Differences between anthropometric and bioimpedance measurements of muscle mass in the arm and hand grip and pinch strength in patients with chronic kidney disease.

Abstract

Chronic kidney disease (CKD) patients are at increased risk of sarcopenic muscle wasting, with increased mortality risk. Simple screening tests are required to detect sarcopenia to allow for interventional therapies. We wished to compare anthropometric and multifrequency bioimpedance (MFBIA) measurements of arm composition and muscle strength. We measured segmental MFBIA, mid arm upper circumference (MUAC) and triceps skin fold thickness (TSF), hand grip strength (HGS) and pinch strength (PS) in CKD patients attending out-patient review. We reviewed 146 patients; 94 male (64.4%), 93 (63.7%) diabetic, mean age 70.5±15 years, weight 77.6±17.1kg, with a mean HGS of 25.2±10.4, and PS 5.0±1.9kg. HGS and PS were correlated (r=0.63, p<0.001). Male patients had greater HGS and PS (28.3±10.1 vs 19.7±7.0kg; and 5.3±2.0 vs 4.3±1.1kg, p<0.05) with greater arm muscle (3.2±0.7 vs 2.4±0.7kg, p<0.05) and less arm fat (1.8±1.3 vs 2.9±1.8kg, p<0.05), whereas there was no difference in anthropometric measurements of mid upper arm muscle or fat area. Whereas both HGS and PS correlated positively with MFBIA arm lean mass (r=0.55, r=0.37, p<0.001) and negatively for arm fat mass (r=-0.4, p<0.001, r=-0.32, p=0.001) respectively, there were no correlations with anthropometric derived estimates of upper arm muscle or fat. In CKD patients, segmental MFBIA measurements of the arm, but not those derived from anthropometric measurements demonstrate gender differences and correlate with arm muscle strength, whereas there were no such correlations with anthropometric estimates of upper arm muscle or fat.