Background: Reduced glomerular filtration rate and albuminuria are associated with an increased risk for stroke. Their association with stroke symptoms is not known.
Methods: The incidence of stroke symptoms was determined in 20 386 participants ≥45 years of age in the REasons for Geographic and Racial Differences in Stroke (REGARDS) study who were free of a history of stroke, transient ischemic attack and stroke symptoms at baseline. Six stroke symptoms were assessed via telephone interviews at baseline and every 6 months. Participants were followed over a median of 2.1 years (maximum follow-up of 6 years). Estimated glomerular filtration rate (eGFR) was calculated using the CKD-EPI equation and the albumin-to-creatinine ratio from spot urine samples.
Results: The incidence of any stroke symptom (n = 2548 cases) was 10.8, 12.9, 18.2 and 20.7% among participants with an eGFR ≥90, 60-89, 45-59 and <45 mL/min/1.73m(2), respectively, and 10.8, 14.4, 17.0 and 18.8 for participants with albumin-to-creatinine ratios <10, 10-29, 30-299 and ≥300 mg/g, respectively (each P-trend < 0.001). The multivariable-adjusted hazard ratio (95% confidence interval) for any stroke symptom was 1.02 (0.91-1.14), 1.22 (1.01-1.48) and 1.26 (0.98-1.62) for those with an eGFR of 60-89, 45-59 and <45 mL/min/1.73m(2), respectively, versus ≥90 mL/min/1.73m(2) (P-trend = 0.022) and 1.16 (1.03-1.31), 1.29 (1.12-1.50) and 1.11 (0.82-1.49) for those with albumin-to-creatinine ratios of 10-29, 30-299 and ≥300 versus <10 mg/g, respectively (P-trend = 0.005).
Conclusions: Reduced eGFR and higher albuminuria levels are associated with an increased risk for incident stroke symptoms.