Association of Dialyzer Reuse with Hospitalization and Survival Rates Among U.S. Hemodialysis Patients
Do Comorbidities Matter?
Published in: Journal of Clinical Epidemiology, v. 52, no. 3, Mar. 1999, p. 209-217
Posted on RAND.org on December 31, 1998
The objective of this study was to determine whether the associations between reuse of hemodialyzers and higher rates of death and hospitalization persist after adjustment for comorbidity. The study was a nonconcurrent cohort analysis of survival and hospitalization rates among 1491 U.S. chronic hemodialysis patients beginning treatment in 1986 and 1987. The impact of dialyzer reuse was compared across three survival models: an unadjusted model, a base model adjusted only for demographics and renal diagnosis, and an augmented model additionally adjusted for comorbidities. The authors found that reuse of dialyzers was associated with a similarly higher rate of death in analyses unadjusted for confounders, adjusted for demographics and renal diagnosis, and adjusted for comorbidities. Reusing dialyzers was also associated with a greater rate of hospitalization that was stable regardless of adjustment procedures. They conclude that higher rates of death and hospitalization associated with dialyzer reuse persist regardless of adjustment for demographic characteristics or baseline comorbidities. These findings amplify concerns that there is elevated morbidity among hemodialysis patients treated in facilities that reuse hemodialyzers. Although the association we observed was not confounded by comorbidity, a cause-and-effect relationship between dialyzer reuse and morbidity could not be proved because of the inability to control for aspects of care other than dialyzer reuse.