DIET, INDICATORS OF KIDNEY-DISEASE, AND LATER MORTALITY AMONG OLDER PERSONS IN THE NHANES-I EPIDEMIOLOGIC FOLLOW-UP-STUDY

Objectives. The purpose of this study was to determine whether diet ad versely affected survival among 2572 older persons with indicators of kidney disease in a population-based cohort. Average follow-up time fo r survivors, of whom 1453 (57%) had died at analysis, was 14.5 years. Methods. Kidney disease indicators were a ''yes'' response to ''Has a doctor ever told you that you have kidney disease or renal stones?'' a nd/or trace or greater amounts of protein in urine. Dietary protein in takes were calculated from 24-hour recalls. Results. Cox proportional hazards models were used, stratified by sex, with age, body mass index , blood pressure, education, smoking status, total caloric intake, and diabetes mellitus as covariates. Relative risk of total mortality wit h an additional 15 g of protein per day was 1.25 (95% confidence inter val [CI] = 1.09, 1.42) among White men with kidney disease indicators, vs 1.00 (95% CI = 0.95, 1.06) among those without them; relative risk s of renal-related mortality were 1.32 (95% CI = 0.97, 1.79) and 0.95 (95% CI = 0.81, 1.11), respectively. No significant differences were f ound for White women. Conclusions, Once chronic renal disease is prese nt, diet may be associated with earlier mortality in White males.