Predictors of quality of life among patients on dialysis in southern Brazil

CONTEXT AND OBJECTIVE: Quality of life (QoL) is considered important as an outcome measurement, especially for long-term diseases such as chronic renal failure. The present study searched for predictors of QoL in a sample of patients undergoing dialysis in southern Brazil. DESIGN AND SETTING: This was a cross-sectional study developed in three southern Brazilian dialysis facilities. METHODS: Health-related QoL of patients on hemodialysis or peritoneal dialysis was measured using the generic Short Form-36 (SF-36) health survey questionnaire. The results were correlated with sociodemographic, clinical and laboratory variables. The analysis was adjusted through multiple linear regression. RESULTS: A total of 140 patients were assessed: 94 on hemodialysis and 46 on peritoneal dialysis. The mean age was 54.2 ± 15.4 years, 48% were men and 76% were white. The predictors of higher (better) physical component summary in SF-36 were: younger age (β-0.16; 95% confidence interval, CI: -0.27 to -0.05), shorter time on dialysis (β-0.06; 95% CI: -0.09 to -0.02) and lower Khan comorbidity-age index (β 5.16; 95% CI: 1.7-8.6). The predictors of higher mental component summary were: being employed (β 8.4; 95% CI: 1.7-15.1), being married or having a marriage-like relationship (β 4.56; 95% CI: 0.9-8.2), being on peritoneal dialysis (β 4.9; 95% CI: 0.9-8.8) and not having high blood pressure (β 3.9; 95% CI: 0.3-7.6). CONCLUSIONS: Age, comorbidity and length of time on dialysis were the main predictors of physical QoL, whereas socioeconomic issues especially determined mental QoL