Significance of Hypokalemia in Functional Outcomes of Patients with Subacute Stroke

Abstract

This retrospective case-control study aimed to the effect of hypokalemia on the functional outcomes of patients with subacute stroke. A total of 96 post-stroke hemiplegic patients admitted to an inpatient clinic of the department of rehabilitation medicine between March 2014 and February 2018 were recruited. Serum potassium level was assessed at the time of admission, and the patients with hypokalemia on admission or within 7 days after onset were classified into the hypokalemic group. Functional assessments using the Hemispheric Stroke Scale (HSS), Functional Ambulation Category (FAC), Functional Independence Measure for locomotion, and Mini Mental Status Examination were performed. The primary outcome was the change in functional score during rehabilitation. No significant intergroup differences in baseline characteristics were found except hospital stay duration and use of diuretics. FAC recovery (0.91 vs. 1.66, p = 0.001), HSS lower extremity and total motor scores (0.37 vs. 1.10, p = 0.01; 0.83 vs. 2.18, p = 0.02, respectively) were significantly lower in the hypokalemic group. Pearson correlation analysis of the initial serum potassium level and functional recovery revealed significant correlations with the FAC or HSS lower extremity and total motor scores (p = 0.001, p = 0.01, and p = 0.04, respectively).