Abstract TP285: Serum Potassium Levels Influence Ischemic Stroke Outcome

Abstract

Introduction: In cardiac literature hypokalemia has been shown to be assoicated with poor outcomes. It remains unclear whether specific electrolytes, namely potassium, influence stroke outcomes. Our goal in this retrospective study was to test whether the serum electrolyte level at admission and discharge is related to NIHSS and discharge mRS. Methods: We conducted a retrospective analysis of ischemic patients admitted to Neuro-ICU between December 2004 and December 2009 at a community teaching hospital. Patient electrolyte levels were documented at admission and discharge as well as discharge mRS. Patients were then divided into groups based on their admission potassium levels as follows: hypokalemic patients (K+ less than 3.5), normokalemic patients (K+ 3.5-5.0), and hyperkalemic patients (K+ greater than 5) and their means were compared in respect to discharge mRS using SPSS software version 20. Results: Of 1350 patients, 543 (mean age = 72.5 +/- 14.2, 56% female) were included. Mean potassium level at admission and discharge were 4.31+/- 0.77 mEq/L and 4.12 +/- 0.50 mEq/L, respectively. There was a significant difference between admission and discharge potassium levels, p <0.001. Hypokalemic patients had a significantly higher mRS score than normokalemic patients, p < .05 at admission (p < 0.05) and at discharge (p < 0.05). Hypokalemic patients had a significantly higher NIHSS than normokalemic patients, p < .05. Hypokalemic patients of age ≥ 65 at admission (p <0.05) and at discharge (p < 0.05) had a significantly higher mRS than normokalemic patients. This effect was not seen in patients < 65 years of age. Conclusion: Our study suggests that patients with serum potassium levels below normal levels initially and at discharge have worse outcomes , especially in elderly patients. A larger prospective study is warranted to study the effect of endogenous potassium in long term outcomes of patients with ischemic stroke.