A Transient Improvement in Renal Function Occurs after Ischemic Stroke

Background: Neurohumoral effects have been suggested to affect kidney function. Stroke is a condition where regulation of the renin-angiotensin system and sympathetic nerve activity are altered. Methods: Renal function as estimated by serum creatinine was analyzed over 1 week in 220 patients after acute ischemic stroke. Results: In patients with chronic kidney disease defined as those with serum creatinine >1.2 mg/dL at admission (n = 62), renal function transiently improved, measured by a mean decrease of creatinine of 0.34 mg/dL during the first days after stroke. A significant and transient decrease of creatinine was also observed in patients with diabetes (n = 69) or patients with heart failure (n = 89). In both subgroups creatinine decreased by a mean of 0.49 and 0.24 mg/dL, respectively (p < 0.05 for both). In patients with normal renal function at admission, no change in serum creatinine occurred during the first week after stroke. There was no association between stroke severity and creatinine change. Conclusion: An acute ischemic cerebrovascular event intermittently improves impaired kidney function. The underlying mechanism may involve central regulation of renal function.