Increased Risk of Ischemic Stroke in Patients with Chronic Kidney Disease after Recurrent Dysnatremias: A Nationwide Population-Based Cohort Study

Abstract

Dysnatremias are the common problems in chronic kidney disease (CKD) patients and associated with neurologic symptoms. Thus, the purpose of this study was to determine the association between dysnatremias (either hypernatremia or hyponatremia) and risk of stroke in CKD population. A retrospective cohort study was constructed using the claims data of the entire insured residents covered by Taiwan's universal health insurance from 2000 to 2011. Severe hyponatremia and hypernatremia are defined as the need of 3% sodium chloride treatment and the need of admission respectively. A total of 365 hyponatremia and 137 hypernatremia patients and 1983 matched comparisons were recruited. The incidence of stroke was defined using the International Classification of Diseases, 9th Revision, Clinical Modification. Cox proportional hazard regression and Kaplan-Meier curves were used for the analyses. In the analysis, CKD with dysnatremias were with more diabetes, heart failure, mental illness, liver cirrhosis, cancer history and diuretics treatment. Compared with comparisons, patients with dysnatremias, hyponatremia or hypernatremia patients had a 2.57 (95% CI: 1.91-3.46), 2.35 (95% CI: 1.67-3.29) and 3.35 (95% CI: 2.04-5.50) fold risks of stroke after adjusting for potential factors. There was similarly increased risk for ischemic stroke, but not for hemorrhagic stroke. In addition, patients with recurrent dysnatremias, the risk of stroke much increased ) for hyponatremia and 11.4 (95% CI: 5.66-23.1) for hypernatremia]. In conclusion, we suggest more intensive surveillance to prevent recurrent dysnatremias and ischemic stroke should be emphasized.