Cross-sectional study of health-related quality of life in African Americans with chronic renal insufficiency: the African American Study of Kidney Disease and Hypertension Trial

Abstract

We measured health-related quality of life (HRQL) by using the Medical Outcomes Study 36-Item Short-Form (SF-36) in a cross-sectional study of 1,094 African American men and women with mild to moderate chronic renal insufficiency (mean glomerular filtration rate, 45.7 mL/min/1.73 m2) caused by hypertension before randomization onto the African American Study of Kidney Disease and Hypertension (AASK) Trial. Scales contributing to physical health and a summary measure, the Physical Component Summary (PCS) score (mean, 43.4 +/- 10.9 [SD]), were significantly lower than scales relating to mental health and the Mental Component Summary (MCS) score (51.3 +/- 10.3). All scales (except Role-Physical) and the PCS and MCS were significantly higher in men (44.3 +/- 10.9 and 51.8 +/- 10.0, respectively) than women (41.9 +/- 10.8 and 50.5 +/- 10.6, respectively). In multivariate analysis, employment status, education level, household income, body mass index, comorbid medical conditions, years of hypertension, number of antihypertensive drugs prescribed, exercise status, and male sex were significant independent predictors of PCS. Fewer factors predicted MCS and included employment status, marital status, current smoking, age, comorbid medical conditions, and male sex. In the entire AASK cohort, mean scores for individual scales, except Mental Health, and the PCS were lower, but the mean MCS score was slightly higher than values for the US general population. Values for individual scales of the SF-36 and the PCS were substantially higher among AASK participants compared with African-American hemodialysis patients. Six of the eight scales were lower in the AASK cohort compared with groups of racially mixed and exclusively African-American hypertensive subjects. We conclude that physical aspects of quality of life are substantially reduced compared with mental components among AASK participants, and a number of demographic and clinical characteristics significantly impact on HRQL.