Background: Higher heart rate (HR) is associated with worse outcomes - in particular death - in long term follow-up of patients with vascular diseases. We investigated the association between HR measured on admission and early in-hospital mortality in acute ischemic stroke patients.
Methods: Over a period of 30 months all patients admitted to our hospital with acute ischemic stroke but without atrial fibrillation were prospectively enrolled. Univariate and multiple logistic regression analyses were conducted to estimate the impact of HR on in-hospital mortality. HR was analyzed as continuous and categorical variable (tertiles).
Results: A total of 1335 patients (median age 73 (IQR 65-81), median National Institutes of Health Stroke Scale score 4 (IQR 2-8), median length of stay 5 days (IQR 4-7), female sex 46%) were studied. In-hospital mortality was 2.6%. When analyzed as categorical variable, HR ≥ 83 bpm was independently associated with in-hospital mortality after adjustment for predictors of poor outcome compared to the reference tertile (HR ≤ 69 bpm) (adjusted odds ratio 4.42, 95% CI 1.36-14.42, p=0.01). When HR was modeled as continuous variable, relative risk for in-hospital death was elevated by 40% for every additional 10-bpm (p=0.003). These results were not changed by including beta-blockers as covariate into the multiple regression model.
Conclusions: HR on admission is independently associated with in-hospital mortality in acute ischemic stroke patients suggesting early negative effects of autonomic imbalance. HR may represent a therapeutic target to improve outcome after ischemic stroke.
Keywords: Heart rate; Mortality; Outcome; Stroke; Sympathetic nervous system.
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