Prevalence and determinants of sarcopenia in Indian patients with chronic kidney disease stage 3 & 4

OBJECTIVES: There is limited literature on the prevalence and determinants of sarcopenia in the Indian predialysis chronic kidney disease (CKD) population. The current study attempts to characterize sarcopenia in CKD stages 3 & 4 using 3-compartment model dual-energy X-ray absorptiometry (DXA). METHODS: This is secondary data from a randomized trial on bicarbonate supplementation for preserving muscle mass. A 3-compartment DXA was done to assess body composition in 188 subjects aged 18 to 65, with stable kidney function. Sarcopenia was defined by Asian Working Group criteria - appendicular skeletal mass index < 5.4 kg/m(2) in women and < 7 kg/m(2) in men. RESULTS: Sarcopenia was present in 69.1% (n = 130). There was no difference in the prevalence of sarcopenia in CKD stage 3 (n = 62; 72.1%) vs CKD stage 4 (n = 68, 66.7%); P = 0.434. A lower body mass index (BMI) (OR 1.69; 95% CI 1.43, 2.01) and lower bicarbonate levels (OR 1.22; 95% CI 1.02, 1.47), and age (OR 0.95; 95% CI 0.91, 0.98) was independently associated with the muscle mass. A BMI cut-off of 18 failed to identify sarcopenia in 78.4% (n = 102) subjects (Kappa statistic 0.396). The receiver operating characteristic curve for mid-arm muscle circumference for identifying sarcopenia was 0.651 (95% CI 0.561, 0.740). CONCLUSIONS: Sarcopenia is highly prevalent in CKD 3 and 4. Sarcopenic individuals are older, with a low BMI and lower bicarbonate levels. The anthropometric parameters and biochemical parameters did not help identify sarcopenia in the predialysis population.