GFR Variability, Survival, and Cardiovascular Events in Older Adults

Rationale & Objective: Variability in estimated glomerular filtration rate (eGFR) over time is often observed, but it is unknown whether this variation clinically important. We investigated the associa-tion between eGFR variability and survival free of dementia or persistent physical disability (dis ability-free survival) and cardiovascular disease (CVD) events (myocardial infarction, stroke, hospit aliza-tion for heart failure, or CVD death).Study Design: Post hoc analysis.Setting & Participants: 12,549 participants of the ASPirin in Reducing Events in the Elderly trial. Participants were without documented dementia, major physical disability, previous CVD, and major life-limiting illness at enrollment. Predictors: eGFR variability. Outcomes: Dis ability-free survival and CVD events.Analytical Approach: eGFR variability was esti-mated using the standard deviation of eGFR measurements obtained from participants' base-line, first, and second annual visits. Associations between tertiles of eGFR variability with disability-free survival and CVD events occurring after the eGFR variability estimation period were examined.Results: During median follow-up of 2.7 years after the second annual visit, 838 participants died, developed dementia, or acquired a persistent physical disability; 379 had a CVD event. The highest tertile of eGFR variability had an increased risk of death/dementia/disability (HR, 1.35; 95% CI, 1.14-1.5 9) and CVD events (HR, 1.37; 95% CI, 1.06-1.77) compared with the lowest tertile after covariate adjustment. These associations were present in patients with and without chronic kidney disease at baseline. Limitations: Limited representation of diverse demographics.Conclusions: In older, generally healthy adults, higher variability in eGFR over time predicts increased risk of future death/dementia/disability and CVD events.