Reduced kidney function and outcome in acute ischaemic stroke: relationship to arterial hypertension and diabetes

BACKGROUND: Stroke is a dangerous long-term complication of kidney failure, yet its occurrence early in disease is poorly characterized. Our aim was to investigate the association of reduced kidney function, hypertension and diabetes with acute ischaemic stroke and the outcome thereof. METHODS: In this prospective cohort study, the association of reduced kidney function, hypertension and diabetes with stroke and 2-year all-cause mortality was investigated. Glomerular filtration rate (eGFR) was estimated by the simplified Modification of Diet in Renal Disease formula in 13 365 consecutive patients (671 with acute ischaemic stroke) admitted to our clinical facility over a 12-month period. RESULTS: Ischaemic stroke, after adjustment for age and gender, was significantly associated with eGFR <60 mL/min/1.73m(2) [odds ratio (OR) 1.53, 95% confidence interval (CI) 1.30-1.81], hypertension (2.77, 95% CI 2.33-3.28) and diabetes (1.30, 95% CI 1.04-1.63). Multivariate analysis of interaction indicated the absence of an additive effect between eGFR, hypertension and diabetes, on the risk of stroke. Age and gender-adjusted survival analysis by Cox regression showed an association of mortality with reduced eGFR alone (HR = 4.29, 95% CI 1.02-19.60). CONCLUSIONS: In patients acutely admitted to hospital, reduced kidney function, hypertension and diabetes are independently associated with ischaemic stroke, but do not exert a synergic effect. After hospital discharge, mortality is strongly associated with reduced eGFR but with neither hypertension nor diabetes.