Survival of stroke patients according to hypertension status in Northern Ethiopia

Abstract

Background: Globally, stroke appears as a major cause of preventable death and disability. In Ethiopia, the intra-hospital mortality of stroke is significant and there is scarcity of epidemiologic data whether there is a difference in the overall survival time between hypertensive and non-hypertensive adult stroke patients admitted in specialized hospitals. Objectives: To determine the survival of stroke patients according to their hypertension status admitted in Ayder Comprehensive Specialized Hospital, Northern Ethiopia from March 1, 2012 to February 28, 2019. Methods: A facility-based retrospective cohort study conducted among all cohorts of confirmed first-ever stroke patients admitted in Ayder Comprehensive Specialized Hospital, Northern Ethiopia. Kaplan-Meier survival analysis applied to estimate the survival probability of hypertensive and non-hypertensive first ever stroke patients. Cox proportional hazards regression model used to determine the adjusted hazard ratio of death for each main baseline predictor variable, with 95% CI and P-value <0.05 was used to declare statistical significance. The assumptions of Cox proportional hazards regression model assessed by the global test, Schoenfeld residuals. Results: There were 503 (323 were hypertensive, 180 Non-hypertensive) confirmed first, ever stroke patients, the overall median age of the patients was 65 years, IQR (53-75) years. Seventy-five (14.91%) of them were dead, with median survival time of 48 days and 428 (85.09%) of them were censored. At any particular point in time the hazard of death among hypertensive patients was two times higher than non-hypertensive patients but this was not found to be a statistically significant (adjusted HR=2.13: 95% CI 0.66-6.81). Glasgow coma scale 3-8 at admission (adjusted HR=10.12; 95% CI 2.58-40.68), presence of stroke complications (adjusted HR=7.23; 95% CI 1.86-28.26) and borderline high total cholesterol level (adjusted HR=3.57; 95% CI 1.15-11.1), were the only independent predictors of intrahospital patient mortality. Conclusion and recommendations: There was a non-significant difference in the overall survival time between hypertensive and non-hypertensive first-ever stroke patients. Early identification and treatment of stroke complications, co-morbidities along with strict follow up of comatose patients may improve intra-hospital survival of stroke patients and we recommend community based studies using large sample size.