Abstract WP208: Albuminuria, But Not eGFR, Predicts Stroke Risk In Patients With Chronic Kidney Disease
Background and Objectives: Chronic kidney disease (CKD) is associated with cardiovascular morbidity and mortality independent of common vascular risk factors. The Chronic Renal Insufficiency Cohort (CRIC) study is a large, multicenter, longitudinal study of patients with CKD. Using this cohort, we aimed to better understand how CKD influences stroke risk. We hypothesized that worsened renal function would be associated with an increased risk of stroke and that this would be independent of other vascular risk factors.
Methods: Baseline measures of renal function were collected 3 months after an initial screening visit for each CRIC participant who were then contacted every 6 months to identify possible stroke events. Medical records were reviewed by 2 independent vascular neurologists. Univariate and multivariate Cox proportional hazards regression analysis was performed to identify risk factors for future stroke events in patients with CKD. The study had 80% power to detect a hazard ratio (HR) of 1.87 for a 50% prevalent binary predictor.
Results: Among 3939 subjects followed for a median of 4.0 years, there were 101 stroke events. Decreased estimated glomerular filtration rate (eGFR), a common marker of renal dysfunction, was not associated with a risk of stroke (eGFR 30-60 mL/min/m2: HR 1.3 (95%CI 0.6-2.7); 15-29 mL/min/m2: HR 1.08 (0.5-2.5), <15 mL/min/m2: no stroke events occurred). Albuminuria >30 mg/day, another marker of kidney dysfunction, was associated with an increased risk of stroke. As albuminuria worsened, the risk of stroke increased. In a multivariate analysis, albuminuria was a predictor of future stroke (30-299 mg/day: HR 1.9 (95% CI 1.03-3.4); 300-999 mg/day: 2.4(1.3-4.6); >1000 mg/day: HR 2.9 (1.6-5.5) independent of Framingham risk score (HR 1.01 (1.0-1.03)), a composite marker of cardiovascular disease risk, or diabetes (HR 1.3 (0.8-2.0)).
Conclusions: Albuminuria is a strong predictor of stroke in patients with CKD. Albuminuria may be a modifiable risk factor with important implications for long-term stroke risk in this population.
- © 2012 by American Heart Association, Inc.