Muscle Mass Assessed by Computed Tomography at the Third Lumbar Vertebra Predicts Patient Survival in Chronic Kidney Disease

OBJECTIVE: Muscle mass is a key element for the evaluation of nutritional disturbances in patients with chronic kidney disease (CKD). Low muscle mass is associated with increased morbidity and mortality. The assessment of muscle mass by computed tomography at the third lumbar vertebra region (CTMM-L3) is an accurate method not subject to errors from fluctuation in the hydration status. Therefore, we aimed at investigating whether CTMM-L3 was able to predict mortality in nondialyzed CKD 3-5 patients. METHODS: This is a prospective observational cohort study. We evaluated 223 nondialyzed CKD patients (60.3 ± 10.6 years; 64% men; 50% diabetics; glomerular filtration rate 20.7 ± 9.6 mLmin1.73 m2). Muscle mass was measured by CTMM-L3 using the Slice-O-Matic software and analyzed according to percentile adjusted by gender. Nutritional parameters, laboratory data, and comorbidities were evaluated, and mortality was followed up for 4 years. RESULTS: During the study period, 63 patients died, and the main cause of death was cardiovascular disease. Patients who died were older, had lower hemoglobin and albumin, as well as lower muscle markers. CTMM-L3 below the 25th percentile was associated with higher mortality according to the Kaplan-Meier curve (P = .017) and in Cox regression analysis (crude hazard ratio, 1.87 [95% confidence interval, 1.11-3.16]), also when adjusting for potential confounders (hazard ratio 1.83 [95% confidence interval 1.02-3.30]). CONCLUSION: Low muscle mass measured by computed tomography at the third lumbar vertebra region is an independent predictor of increased mortality in nondialyzed CKD patients.

Muscle Mass Assessed by Computed Tomography at the Third Lumbar Vertebra Predicts Patient Survival in Chronic Kidney Disease.

OBJECTIVE: Muscle mass is a key element for the evaluation of nutritional disturbances in patients with chronic kidney disease (CKD). Low muscle mass is associated with increased morbidity and mortality. The assessment of muscle mass by computed tomography at the third lumbar vertebra region (CTMM-L3) is an accurate method not subject to errors from fluctuation in the hydration status. Therefore, we aimed at investigating whether CTMM-L3 was able to predict mortality in nondialyzed CKD 3-5 patients. METHODS: This is a prospective observational cohort study. We evaluated 223 nondialyzed CKD patients (60.3 ± 10.6 years; 64% men; 50% diabetics; glomerular filtration rate 20.7 ± 9.6 mLmin1.73 m2). Muscle mass was measured by CTMM-L3 using the Slice-O-Matic software and analyzed according to percentile adjusted by gender. Nutritional parameters, laboratory data, and comorbidities were evaluated, and mortality was followed up for 4 years. RESULTS: During the study period, 63 patients died, and the main cause of death was cardiovascular disease. Patients who died were older, had lower hemoglobin and albumin, as well as lower muscle markers. CTMM-L3 below the 25th percentile was associated with higher mortality according to the Kaplan-Meier curve (P = .017) and in Cox regression analysis (crude hazard ratio, 1.87 [95% confidence interval, 1.11-3.16]), also when adjusting for potential confounders (hazard ratio 1.83 [95% confidence interval 1.02-3.30]). CONCLUSION: Low muscle mass measured by computed tomography at the third lumbar vertebra region is an independent predictor of increased mortality in nondialyzed CKD patients.

Intramuscle fat infiltration in non-dialysis CKD: clinical determinants and association with mortality

BACKGROUND: Intramuscle fat infiltration (IFI) is an important feature of aging currently understood as a cause of muscle weakness in elderly. Compared to healthy controls, IFI has been reported elevated in chronic kidney disease (CKD) patients. Its determinants and consequences, however, are unknown. METHODS: Cross-sectional study with mortality follow-up of 195 nephrology-referred patients with non-dialysis CKD stages 3-5. Mean age was 60±11 years, 61% were men and glomerular filtration rate (creatinine clearance) was 25±12 ml/min/1.73 m2 . We used computed tomography (CT) scan (Slice-O-Matic software version 5.0) of the third lumbar vertebra to quantify the degree of IFI (reported as % of fat within muscle area). Muscles evaluated by CT were psoas, transversus abdominis, rectus abdominis, external and internal obliques, erector spinae and quadratus lumborum. Coronary artery calcification score (CAC) was evaluated by CT, muscle strength by dynamometry (handgrip strength, HGS) and shown as standard values to normative tables. RESULTS: IFI was higher in women than in men (9.7±6 vs 6.3±4%, P 0.05), and was positively correlated (Spearman test) with age (rho =0.37), Charlson comorbidity score (rho=0.19), CAC (r=0.16) and CT-derived visceral (rho=0.37) and subcutaneous fat (rho =0.57). IFI was negatively associated with HGS (rho=-0.25) and CT-derived skeletal muscle mass (rho=-0.37)...(AU)