A population-based cohort study defines prognoses in severe chronic kidney disease.

In older people with chronic kidney disease (CKD) and comorbidities, the risk of death or disability may overshadow the risk of kidney failure. To help refine this we did a retrospective population-based cohort study to evaluate the relative likelihood of adverse outcomes as functions of age and comorbidity burden among 47,228 adults with severe non-dialysis dependent CKD. We identified comorbidities using 29 validated algorithms applied to administrative data and assessed death, end-stage renal disease (ESRD), cardiovascular disease (CVD) events, and long-term care. Over five years of follow-up, 53.4% of participants died, 24.1% had a CVD event, 14.3% were placed into long-term care and 5.3% developed ESRD. Death was 145 times more likely and 11 times more likely than ESRD for participants aged 80 years or more and 60-79 years, respectively; long-term care was 30 times more likely and 1.7 times as likely as ESRD for participants aged 80 years or more and 60-79 years, respectively. Increasing comorbidity burden was similarly associated with increased risk of death and long-term care placement but reduced the likelihood of ESRD, and the risks of increasing age were similarly incremental. Thus, among patients with severe CKD, older age and/or higher comorbidity burden, death and long-term care placement are markedly more likely than ESRD. Hence, clinicians, patients and families should all consider the relative magnitude of these risks when making decisions about renal replacement.