Sarcopenic obesity and its relation with muscle quality and mortality in patients on chronic hemodialysis

Myosteatosis is associated with adiposity, metabolic derangements and mortality in patients with chronic kidney disease

BACKGROUND/OBJECTIVES

Myosteatosis has been associated with sarcopenia, and increased mortality risk in patients on hemodialysis. We aimed to explore the associations between myosteatosis, as assessed by computed tomography (CT), with demographic parameters, body composition metrics, muscle strength, metabolic parameters and mortality in patients with chronic kidney disease (CKD).

SUBJECTS/METHODS

We enrolled 216 patients (age 60.3 ± 10.6 years, 63% men) with CKD stages 3-5. Abdominal CT scans at the third lumbar vertebra (L3) were used to assess body composition. Abdominal obesity was determined by abdominal adipose tissue (AT), sarcopenia by low skeletal muscle area (SMA) and low handgrip strength. Myosteatosis was evaluated by two parameters using CT scans at L3: mean muscle attenuation and percentage of intermuscular adipose tissue (%IMAT) within SMA. We evaluated the correlation between parameters of myosteatosis with demographic, clinical and metabolic variables. To determine independent predictors of myosteatosis, a multiple linear regression model was fitted. Mortality risk was evaluated with Cox-regression analysis.

RESULTS

Both parameters of myosteatosis were independently associated with age, metabolic syndrome, abdominal AT and SMA in the multiple linear regression analysis (adjusted R2 for multiple linear regression: muscle attenuation model 0.535, P < 0.001; %IMAT model 0.462, P < 0.001). Moreover, higher %IMAT and lower attenuation were associated with a higher mortality risk.

CONCLUSION

In patients with CKD, increased myosteatosis, as assessed by abdominal CT, was associated with old age, adiposity, metabolic dysfunction, and higher mortality risk.

Low Skeletal Muscle Density Assessed by Abdominal Computerized Tomography Predicts Outcome in Children With Chronic Kidney Disease

OBJECTIVES

Skeletal muscle loss and abnormal fat distribution are predictors of poor clinical outcomes in adults with chronic kidney disease (CKD). However, the relationship between body composition (muscle mass and adipose tissue) and prognosis in children with CKD has not been well elucidated.

METHODS

The retrospective single-center study enrolled children with CKD and healthy group who underwent an abdominal computerized tomography examination and compared the body composition of the third lumbar spine (L3) between the 2 groups. We defined the primary outcome as hemodialysis, peritoneal dialysis, kidney transplantation, or death. Logistic regression analysis was applied to assess the connection between low skeletal muscle density (SMD) and clinical and demographic variables. Multivariate Cox regression analysis was used to evaluate the risk factors for progression to the primary outcome. Kaplan-Meier survival analysis was performed to compare the effect of different body composition on event-free survival rate.

RESULTS

Thirty-two patients with CKD [estimated glomerular filtration rate: 14.89 (8.86, 29.88) (mL/min/1.73 m2)] and 66 heathy subjects [estimated glomerular filtration rate: 135.72 (121.70, 161.29) (mL/min/1.73 m2)] were recruited in our study. From the assessment of body composition assessed by computerized tomography, skeletal muscle area, SMD, and skeletal muscle index in the CKD group was lower than those in the healthy group (P < .05). On the other hand, visceral fat area and visceral fat index in the CKD group were significantly higher than those in the healthy group (P < .05). In logistic regression analysis, triglyceride (odds ratio: 8.635, 95% confidence interval (CI): 1.153-64.687) was independently associated with low SMD. After adjusting clinical data and body composition, high serum albumin (hazard ratio: 0.873, 95% CI: 0.798-0.955) and high SMD (hazard ratio: 0.895, 95% CI: 0.822-0.974) were protective factors for delaying renal failure. Based on the Kaplan-Meier analysis, only the group with low SMD had lower event-free survival in comparison to the reference group (P < .05).

CONCLUSIONS

These findings suggest that there is significant skeletal muscle loss and decrease in SMD in CKD children. Notably, low SMD is indicative of poor prognosis in CKD children.

Selective peroxisome proliferator-activated receptor-α modulator improves hypertriglyceridemia and muscle quality in patients with chronic kidney disease: A retrospective observational study

BACKGROUND & AIMS

Patients with chronic kidney disease (CKD) often have additional health problems, including sarcopenia and sarcopenic obesity. These conditions involve ectopic fat accumulation within muscles. This ectopic fat deposition reduces muscle quality, leading to weaker muscle strength and poorer physical performance. Persistent hypertriglyceridemia contributes to ectopic fat accumulation. Metabolic abnormalities, including dyslipidemia, are major factors in CKD development. Triglycerides (TG) and muscle quality are thus important factors in CKD management. Recently developed selective peroxisome proliferator-activated receptor α modulator (SPPARMα) hold promises for improving hypertriglyceridemia. However, their effectiveness and impact on muscle quality in CKD patients remain unclear. This study aimed to evaluate the effect of SPPARMα on muscle quality and its efficacy in CKD patients.

METHODS

This retrospective observational study involved CKD patients with dyslipidemia. We included patients who initiated medications for hypertriglyceridemia. We compared changes in lipid profiles, renal function, and muscle quality, assessed by phase angle, over six months between two groups: those receiving this type of medication and those receiving conventional treatment.

RESULTS

Among 245 patients diagnosed with CKD and hypertriglyceridemia, 52 started medications for hypertriglyceridemia. Of these, 26 received SPPARMα, and 26 received conventional lipid-lowering medications (statins, ezetimibe, eicosapentaenoic acid, and fibrates). SPPARMα significantly reduced TG (from 296.8 ± 106.1 to 153.0 ± 86.1, p < 0.001) without affecting glomerular filtration rate or urinary protein levels. Conventional treatment also improved TG (from 261.6 ± 89.5 to 173.6 ± 81.3, p < 0.001). Only patients treated with SPPARMα showed significant improvement in muscle quality. Their phase angle increased from 5.41 ± 0.6 to 5.55 ± 0.6 after six months of treatment (p < 0.05).

CONCLUSIONS

Our study demonstrates that the newly developed SPPARMα significantly lowers TG levels in CKD patients without harming their kidneys. Additionally, only patients treated with SPPARMα showed improvement in muscle quality. These findings suggest that SPPARMα may be a valuable treatment option for CKD patients with dyslipidemia, particularly those with low muscle quality.

Association of changes in body composition with all-cause mortality in patients undergoing hemodialysis: A prospective cohort study

OBJECTIVES

This study aimed to explore the effect of longitudinal body composition changes on mortality risk in patients undergoing hemodialysis and identify whether changes in body composition can more accurately predict mortality than baseline status.

METHODS

A prospective cohort study was conducted on 340 patients undergoing hemodialysis. Lean mass and body fat were determined using a bioimpedance spectroscopy (BIS) device and expressed as the lean tissue index (LTI) or fat tissue index (FTI), respectively. The patients were subjected to BIS at baseline and after 1 year. The hazard ratio (HR) for death was calculated using Cox regression analysis.

RESULTS

Among 340 patients, 289 were tested with a repeat BIS. LTI loss and FTI gain were observed in 51.2% and 47.1% of the patients, respectively. Low baseline LTI was a significant predictor of all-cause mortality after adjusting for demographic and biochemical parameters (HR, 2.41; P = 0.047), but not when comorbidities were included in the multivariate analysis. However, after adjusting for various confounding factors, LTI loss (HR, 3.40; P = 0.039) and FTI gain (HR, 4.06; P = 0.024) were independent risk factors for all-cause mortality, and the adjusted HR for LTI loss and FTI gain vs. no LTI loss and no FTI gain was 5.34 (P = 0.016).

CONCLUSIONS

LTI loss and FTI gain, particularly their combination, are important predictors of survival in patients undergoing hemodialysis. Our results emphasize that longitudinal changes in LTI and FTI are more strongly associated with all-cause mortality than single-point values. Therefore, it is important to dynamically assess the muscle and fat tissues and develop potential targeted treatment strategies for this population.

External validation of a novel nomogram for diagnosis of Protein Energy Wasting in adult hemodialysis patients

Background

Protein Energy Wasting (PEW) has high incidence in adult hemodialysis patients and refers to a state of decreased protein and energy substance. It has been demonstrated that PEW highly affects the quality of survival and increases the risk of death. Nevertheless, its diagnostic criteria are complex in clinic. To simplify the diagnosis method of PEW in adult hemodialysis patients, we previously established a novel clinical prediction model that was well-validated internally using bootstrapping. In this multicenter cross-sectional study, we aimed to externally validate this nomogram in a new cohort of adult hemodialysis patients.

Methods

The novel prediction model was built by combining four independent variables with part of the International Society of Renal Nutrition and Metabolism (ISRNM) diagnostic criteria including albumin, total cholesterol, and body mass index (BMI). We evaluated the performance of the new model using discrimination (Concordance Index), calibration plots, and Clinical Impact Curve to assess its predictive utility.

Results

From September 1st, 2022 to August 31st, 2023, 1,158 patients were screened in five medical centers in Shanghai. 622 (53.7%) hemodialysis patients were included for analysis. The PEW predictive model was acceptable discrimination with the area under the curve of 0.777 (95% CI 0.741-0.814). Additionally, the model revealed well-fitted calibration curves. The McNemar test showed the novel model had similar diagnostic efficacy with the gold standard diagnostic method (p > 0.05).

Conclusion

Our results from this cross-sectional external validation study further demonstrate that the novel model is a valid tool to identify PEW in adult hemodialysis patients effectively.

Sarcopenic Obesity and Outcomes for Patients With Cancer

Importance

The European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO) have recently proposed a consensus definition and diagnostic criteria for sarcopenic obesity (SO).

Objective

To implement the ESPEN-EASO diagnostic algorithm to investigate the prevalence of SO and its association with outcomes in patients with solid tumor cancers, with particular regard to associations among SO, overall survival (OS), and patient quality of life (QoL).

Design, Setting, and Participants

This prospective cohort study included patients diagnosed with solid tumor starting in May 7, 2013, with the last follow-up on June 30, 2022. Patients with solid tumors were categorized into SO and non-SO groups according to ESPEN-EASO criteria. The primary outcome was OS and the secondary outcomes included patient QoL and risk of intensive care unit (ICU) admission. Data were analyzed from June to December 2023.

Results

A total of 6790 patients were included in the study (mean [SD] age, 59.64 [10.77] years; 3489 were female [51.4%]). The prevalence of SO was 4.36% (296 of 6790) in the whole cohort and 14.98% (296 of 1976) in the subgroup with obesity. SO prevalence increased with age. During a median (IQR) follow-up period of 6.83 (5.67-7.04) years, 2103 patients died. Cox regression analysis indicated that SO was independently associated with lower OS (hazard ratio [HR], 1.54; 95% CI, 1.23-1.92), which was observed in both men (HR, 1.51; 95% CI, 1.09-2.10) and women (HR, 1.53; 95% CI, 1.12-2.07). SO was also associated with poorer QoL and higher risk of ICU admission (odds ratio, 2.39; 95% CI, 1.06-5.29). Among the diagnostic components of SO, low hand grip strength (HGS) was the only SO component associated with poor OS (HR, 1.15; 95% CI, 1.04-1.28).

Conclusions and Relevance

This cohort study of SO found that SO was significantly associated with lower OS, poorer QoL, and higher risk of ICU admission. Weak HGS, 1 of the diagnostic conditions, was the only component of SO associated with OS. The ESPEN-EASO algorithm appears to be an applicable tool to identify cancer-associated SO, which represents a major clinical complication and factor associated with risk for poor outcomes in these patients.

Prevalence and impact on the outcome of myosteatosis in patients with cirrhosis: a systematic review and meta-analysis

BACKGROUND

Myosteatosis in cirrhotic patients has been evaluated in limited studies with conflicting results and no systematic review or meta-analysis have been performed in this setting.

METHODS

We searched for all articles published until June 2023 to evaluate the prevalence of myosteatosis in cirrhosis and chronic liver disease.

RESULTS

Seventeen studies focused on cirrhosis and five studies in patients with chronic liver disease were included: the overall pooled prevalence of myosteatosis was 46% [95% Confidence Interval (CI) 36-57%] and 33% (95% CI 15-59%), respectively (p = 0.35). Among the studies with cirrhosis, the prevalence of myosteatosis was higher in those using the body mass index-based definition of myosteatosis (56%), than gender-based (36%) or other criteria (21%) (p < 0.01); was higher in women than in men (61% vs 45%), in Child-Pugh class C than A or B (57% vs 49% vs 50%), in non-alcoholic fatty liver disease (NAFLD)- than viral-associated cirrhosis (57% vs 43%), but these differences were not statistically significant (p > 0.05). Cirrhotic patients with myosteatosis, compared to those without myosteatosis, had more frequently a previous history of hepatic encephalopathy (32% vs 15%, p = 0.04), less frequently a previous history of variceal bleeding (46% vs 65%, p < 0.01), were more likely to suffer from diabetes mellitus (27% vs 18%, p < 0.01), while they had higher mortality rates (40% vs 14%, p = 0.02).

CONCLUSION

Myosteatosis is highly prevalent in patients with cirrhosis, particularly in those with NAFLD-associated cirrhosis. Myosteatosis is associated with hepatic encephalopathy, while it seems to have a negative impact on the outcome.

Making the invisible visible: imaging techniques for assessing muscle mass and muscle quality in chronic kidney disease

Muscle wasting and low muscle mass are prominent features of protein energy wasting (PEW), sarcopenia and sarcopenic obesity in patients with chronic kidney disease (CKD). In addition, muscle wasting is associated with low muscle strength, impaired muscle function and adverse clinical outcomes such as low quality of life, hospitalizations and increased mortality. While assessment of muscle mass is well justified, the assessment of skeletal muscle should go beyond quantity. Imaging techniques provide the means for non-invasive, comprehensive, in-depth assessment of the quality of the muscle such as the infiltration of ectopic fat. These techniques include computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound. Dual energy X-ray absorptiometry is also an imaging technique, but one that only provides quantitative and not qualitative data on muscle. The main advantage of imaging techniques compared with other methods such as bioelectrical impedance analysis and anthropometry is that they offer higher precision and accuracy. On the other hand, the higher cost for acquiring and maintaining the imaging equipment, especially CT and MRI, makes these less-used options and available mostly for research purposes. In the field of CKD and end-stage kidney disease (ESKD), imaging techniques are gaining attention for evaluating muscle quantity and more recently muscle fat infiltration. This review describes the potential of these techniques in CKD and ESKD settings for muscle assessment beyond that of muscle quantity.

Association between sarcopenic obesity and mortality in patients on peritoneal dialysis: a prospective cohort study

Background

Whether sarcopenic obesity had unfavorable effect on survival of peritoneal dialysis (PD) patients is unknown. We aimed to investigate the association between sarcopenic obesity and survival in PD patients.

Methods

This was a prospective observational study. Eligible PD patients from November 2016 to December 2017 were enrolled and followed until August 31, 2023. Sarcopenia was defined following the recommendations of the Asian Working Group for Sarcopenia (AWGS) as low appendicular skeletal muscle mass index (ASMI) and handgrip strength (HGS). Obesity was defined using the percentage of body fat (PBF). Survival analysis was conducted using the Kaplan-Meier and log-rank test. The Cox regression and the cumulative incidence competing risk (CICR) analyzes were used to investigate the association between sarcopenic obesity and all-cause mortality.

Results

A total of 223 patients were enrolled with 133 (59.6%) males, a median age of 57.5 (44.6, 65.7) years, a median dialysis vintage of 20.3 (6.4, 57.7) months and 48 (21.5%) who had comorbid diabetes mellitus. Among them, 46 (20.6%) patients were sarcopenic, and 25 (11.2%) patients were diagnosed with sarcopenic obesity. After followed up for 51.6 (25.6, 73.9) months, the Kaplan-Meier curve showed the sarcopenic obesity (log-rank = 13.527, p < 0.001) group had significant lower survival rate compared to the nonsarcopenic non-obesity group. For multivariate analysis, the CICR method showed patients with sarcopenic obesity had significantly higher mortality rate (HR: 2.190, 95% CI: 1.011-4.743, p = 0.047) compared to those with nonsarcopenic non-obesity.

Conclusion

Sarcopenia is not uncommon in PD patients, with a considerable proportion having sarcopenic obesity. There is a significant association between sarcopenic obesity and an increased risk of mortality in PD patients.

Clinical Significance of Nutritional Status, Inflammation, and Body Composition in Elderly Hemodialysis Patients-A Case-Control Study

Nutritional and inflammatory disorders are factors that increase the risk of adverse clinical outcomes and mortality in elderly hemodialysis (HD) patients. This study aimed to examine nutritional and inflammation status as well as body composition in older adults on HD compared to matched controls. A case-control study was conducted on 168 older participants (84 HD patients (cases) and 84 controls) age- and sex-matched. Demographic, clinical, anthropometric, and laboratory parameters were collected from medical records. The primary outcome was nutritional status assessment using a combination of nutritional and inflammatory markers along with the geriatric nutritional risk index (GNRI). Sarcopenic obesity (SO) was studied by the combined application of anthropometric measures. Body composition and hydration status were assessed by bioelectrical impedance analysis (BIA). Univariate and multivariate regression analyses were performed to identify nutritional and inflammatory independent risk indicators in elderly HD patients and controls. A significantly high prevalence of nutritional risk measured by the GNRI was found in HD patients (32.1%) compared to controls (6.0%) (p < 0.001). Elderly HD patients were overweight and had lower percent arm muscle circumference, phase angle (PA), serum albumin (s-albumin), as well as higher percent extracellular body water (ECW%) and serum C-reactive protein (s-CRP) than controls (all at least, p < 0.01). SO was higher in HD patients (15.50%) than in controls (14.30%). By multi-regression analyses, age < 75 years (OR: 0.119; 95%CI: 0.036 to 0.388), ECW% (OR: 1.162; 95%CI: 1.061 to 1.273), PA (OR: 0.099; 95%CI: 0.036 to 0.271), as well as BMI, s-albumin ≥ 3.8 g/dL, and lower s-CRP were independently related between cases and controls (all at least, p < 0.05). Elderly HD patients had increased nutritional risk, SO, inflammation, overhydration, and metabolic derangements compared to controls. This study highlights the importance of identifying nutritional risk along with inflammation profile and associated body composition disorders in the nutritional care of elderly HD patients. Further studies are needed to prevent nutritional disorders in elderly HD patients.