Relationship of body size and mortality among US Asians and Pacific Islanders on dialysis.

OBJECTIVES: The influence of body size on dialysis-related mortality among Asians and Pacific Islanders--heterogeneous ethnic groups with dissimilar body compositions--is poorly understood. Our study objective was to compare the relations of body size and mortality among patients with end-stage renal disease of different ethnicities. DESIGN, SETTING, AND PARTICIPANTS: We examined data from a cohort of 21,492 adult Asians, Pacific Islanders and non-Hispanic Whites who initiated dialysis during 1995-2003 within California, Hawaii and the US Pacific Islands. MAIN OUTCOME MEASURE: Time to death through September 22, 2008. RESULTS: Among both men and women, Pacific Islanders were the heaviest and Whites the tallest of the ethnic groups examined. Annual mortality rates were highest among Whites (29.6%), intermediate among Pacific Islanders (18.8%) and lowest among Asians (17.3%). Larger body size was associated with lower mortality among Pacific Islanders, Whites and most Asians on dialysis after adjustment for patient-level sociodemographic and clinical factors, area-based socioeconomic status and geographic clustering. Filipinos were the exception to this rule and showed a trend towards higher mortality with increasing body size. These findings were consistent irrespective of how body size was measured. CONCLUSIONS: Larger body size is associated with lower mortality among Pacific Islanders, Whites and most Asians on dialysis. Use of disaggregated ethnicity data may enhance our understanding of how ethnicity- or community-specific factors influence body size, body composition and dialysis-related outcomes in these diverse populations.