Functional status and quality of life: predictors of early mortality among patients entering treatment for end stage renal disease

Abstract

We investigated the association between functional status and quality of life in newly-entered dialysis patients and the subsequent risk of mortality. We enrolled the patients from 37 dialysis facilities in two southeastern states (n = 294). Functional status was assessed by the Karnofsky Performance Scale (KPS) and quality of life by the Spitzer Quality of Life Index (SQLI). During a mean (SE) follow-up of 479.6 (109.4) days 49 patients (16.4%) of the cohort died. The mean KPS score (SE) for survivors was 7.31 (0.11) and for non-survivors was 5.89 (0.26), P less than 0.0001. The mean SQLI score (SE) for survivors was 6.74 (0.15) and non-survivors was 4.95 (0.28), P less than 0.0001. Strong gradients of the risk of mortality were found for both measurements. After controlling for other covariates including age, race, sex, primary cause of renal failure and the presence of comorbidity, both the KPS and SQLI scores were independently correlated with risk of mortality. We conclude that functional status and quality of life are strong independent risk factors for subsequent mortality in new dialysis patients. These are easily measured indicators which may serve to predict subsequent risk of mortality or adjust case-mix estimates for comparisons between dialysis populations.