Chronic kidney disease in patients with ischemic stroke.

To examine the significance of renal dysfunction in patients who have sustained ischemic stroke, we examined the relationship between the renal function evaluated in terms of estimated glomerular filtration rate (eGFR) and the subtype of brain infarction (BI) in patients with ischemic stroke. A total of 639 patients with BI were enrolled in this study, with 314 subjects without stroke or transient ischemic attack registered as age-matched controls. eGFR was calculated according to the equation 194 × Cr(-1.094) × Age(-0.287) (-0.739 if female), where Cr is serum creatinine concentration, and was classified into four stages: stage I, eGFR ≥ 90 mL/min/1.73 m(2); stage II, eGFR 60 ~ 89 mL/min/1.73 m(2); stage III, eGFR 30 ~ 59 mL/min/1.73 m(2); and stage IV, eGFR <29 mL/min/1.73 m(2). Stage III-IV was significantly more prevalent in the BI group (38%) than in the control group (22%; P < .001). The odds ratio for stage III-IV was significantly higher in the BI group (1.93; 95% confidence interval [CI], 1.35-2.76). Among the BI subgroups, the odds ratios of stage III-IV for the atherothrombotic type (1.81; 95% CI, 1.23-2.68) and the cardiogenic type (2.25; 95% CI, 1.32-3.83) were significantly higher than that of the control group, but that of stage III-IV for lacunar type was not (1.67; 95% CI, 0.98-2.84). Our results indicate that ischemic stroke is frequently associated with renal dysfunction. Chronic kidney disease might be independent risk factor for infarction, especially for cardiogenic and atherosclerotic types.