Changes in Anthropometry and Mortality in Maintenance Hemodialysis Patients in the HEMO Study

Background: Poor nutritional status has been associated with worse patient survival in maintenance hemodialysis patients. Anthropometric values are important nutritional measures, incorporating muscle and fat mass. However, the association of changes in anthropometry, including midarm circumference (MAC) and skinfold measurements, with mortality in hemodialysis patients remains unknown. Accordingly, we explored this association in the Hemodialysis (HEMO) Study. Study Design: Post hoc analysis of cohort data from a clinical trial. Setting & Participants: 1,846 hemodialysis patients enrolled in the HEMO Study. Predictors: MAC and skinfold measurements. Outcomes: Longitudinal changes in MAC and skinfolds were jointly modeled using repeated measures and survival modeling. Time-to-event outcomes were all-cause mortality, cardiac death and hospitalization, and infection-related death. Results: Mean MAC was 30.1 cm, and mean baseline sum of subscapular, biceps, and triceps skinfolds was 42.4 mm. During a median follow-up of 2.5 years, there were 845 deaths. During follow-up, MAC and the skinfold measurement declined 0.26 cm and 1.1 mm per year, respectively. Declines in MAC (per cm) and skinfold (per mm) measurements were associated with higher all-cause mortality (HRs of 1.58 [95% CI, 1.29-1.94; P < 0.001] and 1.06 [95% CI, 0.99-1.13; P = 0.09], respectively), poorer cardiac outcomes (HRs of 1.49 [95% CI, 1.23-1.81; P < 0.001] and 1.05 [95% CI, 0.99-1.10; P = 0.09], respectively), and higher infection-related hospitalization (HRs of 2.45 [95% CI, 1.55-3.88; P < 0.001] and 1.16 [95% CI, 0.98-1.37; P = 0.08], respectively). The association between declining MAC and skinfold with patient survival was most notable for those with body mass index (BMI) <= 25 kg/m(2) (HRs of 2.41 [95% CI, 1.81-3.19; P < 0.001] and 1.22 [95% CI, 1.10-1.35; P < 0.001], respectively). Limitations: Prevalent dialysis patients only, excluding individuals weighing >85 kg. Conclusions: Declines in skinfold thickness were not associated significantly with outcomes except for participants with BMI <25 kg/m(2). Declines in MAC are associated significantly with all-cause mortality and cardiac outcomes in hemodialysis patients, most notably in those with BMI <= 25 kg/m(2). (C) 2013 by the National Kidney Foundation, Inc.