One-year postoperative resource utilization in sarcopenic patients

Acute Muscle Mass Loss Predicts Long-Term Fatigue, Myalgia, and Health Care Costs in COVID-19 Survivors

OBJECTIVE

We examined the impact of loss of skeletal muscle mass in post-acute sequelae of SARS-CoV-2 infection, hospital readmission rate, self-perception of health, and health care costs in a cohort of COVID-19 survivors.

DESIGN

Prospective observational study.

SETTING AND PARTICIPANTS

Tertiary Clinical Hospital. Eighty COVID-19 survivors age 59 ± 14 years were prospectively assessed.

METHODS

Handgrip strength and vastus lateralis muscle cross-sectional area were evaluated at hospital admission, discharge, and 6 months after discharge. Post-acute sequelae of SARS-CoV-2 were evaluated 6 months after discharge (main outcome). Also, health care costs, hospital readmission rate, and self-perception of health were evaluated 2 and 6 months after hospital discharge. To examine whether the magnitude of muscle mass loss impacts the outcomes, we ranked patients according to relative vastus lateralis muscle cross-sectional area reduction during hospital stay into either "high muscle loss" (-18 ± 11%) or "low muscle loss" (-4 ± 2%) group, based on median values.

RESULTS

High muscle loss group showed greater prevalence of fatigue (76% vs 46%, P = .0337) and myalgia (66% vs 36%, P = .0388), and lower muscle mass (-8% vs 3%, P < .0001) than low muscle loss group 6 months after discharge. No between-group difference was observed for hospital readmission and self-perceived health (P > .05). High muscle loss group demonstrated greater total COVID-19-related health care costs 2 ($77,283.87 vs. $3057.14, P = .0223, respectively) and 6 months ($90,001.35 vs $12, 913.27, P = .0210, respectively) after discharge vs low muscle loss group. Muscle mass loss was shown to be a predictor of total COVID-19-related health care costs at 2 (adjusted β = $10, 070.81, P < .0001) and 6 months after discharge (adjusted β = $9885.63, P < .0001).

CONCLUSIONS AND IMPLICATIONS

COVID-19 survivors experiencing high muscle mass loss during hospital stay fail to fully recover muscle health. In addition, greater muscle loss was associated with a higher frequency of post-acute sequelae of SARS-CoV-2 and greater total COVID-19-related health care costs 2 and 6 months after discharge. Altogether, these data suggest that the loss of muscle mass resulting from COVID-19 hospitalization may incur in an economical burden to health care systems.

Does sarcopenia affect outcomes in pediatric surgical patients? A scoping review

OBJECTIVE

Adults with sarcopenia have a greater risk of postoperative complications, a higher rate of ICU admission, and an increased length of hospital stay. Few studies have explored the prevalence or importance of sarcopenia in the pediatric population. This study reviews the published literature on sarcopenia in the pediatric population, including pediatric surgery.

METHODS

Original studies related to sarcopenia in children were identified using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines and the PubMed database.

RESULTS

A total of 390 articles were screened, with 28 meeting inclusion criteria. Twenty (71%) studies provided a means to define abnormal and 18 studies (64%) showed that a specific disease process could impact lean muscle mass in children. Only 4 (14%) studies associated the change in muscle mass with an outcome. Two studies investigated sarcopenia and outcomes in the pediatric surgical patient and demonstrated associations with worse outcomes.

CONCLUSION

Despite studies showing an association between sarcopenia and negative outcomes in the adult surgical population, there remains a paucity of evidence regarding the impact of sarcopenia on the pediatric population. Future studies are needed to ascertain the relationship between muscle mass and outcomes in pediatric surgical patients.

Nutrition in Cancer Therapy: Overview for the Cancer Patient

Despite significant advances in oncologic treatment, cancer-associated metabolic derangements remain largely poorly understood and often neglected in cancer care. Cancer cachexia and metabolic changes exhibited by neoplastic cells pose formidable barriers to improving outcomes and quality of life. Although cancer has traditionally been viewed as a proliferative disease caused by genetic mutations, newer perspectives suggest that it is primarily a metabolic disease. This paper discusses the etiology of cachexia and sarcopenia, and nutritional interventions that can address these wasting disorders. The role of inflammation in cancer and the methods for preventing and resolving inflammation with nutrition intervention are also explored. Several nutritional recommendations aimed at overcoming cachexia, resolving inflammation and improving cancer outcomes are provided based on current literature. This manuscript selected only a few areas in which to focus and is not all inclusive of the expansive literature available on the topic of cachexia. This article is protected by copyright. All rights reserved.

Paradigm shift in gastrointestinal surgery − combating sarcopenia with prehabilitation: Multimodal review of clinical and scientific data

A growing body of evidence has demonstrated the prognostic significance of sarcopenia in surgical patients as an independent predictor of postoperative complications and outcomes. These included an increased risk of total complications, major complications, re-admissions, infections, severe infections, 30 d mortality, longer hospital stay and increased hospitalization expenditures. A program to enhance recovery after surgery was meant to address these complications; however, compliance to the program since its introduction has been less than ideal. Over the last decade, the concept of prehabilitation, or “pre-surgery rehabilitation”, has been discussed. The presurgical period represents a window of opportunity to boost and optimize the health of an individual, providing a compensatory “buffer” for the imminent reduction in physiological reserve post-surgery. Initial results have been promising. We review the literature to critically review the utility of prehabilitation, not just in the clinical realm, but also in the scientific realm, with a resource management point-of-view.

The emerging role of sarcopenia as a prognostic indicator in patients undergoing abdominal wall hernia repairs: a systematic review of the literature

BACKGROUND

There is strong evidence suggesting that excessive fat distribution, for example, in the bowel mesentery or a reduction in lean body mass (sarcopenia) can influence short-, mid-, and long-term outcomes from patients undergoing various types of surgery. Body composition (BC) analysis aims to measure and quantify this into a parameter that can be used to assess patients being treated for abdominal wall hernia (AWH). This study aims to review the evidence linking quantification of BC with short- and long-term abdominal wall hernia repair outcomes.

METHODS

A systematic review was performed according to the PRISMA guidelines. The literature search was performed on all studies that included BC analysis in patients undergoing treatment for AWH using Medline, Google Scholar and Cochrane databases by two independent reviewers. Outcomes of interest included short-term recovery, recurrence outcomes, and long-term data.

RESULTS

201 studies were identified, of which 4 met the inclusion criteria. None of the studies were randomized controlled trials and all were cohort studies. There was considerable variability in the landmark axial levels and skeletal muscle(s) chosen for analysis, alongside the methods of measuring the cross-sectional area and the parameters used to define sarcopenia. Only two studies identified an increased risk of postoperative complications associated with the presence of sarcopenia. This included an increased risk of hernia recurrence, postoperative ileus and prolonged hospitalisation.

CONCLUSION

There is some evidence to suggest that BC techniques could be used to help predict surgical outcomes and allow early optimisation in AWH patients. However, the lack of consistency in chosen methodology, combined with the outdated definitions of sarcopenia, makes drawing any conclusions difficult. Whether body composition modification can be used to improve outcomes remains to be determined.

Skeletal muscle size, function, and adiposity with lifelong aerobic exercise

We examined the influence of lifelong aerobic exercise on skeletal muscle size, function, and adiposity. Young exercisers [YE; n = 20, 10 women (W), 25 ± 1 yr], lifelong exercisers (LLE; n = 28, 7 W, 74 ± 2 yr), and old healthy nonexercisers (OH; n = 20, 10 W, 75 ± 1 yr) were studied. On average, LLE exercised 5 days/wk for 7 h/wk over the past 52 ± 1 yr. The LLE men were subdivided by exercise intensity [Performance (LLE-P), n = 14; Fitness (LLE-F), n = 7]. Upper and lower leg muscle size and adiposity [intermuscular adipose tissue (IMAT)] were determined via MRI, and quadriceps isotonic and isometric function was assessed. For the quadriceps, aging decreased muscle size, isotonic and isometric strength, contraction velocity (men only), and power (P < 0.05). In women, LLE did not influence muscle size or function. In men, LLE attenuated the decline in muscle size and isometric strength by ~50% (P < 0.05). LLE did not influence other aspects of muscle function, nor did training intensity influence muscle size or function. For the triceps surae, aging decreased muscle size only in the women, whereas LLE (both sexes) and training intensity (LLE men) did not influence muscle size. In both sexes, aging increased thigh and calf IMAT by ~130% (P < 0.05), whereas LLE attenuated the thigh increase by ~50% (P < 0.05). In the LLE men, higher training intensity decreased thigh and calf IMAT by ~30% (P < 0.05). In summary, aging and lifelong aerobic exercise influenced muscle size, function, and adipose tissue infiltration in a sex- and muscle-specific fashion. Higher training intensity throughout the life span provided greater protection against adipose tissue infiltration into muscle.NEW & NOTEWORTHY This is the first study to examine skeletal muscle size, function, and adiposity in women and men in their eighth decade of life that have engaged in lifelong aerobic exercise. The findings reveal sex and upper and lower leg muscle group-specific benefits related to skeletal muscle size, function, and adiposity and that exercise intensity influences intermuscular adiposity. This emerging cohort will further our understanding of the health implications of maintaining exercise throughout the life span.

Usefulness of skeletal muscle area detected by computed tomography to predict mortality in patients undergoing transcatheter aortic valve replacement: a meta-analysis study

Measures of sarcopenia, such as low muscle mass measured from the readily available preoperative computed tomography (CT) images, have been recently suggested as a predictor of outcomes in patients undergoing transcatheter aortic valve replacement (TAVR). However, results of these studies are variable and, therefore, we performed a systematic review of current literature to evaluate sarcopenia as a predictor of outcome post TAVR. The search was carried out in electronic databases between 2008 and 2018. We identified studies that reported CT-derived skeletal muscle area (SMA) and survival outcomes post TAVR. Studies were evaluated for the incidence of early (≤ 30 days) and late all-cause mortality (> 30 days) post TAVR. Eight studies with 1881 patients were included (mean age of 81.8 years ± 12, 55.9% men). Mean body mass index was (28.2 kg/m² ± 1.1), mean Society of Thoracic Surgeons risk score (7.0 ± 0.6), and mean albumin level was (3.8 g/dL ± 0.1). Higher SMA was associated with lower long-term mortality [odds ratio (OR) 0.49, 95% confidence interval (CI) 0.28-0.83, p = 0.049], compared with low SMA. Also, higher SMA was associated with lower early mortality but was not statistically significant (OR 0.72; 95% CI 0.44-1.18; p = 0.285). CT-derived SMA provides value in predicting post-TAVR long-term outcomes for patients undergoing TAVR. This is a simple risk assessment tool that may help in making treatment decisions and help identifying and targeting high-risk patients with interventions to improve muscle mass prior to and following the procedures.

Financial impact of sarcopenia or low muscle mass - A short review

BACKGROUND & AIMS

Low muscle mass is associated with increased falls, medical complications, length of hospital stay and loss of independence. An increasing number of studies has also shown the association between sarcopenia and health care expenditure. The following narrative review summarizes the current evidence on the economic relevance of low muscle mass (MM) or sarcopenia.

METHODS

An extensive search of the literature in Medline identified twelve studies in English, which evaluated direct and indirect health care expenditure in patients with low muscle mass or sarcopenia (low MM and strength or mobility).

RESULTS

Three studies analysed the cost of age-related loss of MM or strength in large surveys of the general, older population. Six retrospective analyses evaluated perioperative medical costs related to low MM in primarily older patients from different medical areas. One prospective study presented hospital costs related to sarcopenia in patients with gastric cancer. Two studies presented data from general hospital patients. Despite the difference in diagnostic criteria, study population and statistical design, low MM and sarcopenia were consistently identified as predictors of increased health care expenditure in community, perioperative and general hospital settings.

CONCLUSIONS

Low MM and sarcopenia are prevalent and associated with significantly higher health care costs. Considering the demographic change, which will lead to an increasing number of patients with sarcopenia, every effort should be made to identify and treat patients with sarcopenia. The use of a unified definition and diagnostic criteria would allow a better comparison of data.

Assessment of Computed Tomography (CT)-Defined Muscle and Adipose Tissue Features in Relation to Short-Term Outcomes After Elective Surgery for Colorectal Cancer: A Multicenter Approach

BACKGROUND

Sarcopenia, visceral obesity (VO), and reduced muscle radiodensity (myosteatosis) are suggested risk factors for postoperative morbidity in colorectal cancer (CRC), but usually are not concurrently assessed. Published thresholds used to define these features are not CRC-specific and are defined in relation to mortality, not postoperative outcomes. This study aimed to evaluate body composition in relation to length of hospital stay (LOS) and postoperative outcomes.

METHODS

Pre-surgical computed tomography (CT) images were assessed for total area and radiodensity of skeletal muscle and visceral adipose tissue in a pooled Canadian and UK cohort (n = 2100). Sex- and age-specific values for these features were calculated. For 1139 of 2100 patients, LOS data were available, and sex- and age-specific thresholds for sarcopenia, myosteatosis, and VO were defined on the basis of LOS. Association of CT-defined features with LOS and readmissions was explored using negative binomial and logistic regression models, respectively.

RESULTS

In the multivariable analysis, the predictors of LOS (P < 0.001) were age, surgical approach, major complications (incidence rate ratio [IRR] 2.42; 95% confidence interval [CI] 2.18-2.68), study cohort, and three body composition profiles characterized by myosteatosis combined with either sarcopenia (IRR, 1.27; 95% CI 1.12-1.43) or VO (IRR, 1.25; 95% CI 1.10-1.42), and myosteatosis combined with both sarcopenia and VO (IRR, 1.58; 95% CI 1.29-1.93). In the multivariable analysis, risk of readmission was associated with VO alone (odds ratio [OR] 2.66; 95% CI 1.18-6.00); P = 0.018), VO combined with myosteatosis (OR, 2.72; 95% CI 1.36-5.46; P = 0.005), or VO combined with myosteatosis and sarcopenia (OR, 2.98; 95% CI 1.06-5.46; P = 0.038). Importantly, the effect of body composition profiles on LOS and readmission was independent of major complications.

CONCLUSION

The findings showed that CT-defined multidimensional body habitus is independently associated with LOS and hospital readmission.

The prevalence of sarcopaenia in a vascular surgical patient cohort and its impact on outcome

BACKGROUND

Sarcopaenia, loss of lean muscle mass and quality, has prognostic significance and can be used to guide the management of oncology patients.¹ However, there is limited research into the prevalence and effect of sarcopaenia in vascular populations. We aim to investigate the prevalence of this measure of physiological reserve in a vascular patient group.

METHODS

All patients admitted to a tertiary vascular unit in a single year were considered for the study. Patients with an abdominal CT scan (available for analysis) within 12 months of admission were included. Patient data were extracted from electronic patient records and hospital case notes. CT scans were analysed at L3 vertebral body to calculate body composition indices, as previously described.¹ Sarcopaenia was defined as skeletal muscle index of <41 cm²/m² in female patients and non-obese males and <53 cm²/m² in obese males. Outcome at 3-years was ascertained.

RESULTS

Of 314 patients, 129 (41.1%) were sarcopaenic. Female patients were more likely to be sarcopaenic (p < 0.0001). The prevalence of sarcopaenia increased with age (p < 0.001). Rates of sarcopaenia didn't differ between occlusive and aneurysmal diagnoses. In a potentially unique finding in vascular literature to date, mortality and non-home discharge were not significantly different between the groups. On multivariate analysis, sarcopaenia was not significantly associated with earlier death (p = 0.55).

CONCLUSIONS

Sarcopaenia is highly prevalent in vascular surgical patients. In our analysis, sarcopaenia was not independently associated with mortality. Potentially the associated cardiovascular risk of patients with end stage vascular disease may negate the additional risk of altered body composition.

Diagnostic Criteria and Clinical Outcomes in Sarcopenia Research: A Literature Review

By the sixth decade of life, nearly one quarter of the population has substantial muscle atrophy, or sarcopenia. Despite the creation of a standardized definition of sarcopenia by the European Working Group on Sarcopenia in Older People, variability may exist in the diagnostic criteria utilized for clinical sarcopenia research. The primary objectives of this review were to characterize diagnostic criteria used for measurement of sarcopenia in original studies, and to describe associations between sarcopenia and important clinical outcomes. We performed a literature review of the term “sarcopenia” in PubMed. Inclusion criteria were English language, original data, a clear and specific definition for diagnosing sarcopenia, and the analysis of sarcopenia’s effect on a clinical outcome. A total of 283 studies met inclusion criteria. More than half of the included sarcopenia investigations were level IV studies (54.1%), while 43.1% provided level II evidence. Under one third (27.6%) of studies examined sarcopenia with regard to surgical outcomes. In terms of diagnostic criteria for sarcopenia, 264 (93.3%) studies used measures of skeletal muscle mass, with dual energy X-ray absorptiometry (DEXA) being the most common modality (43.6%). Sarcopenia was found to be a consistent predictor of chronic disease progression, all-cause mortality, poorer functional outcomes, and postoperative complications. In conclusion, there is substantial evidence that sarcopenia impacts both medical and surgical outcomes. However, current research has utilized heterogeneous diagnostic criteria for sarcopenia. Further efforts to standardize the modalities used to diagnose sarcopenia in clinical research and practice will help strengthen our ability to study this important phenomenon.

Morphometric Assessment as a Predictor of Outcome in Older Vascular Surgery Patients

BACKGROUND

Frailty is a recognized predictor of poor outcome in patients undergoing surgical intervention. Frailty is intricately linked with body morphology, which can be evaluated using morphometric assessment via computerized tomographic (CT) imaging. We aimed to assess the predictive power of such objective assessments in a broad cohort of vascular surgical patients.

METHODS

A consecutive series of patients aged over 65 years admitted to a vascular unit, who had undergone CT imaging of the abdomen, were analyzed. Demographic and patient-specific data were collated alongside admission relevant information. Outcomes included mortality, length of stay, health care-related costs, and discharge destination. Images were analyzed for 4 morphometric measurements: (1) psoas muscle area, (2) mean psoas density, (3) subcutaneous fat depth, and (4) intra-abdominal fat depth, all taken at the level of the fourth lumbar vertebra.

RESULTS

Two hundred and ten patients were initially analyzed. Forty-four patients had significant retroperitoneal and abdominal abnormalities that limited appropriate CT analysis. Decreased subcutaneous fat depth was significantly associated with mortality, readmission within 12 months, and increased cost of health care (P < 0.01, adjusted for confounders). Psoas muscle area was significantly associated with readmission-free survival.

CONCLUSIONS

Morphometric analysis predicts poorer outcome in a broad cohort of vascular surgery patients. Such assessment is likely to enhance patient counseling regarding individual risk as well as enhancing the ability to undertake risk-modified surgical audit.

Early nutritional inadequacy is associated with psoas muscle deterioration and worse clinical outcomes in critically ill surgical patients

PURPOSE

To explore whether psoas cross sectional area (CSA) and density (Hounsfield Units, HU) are associated with nutritional adequacy and clinical outcomes in surgical intensive care unit patients.

MATERIALS AND METHODS

Subjects with at least one CT scan within 72h of ICU admission were included. Demographic, nutritional, radiographic, and outcomes data were collected. Psoas muscle CSA and HU were assessed at the L4-L5 intervertebral disk level. Change (Δ) in CSA and HU overall and per day were calculated.

RESULTS

140 patients were included. There was no significant correlation between baseline CSA and HU and clinical outcomes. Patients with at least two CT scans (n=65), had a median decrease in CSA of -15% [IQR: -20%, -8%] and decrease in HU of -2% [IQR: -30%, +24%]. Patients with the greatest daily %HU decline received significantly fewer calories/kg and proteins/kg and accumulated greater protein deficits at day 7 and overall. Patients with daily %HU increase had the shortest ICU and hospital LOS and more ventilator-free days in univariate and multivariable analyses.

CONCLUSIONS

In this exploratory study, early nutritional deficits were correlated with muscle quality deterioration. Inpatient gain in psoas density, compared to maintenance or loss, is associated with shorter hospital stay.

Muscle, Health and Costs: A Glance at their Relationship

OBJECTIVE

To assess the association between muscle parameters (mass, strength, physical performance) and activities of daily living (ADL), quality of life (QoL), and health care costs.

DESIGN

Cross-sectional Maastricht Sarcopenia Study (MaSS).

SETTING

Community-dwelling, assisted-living, residential living facility.

PARTICIPANTS

227 adults aged 65 and older.

MEASUREMENTS

Muscle mass, hand grip strength and physical performance were assessed by bio-electrical impedance, JAMAR dynamometer and the Short Physical Performance Battery, respectively. Health outcomes were measured by the Groningen Activity Restriction Scale (disability in ADL) and the EQ-5D-5L (QoL). Health care costs were calculated based on health care use in the past three months.

RESULTS

Muscle strength and physical performance showed a strong correlation with ADL, QoL, and health care costs (P<.01); for muscle mass no significant correlations were observed. Regression analyses showed that higher gait speed (OR 0.06, 95%CI 0.01-0.55) was associated with a lower probability of ADL disability. Furthermore, slower chair stand (OR 1.23, 95%CI 1.08-1.42), and more comorbidities (OR 1.58, 95%CI 1.23-2.02) were explanatory factors for higher ADL disability. Explanatory factors for QoL and costs were: more disability in ADL (OR 1.26, 95%CI 1.12-1.41 for QoL; B = 0.09, P<.01 for costs) and more comorbidities (OR 1.44, 95%CI 1.14-1.82 for QoL; B = 0.35, P<.01 for costs).

CONCLUSION

Lower gait speed and chair stand were potential drivers of disability in ADL. Disability in ADL and comorbidities were associated with QoL and health care costs in community-dwelling older adults. Improving physical performance may be a valuable target for future intervention and research to impact health burden and costs.

Inpatient costs and blood transfusion rates of sarcopenic patients following thoracolumbar spine surgery

OBJECTIVE

Sarcopenia, the muscle atrophy associated with aging and disease progression, accounts for nearly $18.5 billion in health care expenditures annually. Given the high prevalence of sarcopenia in patients undergoing orthopedic surgery, the goal of this study was to assess the impact of sarcopenia on inpatient costs following thoracolumbar spine surgery.

METHODS

Patients older than 55 years undergoing thoracolumbar spine surgery from 2003 to 2015 were retrospectively analyzed. Sarcopenia was measured using total psoas area at the L-4 vertebra on perioperative CT scans. Hospital billing data were used to compare inpatient costs, transfusion rate, and rate of advanced imaging utilization.

RESULTS

Of the 50 patients assessed, 16 were sarcopenic. Mean total hospital costs were 1.75-fold greater for sarcopenic patients compared with nonsarcopenic patients ($53,128 vs $30,292, p = 0.04). Sarcopenic patients were 2.1 times as likely to require a blood transfusion (43.8% vs 20.6%, p = 0.04). Sarcopenic patients had a 2.6-fold greater usage of advanced imaging (68.8% vs 26.5%, p = 0.002) with associated higher diagnostic imaging costs ($2452 vs $801, p = 0.01). Sarcopenic patients also had greater pharmacy, laboratory, respiratory care, and emergency department costs.

CONCLUSIONS

This study is the first to show that sarcopenia is associated with higher postoperative costs and rates of blood transfusion following thoracolumbar spine surgery. Measuring the psoas area may represent a strategy for predicting perioperative costs in spine surgery patients.

Low skeletal muscle mass is associated with increased hospital expenditure in patients undergoing cancer surgery of the alimentary tract

BACKGROUND

Low skeletal muscle mass is associated with poor postoperative outcomes in cancer patients. Furthermore, it is associated with increased healthcare costs in the United States. We investigated its effect on hospital expenditure in a Western-European healthcare system, with universal access.

METHODS

Skeletal muscle mass (assessed on CT) and costs were obtained for patients who underwent curative-intent abdominal cancer surgery. Low skeletal muscle mass was defined based on pre-established cut-offs. The relationship between low skeletal muscle mass and hospital costs was assessed using linear regression analysis and Mann-Whitney U-tests.

RESULTS

452 patients were included (median age 65, 61.5% males). Patients underwent surgery for colorectal cancer (38.9%), colorectal liver metastases (27.4%), primary liver tumours (23.2%), and pancreatic/periampullary cancer (10.4%). In total, 45.6% had sarcopenia. Median costs were €2,183 higher in patients with low compared with patients with high skeletal muscle mass (€17,144 versus €14,961; P<0.001). Hospital costs incrementally increased with lower sex-specific skeletal muscle mass quartiles (P = 0.029). After adjustment for confounders, low skeletal muscle mass was associated with a cost increase of €4,061 (P = 0.015).

CONCLUSION

Low skeletal muscle mass was independently associated with increased hospital costs of about €4,000 per patient. Strategies to reduce skeletal muscle wasting could reduce hospital costs in an era of incremental healthcare costs and an increasingly ageing population.

Sarcopaenia in surgical populations: A review

Sarcopaenia, or decreased muscle mass, has been the subject of a large quantity of recent literature in both medical and surgical disciplines. It has been shown, as outlined below, to be of great prognostic importance, and also may be used in certain circumstances to guide treatment. The greatest volume of research into this topic is in oncological surgical populations, in whom the prevalence of sarcopaenia has been shown to be high. However it is being increasingly studied in other patient groups. Interest in using sarcopaenia as an objective and potentially modifiable marker of frailty is increasing, especially with regards to pre-operative risk stratification and amelioration. In this review we consider the current literature regarding the cause and effect of sarcopaenia, the methods by which it may be identified and the potential ways in which it may be treated, in the interest of improving outcomes for surgical patients.

Psoas Muscle Area as a Predictor of Outcomes in Transcatheter Aortic Valve Implantation

Frailty is a powerful predictor of outcomes after transcatheter aortic valve implantation (TAVI). Sarcopenia as assessed by psoas muscle area (PMA) is a validated tool to assess frailty before surgical procedures. We evaluated PMA as a predictor of outcomes after TAVI in 152 consecutive patients who underwent this procedure at our institution from 2011 to 2014. Preoperative computed tomography scans were used to measure PMA, which then was indexed to body surface area. Outcomes evaluated included (1) early poor outcome (30 days mortality, stroke, dialysis, and prolonged ventilation), (2) 1-year mortality, and (3) high-resource utilization (length of stay >7 days, discharge to rehabilitation, or readmission within 30 days). Indexed PMA (odds ratio [OR] 3.19, confidence interval [CI] 1.30 to 7.83; p = 0.012) and age (OR 1.92, CI 1.87 to 1.98; p = 0.012) predicted early poor outcome. Society of Thoracic Surgeons score predicted 1-year mortality (hazard ratio 3.07, CI 1.93 to 6.23; p = 0.011). High-resource utilization was observed more frequently in patients with PMA less than the median (73% vs 51%, OR 2.65, CI 1.32 to 5.36; p = 0.006). In conclusion, indexed PMA predicts early poor outcome and high-resource utilization after TAVI.

Computed tomography abbreviated assessment of sarcopenia following trauma: The CAAST measurement predicts 6-month mortality in older adult trauma patients

BACKGROUND

Older adult trauma patients are at increased risk of poor outcome, both immediately after injury and beyond hospital discharge. Identifying patients early in the hospital stay who are at increased risk of death after discharge can be challenging.

METHODS

Retrospective analysis was performed using our trauma registry linked with the social security death index from 2010 to 2014. Age was categorized as 18 to 64 and 65 years or older. We calculated mortality rates by age category then selected elderly patients with mechanism of injury being a fall for further analysis. Computed Tomography Abbreviated Assessment of Sarcopenia for Trauma (CAAST) was obtained by measuring psoas muscle cross-sectional area adjusted for height and weight. Kaplan-Meier survival analysis was performed, and proportional hazards regression modeling was used to determine independent risk factors for in-hospital and out-of-hospital mortality.

RESULTS

A total of 23,622 patients were analyzed (16,748, aged 18-64 years; and 6,874, aged 65 or older). In-hospital mortality was 1.96% for ages 18 to 64 and 7.19% for age 65 or older (p < 0.001); postdischarge 6-month mortality was 1.1% for ages 18 to 64 and 12.86% for age 65 or older (p < 0.001). Predictors of in-hospital and postdischarge mortality for ages 18 to 64 and in-hospital mortality for ages 65 or older group included injury characteristics such as ISS, admission vitals, and head injury. Predictors of postdischarge mortality for age 65or older included skilled nursing before admission, disposition, and mechanism of injury being a fall. A total of 57.5% (n = 256) of older patients who sustained a fall met criteria for sarcopenia. Sarcopenia was the strongest predictor of out-of-hospital mortality in this cohort with a hazard ratio of 4.77 (95% confidence interval, 2.71-8.40; p < 0.001).

CONCLUSION

Out of hospital does not assure out of danger for the elderly. Sarcopenia is a strong predictor of 6-month postdischarge mortality for older adults. The CAAST measurement is an efficient and inexpensive measure that can allow clinicians to target older trauma patients at risk of poor outcome for early intervention and/or palliative care services.

LEVEL OF EVIDENCE

Prognostic and epidemiologic study, level III.

Influence of IV Contrast Administration on CT Measures of Muscle and Bone Attenuation: Implications for Sarcopenia and Osteoporosis Evaluation

OBJECTIVE

The objective of our study was to characterize enhancement of muscle and bone that occurs on standardized four-phase contrast-enhanced CT.

MATERIALS AND METHODS

Two musculoskeletal radiologists reviewed standardized four-phase abdominal CT scans obtained with IV contrast material. The psoas area was measured, and the mean attenuation (in Hounsfield units) was recorded for the aorta, psoas muscles, posterior paraspinal muscles, and L4 vertebral body. CT attenuation measures were compared between anatomic regions and imaging phases with the paired t test; associations between measures were examined with the Pearson correlation coefficient (R).

RESULTS

The study included 201 patients (97 men, 104 women; mean age, 57.7 ± 12.5 [SD] years). Subject age was inversely correlated with unenhanced attenuation in the psoas muscles, posterior paraspinal muscles, and L4 (p < 0.001). The psoas muscles, posterior paraspinal muscles, and L4 enhanced significantly (p < 0.001) at all three contrast-enhanced phases. The greatest muscle enhancement was observed on delayed phase scans, whereas the greatest enhancement in L4 was seen on portal phase imaging. The unenhanced attenuation of the psoas muscles was significantly and negatively correlated with enhancement of the psoas muscles at the portal and delayed phases (p < 0.05 and p < 0.01, respectively), but these correlations were not seen for the posterior paraspinal muscles. Age was positively correlated with posterior paraspinal muscle enhancement at the portal and delayed phases in men (p < 0.05 and p < 0.01, respectively) but not in women.

CONCLUSION

Contrast enhancement of commonly measured muscle and bone regions is routinely observed and should be considered when using CT attenuation values as biomarkers of sarcopenia and osteoporosis. Furthermore, CT enhancement may be significantly influenced by age, sex, and unenhanced tissue attenuation.

Bone mineral density predicts posttransplant survival among hepatocellular carcinoma liver transplant recipients

Hepatocellular carcinoma (HCC) is a common indication for liver transplantation (LT). Recent data suggest that body composition features strongly affect post-LT mortality. We examined the impact of body composition on post-LT mortality in patients with HCC. Data on adult LT recipients who received Model for End-Stage Liver Disease exception for HCC between February 29, 2002, and December 31, 2013, and who had a computed tomography (CT) scan any time 6 months prior to LT were reviewed (n = 118). All available CT scan Digital Imaging and Communication in Medicine files were analyzed using a semiautomated high throughput methodology with algorithms programmed in MATLAB. Analytic morphomics measurements including dorsal muscle group (DMG) area, visceral and subcutaneous fat, and bone mineral density (BMD) were taken at the bottom of the eleventh thoracic vertebral level. Thirty-two (27%) patients died during the median follow-up of 4.4 years. The number of HCC lesions (hazard ratio [HR], 2.81; P < 0.001), BMD (HR = 0.90/Hounsfield units [HU]; P = 0.03), pre-LT locoregional therapy (HR = 0.14; P < 0.001), and donor age (HR = 1.05; P < 0.001) were the independent predictors of post-LT mortality. DMG area did not affect post-LT survival. In conclusion, in addition to number of HCC lesions and pre-LT locoregional therapy, low BMD, a surrogate for bone loss rather than DMG area, was independently associated with post-LT mortality in HCC patients. Bone loss may be an early marker of deconditioning that precedes sarcopenia and may affect transplant outcomes. Liver Transplantation 22 1092-1098 2016 AASLD.