Correlates and outcomes of dementia among dialysis patients: the Dialysis Outcomes and Practice Patterns Study

Background. Recent studies suggest a high prevalence of cognitive impairment and dementia in persons with end-stage renal disease (ESRD), yet risk factors for dementia and its prognostic significance in persons with ESRD remain unclear. The goals of this study were to determine the prevalence, correlates and dialysis-related outcomes of dementia in an international sample of haemodialysis patients. Methods. We analysed data collected from a cohort of 16 694 patients in the Dialysis Outcomes and Practice Patterns Study. Dementia was defined as a diagnosis of dementia documented in the medical record. We used logistic regression to determine the baseline correlates of dementia and Cox proportional hazards models to determine the relative risk (RR) of death and dialysis withdrawal for patients with dementia, while adjusting for a number of confounding factors. Results. Overall, 4% of the cohort had a recorded diagnosis of dementia. In the cross-sectional analyses, risk factors for dementia in the general population including age, black race, low educational attainment, cerebrovascular disease and diabetes, as well as modifiable uraemia-related factors, including markers of malnutrition and anaemia, were independently associated with dementia. After adjustment for a number of confounding factors, dementia was associated with an increased risk of death [RR 1.48, 95% confidence interval (CI) 1.32-1.66] and dialysis withdrawal (RR 2.01, 95% CI 1.57-2.57). Conclusions. Dementia is associated with adverse outcomes among ESRD patients. Dialysis providers should consider instituting routine screening for cognitive impairment among elderly patients in order to identify those at risk for associated adverse outcomes.