Effects of clinical and individual variables on quality of life in chronic renal failure patients

Background: The purpose of this study was to assess the effects of baseline characteristics of patients, chronic renal failure and its treatment on quality of life. Methods: To investigate the health status we used a questionnaire, the SF-36, during individual interviews. The study involved i) a cross-sectional observational stage, lasting from 1 Sept. 1997 to 30 April 1999, on all the patients undergoing conservative treatment, hemodialysis, peritoneal dialysis and kidney transplantation in district of Ravenna, and ii) a longitudinal stage, when the subjects were administered two questionnaires at an interval of at least 16 months. The quality of life data collected during the cross-sectional stage were analyzed to establish any correlations between age, type of treatment of chronic renal failure and hemoglobin levels. Patients under dialysis were also examined for any interference caused by the center where dialysis was done. Results: Multivariate analysis on the data collected during the cross-sectional stage showed that chronic renal failure treatment and age affected the quality of life scores for the following parameters: physical activity, bodily pain, general health and vitality (age was inversely related to the scores). Transplanted patients and those on conservative treatment enjoyed the best overall quality of life, followed by those on peritoneal dialysis and those on hemodialysis. The physical domain scores were strongly associated with age, hemoglobin and diabetes. Multivariate analysis of the longitudinal study indicated that the interval between the beginning and the end of the observation period, age and diabetes greatly influenced quality of life. Conclusions: The data confirmed that age and diabetes have a strong influence on the quality of life and that the long period of treatment, with the absence of any prospect of resolving the clinical situation, has a negative effect on the quality of life in uremic patients.