Body size, dose of hemodialysis, and mortality

This study investigates the role of body size on the mortality risk associa ted with dialysis dose in chronic hemodialysis patients, A national US rand om sample from the US Renal Data System was used for this observational lon gitudinal study of 2-year mortality. Prevalent hemodialysis patients treate d between 1990 and 1995 were included (n = 9,165), A Cox proportional hazar ds model, adjusting for patient characteristics, was used to calculate the relative risk (RR) for mortality. Both dialysis dose (equilibrated Kt/V [eK t/V]) and body size (body weight, body volume, and body mass index) were in dependently and significantly (P < 0.01 for each measure) inversely related to mortality when adjusted for age and diabetes. Mortality was less among larger patients and those receiving greater eKt/V. The overall association of mortality risk with eKt/V was negative and significant in all patient su bgroups defined by body size and by race-sex categories in the range 0.6 < eKt/V < 1.6. The association was negative in the restricted range 0.9 < eKt /V < 1.6 (although not generally significant) for all body-size subgroups a nd for three of four race-by-sex subgroups, excepting black men (RR = 1.003 /0.1 eKt/V; P > 0.95), These findings suggest that dose of dialysis and sev eral measures of body size are important and independent correlates of mort ality, These results suggest that patient management protocols should attem pt to ensure both good patient nutrition and adequate dose of dialysis, in addition to managing coexisting medical conditions. (C) 2000 by the Nationa l Kidney Foundation, Inc.