title: Association of dialyzer reuse with hospitalization and survival rates among U.S. hemodialysis patients: do comorbidities matter?
abstract: 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. This was a nonconcurrent cohort study 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. We found that reuse of dialyzers was associated with a similarly higher rate of death in analyses unadjusted for confounders (relative risk [RR] 1.25, 95% confidence interval [CI] 0.97-1.61), adjusted for demographics and renal diagnosis (RR 1.16, 95% CI 0.96-1.41), and analyses additionally adjusted for comorbidities (RR = 1.25, CI, 1.03, 1.52). Reusing dialyzers was also associated with a greater rate of hospitalization that was stable regardless of adjustment procedures. We 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 exists 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.
authors: Center for Clinical Epidemiology and Biostatistics and the Department of Biostatistics and Epidemiology, University of Pennsylvania Medical Center, University of Pennsylvania, Philadelphia 19104-6021, USA.
authors: H I
authors: HI
authors: Feldman
authors: W B
authors: WB
authors: Bilker
authors: M H
authors: MH
authors: Hackett
authors: C W
authors: CW
authors: Simmons
authors: J H
authors: JH
authors: Holmes
authors: M V
authors: MV
authors: Pauly
authors: J J
authors: JJ
authors: Escarce
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D015897:Comorbidity; D017743:Equipment Reuse; D005260:Female; D005500:Follow-Up Studies; D006331:Heart Diseases / Q000453:epidemiology; D006436:Hemodialysis Units, Hospital / Q000706:statistics & numerical data*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000453:epidemiology / Q000401:mortality / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology; D012044:Regression Analysis; D006435:Renal Dialysis / Q000295:instrumentation* / Q000401:mortality*; D016019:Survival Analysis; D014481:United States / Q000453:epidemiology