 0.045) and diabetes (P = 0.003) were risk factors for surgery-related loss of muscle quantity. A higher age (P = 0.002), open resection (P = 0.003) and longer operation time (P = 0.033) were associated with muscle quality loss. Overall survival was lower in patients with both muscle quantity and quality loss compared to other categories (P = 0.049). The rate of postoperative complications was significantly higher in the group with surgery-related loss of muscle quality.

Conclusions

Risk factors for surgery-related muscle loss were identified. Overall survival was lowest in patients with both muscle quantity and quality loss. Complication rate was higher in patients with surgery-related loss of muscle quality.

Phenotypic features of cancer cachexia-related loss of skeletal muscle mass and function: lessons from human and animal studies

Cancer cachexia is a complex multi-organ catabolic syndrome that reduces mobility, increases fatigue, decreases the efficiency of therapeutic strategies, diminishes the quality of life, and increases the mortality of cancer patients. This review provides an exhaustive and comprehensive analysis of cancer cachexia-related phenotypic changes in skeletal muscle at both the cellular and subcellular levels in human cancer patients, as well as in animal models of cancer cachexia. Cancer cachexia is characterized by a major decrease in skeletal muscle mass in human and animals that depends on the severity of the disease/model and the localization of the tumour. It affects both type 1 and type 2 muscle fibres, even if some animal studies suggest that type 2 muscle fibres would be more prone to atrophy. Animal studies indicate an impairment in mitochondrial oxidative metabolism resulting from a decrease in mitochondrial content, an alteration in mitochondria morphology, and a reduction in mitochondrial metabolic fluxes. Immuno-histological analyses in human and animal models also suggest that a faulty mechanism of skeletal muscle repair would contribute to muscle mass loss. An increase in collagen deposit, an accumulation of fat depot outside and inside the muscle fibre, and a disrupted contractile machinery structure are also phenotypic features that have been consistently reported in cachectic skeletal muscle. Muscle function is also profoundly altered during cancer cachexia with a strong reduction in skeletal muscle force. Even though the loss of skeletal muscle mass largely contributes to the loss of muscle function, other factors such as muscle-nerve interaction and calcium handling are probably involved in the decrease in muscle force. Longitudinal analyses of skeletal muscle mass by imaging technics and skeletal muscle force in cancer patients, but also in animal models of cancer cachexia, are necessary to determine the respective kinetics and functional involvements of these factors. Our analysis also emphasizes that measuring skeletal muscle force through standardized tests could provide a simple and robust mean to early diagnose cachexia in cancer patients. That would be of great benefit to cancer patient's quality of life and health care systems.

A Low Total Psoas Muscle Area Index Is a Strong Prognostic Factor in Metastatic Pancreatic Cancer

OBJECTIVES

The total psoas area index (TPI) is an emerging alternative to the total skeletal muscle area index as a prognostic factor but has never been evaluated in metastatic pancreatic cancer (mPC).

METHODS

Areas were manually recorded, as previously described. Sex-specific cutoffs were identified by optimum stratification of TPI using log-rank χ2 statistic associated with mortality to define sarcopenic psoas. Progression-free survival (PFS) and overall survival (OS) were the primary objectives. Two period groups were used as internal validation.

RESULTS

During the period study, 79 patients were treated for mPC. The TPI was correlated with PFS (hazards ratio, 0.81; P = 0.02) and OS (hazards ratio, 0.7; P < 0.001). Optimum thresholds defining sarcopenic psoas were less than 5.73 cm2/m2 in men and less than 4.37 cm2/m2 in women. Patients with sarcopenic psoas (62.0%) had shorter median PFS (2.9 months) compared with the others (6.6 months, adjusted P log-rank = 0.01), independently to the intensity of chemotherapy, weight loss, and performance status greater than 1. Similarly, OS was independently shorter in patients with sarcopenic psoas (7.6 months) versus the others (22.2 months, adjusted P < 0.001). These results were confirmed in the 2 period groups.

CONCLUSIONS

A low TPI is a stronger independent prognostic factor in mPC.

Sarcopenia and mortality in different clinical conditions: A meta-analysis

OBJECTIVES

Sarcopenia is recognized to be a health problem which is as serious as obesity, but its relevance to mortality is unclear. We conducted a meta-analysis of cohort studies on lean mass and mortality in populations with different health conditions.

METHODS

In this study, a systematic search of PubMed, Cochrane Library and Embase was performed for cohort studies published before Dec 20, 2017 which examined the relationship between lean mass and mortality. We included studies reporting lean mass measurement by dual-energy X-ray absorptiometry, bioimpedance analysis or computed tomography, as continuous (per standard deviation [SD] decrease) or binary variables (using sarcopenia cutoffs). We excluded studies which used muscle mass surrogates, anthropometric measurement of muscle, rate of change in muscle mass, and sarcopenia defined by composite criteria. The primary study outcome was all-cause mortality. Pooled hazard ratio estimates were calculated using a random effects model.

RESULTS

A total of 9602 articles were identified from the systematic search, and 188 studies with 98 468 participants from 34 countries were included in the meta-analysis. Of the 68 studies included in the present meta-analysis, the pooled HR was 1.36 and 1.74 for every SD decrease in lean mass and in people with low lean mass (cutoffs), respectively. Significant associations were also observed in elderly and all disease subgroups, irrespective of the measurement modalities.

CONCLUSIONS

Lower lean mass is robustly associated with increased mortality, regardless of health conditions and lean mass measurement modalities. This meta-analysis highlighted low lean mass as a key public health issue.

Sarcopenia and Myosteatosis Predict Adverse Outcomes After Emergency Laparotomy: A Multi-Centre Observational Cohort Study

OBJECTIVE

To determine the relationship between body composition (BC), specifically low skeletal muscle mass (sarcopenia) and poor muscle quality (myosteatosis) and outcomes in emergency laparotomy patients.

BACKGROUND

Emergency laparotomy has one of the highest morbidity and mortality rates of all surgical interventions. BC objectively identifies patients at risk of adverse outcomes in elective cancer cohorts, however evidence is lacking in emergency surgery.

METHODS

An observational cohort study of patients undergoing emergency laparotomy at ten English hospitals was performed. BC analyses were performed at the third lumbar vertebrae level using pre-operative CT images to quantify skeletal muscle index (SMI) and skeletal muscle radiation attenuation (SM-RA). Sex-specific SMI and SM-RA were determined, with the lower tertile splits defining sarcopenia (low SMI) and myosteatosis (low SM-RA). Accuracy of mortality risk prediction, incorporating SMI and SM-RA variables into risk models was assessed with regression modelling.

RESULTS

Six hundred and ten patients were included. Sarcopenia and myosteatosis were both associated with increased risk of morbidity (52.1% vs. 45.1%, p = 0.028; 57.5% vs. 42.6%, p = 0.014), 30-day (9.5% vs. 3.6%, p = 0.010; 14.9% vs. 3.4%, p < 0.001), and 1-year mortality (27.4% vs. 11.5%, p < 0.001; 29.7% vs.12.5%, p < 0.001). Risk-adjusted 30-day mortality was significantly increased by sarcopenia (OR 2.56 (95%CI 1.12-5.84), p = 0.026) and myosteatosis (OR 4.26 (2.01-9.06), p < 0.001), similarly at 1-year (OR 2.66 (95%CI 1.57-4.52), p < 0.001; OR 2.08 (95%CI 1.26-3.41), p = 0.004). BC data increased discrimination of an existing mortality risk-prediction model (AUC 0.838, 95%CI 0.835-0.84).

CONCLUSION

Sarcopenia and myosteatosis are associated with increased adverse outcomes in emergency laparotomy patients.

Preoperative standardized phase angle at bioimpedance vector analysis predicts the outbreak of antimicrobial-resistant infections after major abdominal oncologic surgery: A prospective trial

OBJECTIVES

Infectious morbidity is the most common and costly among all surgery-related complications, and infections by multidrug-resistant microorganisms (MDR) are associated with poor outcomes. Derangements of body composition is a recognized risk factor for infections. The aim of this study was to investigate the potential association between specific traits of body composition and the risk of having MDR-related infections.

METHODS

This was a prospective study with patients scheduled for major abdominal surgery for gastrointestinal cancer. Bioimpedance vector analysis (BIVA), a reliable tool for body composition assessment, was performed the day before the operation. Postoperative complications were collected focusing on resistance patterns and site of infection. Patterns of resistance were compared with BIVA parameters.

RESULTS

Data from 182 patients suffering from pancreatic (n = 76, 41.7%), rectal (n = 38, 20.9%), gastric (n = 31, 17%), or hepatic (n = 37, 20.3%) malignancy were collected. Overall complications occurred in 108 patients (59%), and in 45 patients (28%) bacterial infections were proven at culture. Of these, 15 (8%) were multidrug-sensitive (MDS), 38 MDR, and 2 extended drug-resistant (XDR) infections. The standardized phase angle measured (SPA) at BIVA was significantly lower in the MDR/XDR infections (-0.02 ± 1.20) than for no infection/MDS (0.56 ± 1.53; P = 0.029). A multivariate analysis showed that SPA was the only independent variable for MDR/XDR infections with an odds ratio of 3.057 (95% confidence interval, 1.354-6903; P = 0.007). The predictive ability of SPA revealed an area under the receiver operating characteristic curve of 0.662, with an optimal threshold of -0.3.

CONCLUSIONS

In surgical cancer patients, preoperative value of SPA lower than -0.3 is associated with the outbreak of MDR bacterial infections.

Is sarcopenia really a risk factor in the development of postoperative complications?

PURPOSE

This study was aimed to evaluate the impact of sarcopenia, which was defined by total psoas area (TPA) and total psoas volume (TPV) measurements, on the development of major postoperative complications.

MATERIAL-METHODS

Sarcopenia was assessed in 225 patients with gastrointestinal cancer who underwent surgery between October 2015 and March 2020. The impact of sarcopenia defined by TPA and TPV on major postoperative complications was assessed using multivariate analysis.

RESULTS

Both the median TPA and TPV were higher in men than that in women (p < 0.001). The cut-off value of TPA to define sarcopenia was 526.5 mm²/m² and 495.68 mm²/m² for men and women, respectively, and the cut-off value of TPV was 79.6 cm³/m² for men and 83.1 cm³/m² for women, While 102 patients (45.3%) had sarcopenia defined by TPA, 54 (24%) had sarcopenia defined by TPV. Seventy-eight patients had at least one complication; 36 (46%) had major complications, and 15 patients died during the study. In logistic regression analysis, only sex was found as a risk factor for the development of sarcopenia (OR = 13.403, p = 0.014). There was a positive correlation between TPA and TPV in male and female patients separately (r = 0.841 and r = 0.883, respectively, p < 0.001). Only sarcopenia defined by TPV was found as a risk factor for the development of major postoperative complication (OR: 35.349, p = 0.028).

CONCLUSION

Sarcopenia defined by TPV is an independent risk factor in predicting major postoperative complications, not TPA. We believe that volume measurement instead of area is a more accurate method for evaluating sarcopenia in gastrointestinal cancer surgery.

Visceral obesity and muscle mass determined by CT scan and surgical outcome in patients with advanced ovarian cancer. A retrospective cohort study

OBJECTIVE

Visceral obesity (VO) is a risk factor for developing postoperative complications in patients undergoing abdominal oncological surgery. However, in ovarian cancer patients this influence of body composition on postoperative morbidity is not well established. The aim of this study is to assess the association between body composition and complications in patients with advanced ovarian cancer undergoing cytoreductive surgery.

METHODS

Patients with FIGO stage 3 or 4 ovarian cancer between 2006 and 2017 were included. Visceral fat area, total skeletal mass and total fat area were measured on a single slice on the level of L3-L4 of the preoperative CT-scan. VO was defined as visceral fat ≥100cm². The perioperative data were extracted retrospectively. A multivariate logistic regression analysis was performed to test the predictive value of multiple variables such as body composition, albumin levels and preoperative morbidity.

RESULTS

298 consecutive patients out of nine referring hospitals were included. VO patients were more likely to be hypertensive (38% vs 17% p < 0.001), and to have an ASA 3 score (21% vs 10% P = 0.012). Complications occurred more often in VO patients (43% vs 21% P < 0.001). Thrombotic events were found in 4.9% of VO patients versus 0.6% of the non-visceral obese patients (p = 0.019). VO(OR: 4.37, p < 0.001), hypertension (OR:1.9, p = 0.046) and duration of surgery (OR: 1.004, p = 0.017) were predictors of post-surgical complications. Muscle mass is not a predictor of complications.

CONCLUSION

Visceral obesity is associated with a higher occurrence of complications in patients with advanced ovarian cancer undergoing cytoreductive surgery.

Prognostic Value of Psoas Muscle Mass Index in Patients With Non‒ST-Segment‒Elevation Myocardial Infarction: A Prospective Observational Study

Background Muscle wasting is an important predictor of long-term outcome in patients with cardiovascular disease, but the prognostic value of muscle wasting in patients with non‒ST-segment‒elevation myocardial infarction is not established. The aim of this study is to investigate the prognostic value of muscle wasting, defined by psoas muscle mass index (PMI), in patients with non‒ST-segment‒elevation myocardial infarction. Methods and Results A total of 132 consecutive patients with non‒ST-segment‒elevation myocardial infarction were prospectively enrolled between 2015 and 2018. Primary end point was incidence of cardiovascular events including cardiovascular deaths, non-fatal myocardial infarction, or non-fatal stroke. Cross-sectional area of the psoas muscle at the L3 vertebral level was obtained by computed tomography and PMI was calculated. The median follow-up period was 2.4 years (interquartile range, 1.1-4.0 years). There were 45 cardiovascular events (34%) during the study periods. The optimal cutoff value of PMI to predict cardiovascular events was 772 mm2/m2, as assessed by receiver operating curve analysis. Patients with reduced PMI (PMI<772 mm2/m2) had significantly higher cardiovascular events than those with preserved PMI (PMI≥772 mm2/m2) (48% versus 21%; log-rank test P<0.001). Multivariate Cox proportional hazards model revealed that reduced PMI was a statistically significant predictor of cardiovascular events (hazard ratio, 3.30; 95% CI, 1.70-6.40; P<0.001). Conclusions Muscle wasting defined as PMI is a simple and useful objective marker to predict future cardiovascular outcome in patients with non‒ST-segment‒elevation myocardial infarction. Registration Information URL: https://www.umin.ac.jp/ctr/; Unique identifier: UMIN000013445.

New insights on how and where to measure muscle mass

PURPOSE OF REVIEW

This article will discuss different muscle mass assessment methods and emphasize their highlights.

RECENT FINDINGS

Several measurement techniques can be used to evaluate muscle mass, recognized as important prognostic markers for adverse functional and clinical outcomes. Choosing the best method depends on the knowledge regarding their theoretical and practical limitations and the purpose of the assessment. Image techniques are considered the gold standards, with good accuracy and precision, but not always available in clinical settings. A new biological technique, the D3-creatinine dilution, can provide not only direct information about muscle mass but also shows a strong association with physical function. With the advancement of the use of the computed tomography (CT) images to assess skeletal muscle mass, mainly in patients with cancer, the assessment of skeletal muscle radiodensity (SMD), as a marker of muscle quality, may provide additional information regarding the association between muscle composition, muscle function and prognosis. Additional muscle function assessment can improve the risk prediction in several clinical situations.

SUMMARY

The use of the best tool for the muscle mass assessment should be performed carefully among the various methodologies, according to their characteristics and clinical situation.

Psoas muscle area and attenuation are highly predictive of complications and mortality after complex endovascular aortic repair

OBJECTIVE

The present study evaluated the psoas muscle area and attenuation (radiodensity), quantified by computed tomography, together with clinical risk assessment, as predictors of outcomes after fenestrated and branched endovascular aortic repair (FBEVAR).

METHODS

The present single-center study included 504 patients who had undergone elective FBEVAR for pararenal or thoracoabdominal aortic aneurysms. The clinical risk assessment included age, sex, comorbidities, body mass index, glomerular filtration rate, aneurysm size and extent, cardiac stress test results, ejection fraction, and American Society of Anesthesiologists (ASA) score. Preoperative computed tomography was used to measure the psoas muscle area and attenuation at the L3 level. The lean psoas muscle area (LPMA; area in cm² multiplied by attenuation in Hounsfield units [HU]) was calculated by multiplying the area by the attenuation. The risk factors for 90-day mortality, major adverse events (MAEs), and long-term mortality were determined using multivariable analysis. MAEs included 30-day or in-hospital death, acute kidney injury, myocardial infarction, respiratory failure, paraplegia, stroke, and bowel ischemia. A novel risk stratification method was proposed according to the strongest predictors of mortality and MAEs on multivariable analysis.

RESULTS

The 30-day mortality, 90-day mortality, and MAE rates were 2.0%, 5.6%, and 20%, respectively. The independent predictors of 90-day mortality were chronic obstructive pulmonary disease, chronic kidney disease, ASA score, and LPMA. The independent predictors of MAEs were aneurysm diameter, glomerular filtration rate, and LPMA. For long-term mortality, the independent predictors were chronic kidney disease, congestive heart failure, extent I-III thoracoabdominal aortic aneurysms, ASA score, and LPMA. The patients were stratified into three groups according to the ASA score and LPMA: low risk, ASA score II or LPMA >350 cm²HU (n = 290); medium risk, ASA score III and LPMA ≤350 cm²HU (n = 181); and high risk, ASA score IV and LPMA ≤350 cm²HU (n = 33). The 90-day mortality and MAE rates were 1.7% and 16% in the low-, 7.2% and 24% in the medium-, and 30% and 33% in the high-risk patients, respectively (P < .001 and P = .02, respectively). Patients with ASA score IV and LPMA <200 cm²HU, indicating sarcopenia (n = 14) had a 43% risk of death within 90 days. The 3-year survival estimates were 80% ± 3% for the low-, 70% ± 4% for the medium-, and 35% ± 9% for the high-risk patients (P < .001). The mean follow-up time was 3.1 ± 2.3 years.

CONCLUSIONS

LPMA was a strong predictor of outcomes and the only independent predictor of both mortality and MAEs after FBEVAR. A high muscle mass was protective against complications, regardless of the ASA score. Risk stratification based on the ASA score and LPMA can be used to identify patients at excessively high operative risk.

Loss of skeletal muscle mass predicts cardiac death in heart failure with a preserved ejection fraction but not heart failure with a reduced ejection fraction

Aims

Loss of skeletal muscle mass is an important determinant associated with poor long‐term prognosis in patients with acute decompensated heart failure (ADHF). However, limited evidence is available. This study investigated the prognostic value of the psoas muscle mass index (PMI) in patients with ADHF.

Methods and results

A total of 210 consecutive patients aged ≥60 years with ADHF were enrolled using a prospective database between 2015 and 2017. Primary endpoint was incidence of cardiac death. Cross‐sectional psoas muscle area at the L3 vertebral level was obtained by computed tomography, and PMI was calculated by height. Reduced PMI was defined as a PMI below the 25th sex‐specific percentile. Patients were also classified by their left ventricular ejection fraction (EF) as having either heart failure with a reduced ejection fraction (HFrEF, EF < 50%) or heart failure with a preserved ejection fraction (HFpEF, EF ≥ 50%). The median follow‐up period was 1.8 years. There were 44 cardiac deaths (21%) during the study period. Patients with reduced PMI had significantly higher cardiac death rates than those with preserved PMI (33% vs. 17%, log‐rank test P = 0.006). In subgroup analysis, HFpEF patients with reduced PMI had significantly higher cardiac death rates than those with preserved PMI (38% vs. 16%, log‐rank test P = 0.006); conversely, HFrEF patients had comparable cardiac death rates regardless of their PMI group (27% for reduced PMI vs. 18% for preserved PMI, log‐rank test P = 0.24). Multivariate Cox proportional hazards model revealed that patients with reduced PMI had a 2.3‐fold higher risk of cardiac death compared with patients with preserved PMI (95% confidence interval 1.23–4.42, P = 0.01).

Conclusions

Reduced PMI helps to predict long‐term outcome in patients with HFpEF but not HFrEF.

Low skeletal muscle mass and postoperative morbidity in surgical oncology: a systematic review and meta-analysis

BACKGROUND

Sarcopenia might function as an indicator for frailty, and as such as a risk factor for the development of postoperative complications. The aim of this study was to meta-analyse the relation between preoperative sarcopenia and the development of severe postoperative complications in patients undergoing oncological surgery.

METHODS

PubMed and Embase databases were systematically searched from inception until May 2018. Included were studies reporting on the incidence of severe postoperative complications and radiologically determined preoperative sarcopenia. Studies reporting the skeletal muscle as a continuous variable only were excluded. Data were extracted independently by two reviewers. Random effect meta-analyses were applied to estimate the pooled odds ratio (OR) with 95% confidence intervals (95% CI) for severe postoperative complications, defined as Clavien-Dindo grade ≥3, including 30-day mortality. Heterogeneity was evaluated with I2 testing. Analyses were performed overall and stratified by measurement method, tumour location and publication date.

RESULTS

A total of 1924 citations were identified, and 53 studies (14 295 patients) were included in the meta-analysis. When measuring the total skeletal muscle area, 43% of the patients were sarcopenic, versus 33% when measuring the psoas area. Severe postoperative complications were present in 20%, and 30-day mortality was 3%. Preoperative sarcopenia was associated with an increased risk of severe postoperative complications (ORpooled : 1.44, 95% CI: 1.24-16.8, P<0.001, I2 =55%) and 30-day mortality (ORpooled : 2.15, 95% CI: 1.46-3.17, P<0.001, I2 =14%). A low psoas mass was a stronger predictor for severe postoperative complications compared with a low total skeletal muscle mass (ORpooled : 2.06, 95% CI: 1.37-3.09, ORpooled : 1.32, 95% CI: 1.14-1.53, respectively) and 30-day mortality [ORpooled : 6.17 (95% CI: 2.71-14.08, ORpooled : 1.80 (95% CI: 1.24-2.62), respectively]. The effect was independent of tumour location and publication date.

CONCLUSIONS

The presence of low psoas mass prior to surgery, as an indicator for sarcopenia, is a common phenomenon and is a strong predictor for the development of postoperative complications. The presence of low total skeletal muscle mass, which is even more frequent, is a less informative predictor for postoperative complications and 30-day mortality. The low heterogeneity indicates that the finding is consistent over studies. Nevertheless, the value of sarcopenia relative to other assessments such as frailty screening is not clear. Research is needed in order to determine the place of sarcopenia in future preoperative risk stratification.