Poor muscle quality as a predictor of high mortality independent of diabetes in hemodialysis patients

Abstract

Background: Poor muscle quality provides a clinically relevant measure for mortality in general population, particularly in the elderly people. Our previous reports indicating poorer muscle quality in diabetes mellitus (DM) hemodialysis patients than in non-DM counterparts prompted us to examine the association between two parameters in hemodialysis patients, independent of DM prevalence.

Methods: The study was performed from 1997 to 2005. Grip dynamometry and dual-energy X-ray absorptiometry (DXA) were used to measure handgrip strength (HGS) and arm lean mass (ALM), respectively, with the muscle quality defined as the ratio of HGS to ALM.

Results: During the mean follow-up period of 77 months, 90 out of 272 patients died. The patients were divided into higher and lower groups based on the values of muscle quality. In Kaplan-Meier analysis, the higher group revealed lower mortality than the lower group. Cox regression hazards analysis identified higher muscle quality as a significant independent predictor for better survival in hemodialysis patients (HR; 0.889, 95% CI 0.814-0.971; P<0.05), after adjustment for age, sex and the prevalence of DM. Since DM prevalence is a major factor for poorer muscle quality, another analysis was performed after restriction of the subjects to non-DM patients. The result also indicated that muscle quality provides a relevant measure independent of the presence of DM to predict the mortality in hemodialysis patients (HR; 0.849, 95% CI 0.759-0.950; P<0.05).

Conclusion: The study suggested that muscle quality provides a good marker for survival in hemodialysis patients, independently of the presence DM, age and serum albumin.