Survival of Stroke Patients According to Hypertension Status in Northern Ethiopia: Seven Years Retrospective Cohort Study

Abstract

Background

Globally, stroke appears as a major cause of preventable deaths and disabilities. In Ethiopia, the intra-hospital mortality of stroke is significant; however, epidemiologic data are scarce whether there is a difference in the overall survival time between hypertensive and non-hypertensive adult stroke patients admitted in specialized hospitals. This study was intended 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 and Findings

A hospital-based retrospective cohort study was conducted among all cohorts of confirmed first-ever stroke patients admitted in Ayder Comprehensive Specialized Hospital, Northern Ethiopia. Kaplan–Meier survival analysis was applied to estimate the survival probability of hypertensive and non-hypertensive first-ever stroke patients. Cox proportional hazards regression model was 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 the Cox proportional hazards regression model assessed by the global test, Schoenfeld residuals. There were 503 (323 were hypertensive, 180 Non-hypertensive) confirmed first, ever adult stroke patients, the overall median age of the patients was 65 years, IQR (53–75) years. Seventy-five (14.9%) of them were dead, with a median survival time of 48 days and 428 (85.1%) 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 intra-hospital patient mortality.

Conclusion

The overall survival time difference between hypertensive and non-hypertensive first-ever adult stroke patients was not statistically significant. Early identification and treatment of stroke complications, co-morbidities along strict follow-up of comatose patients may improve the intra-hospital survival of stroke patients, and we also recommend community-based studies using a large sample size.

Keywords:

• hypertension
• stroke
• cox regression
• predictors of survival
• Ethiopia

Data Sharing Statement

The datasets generated and analyzed during the current study are available from the corresponding author on a reasonable request.

Ethics Approval and Informed Consent

Ethical approval was obtained from Mekelle University, Health Research Ethics Review Committee (ERC 1220/2019). The data collected from the medical records were handled with strong confidentiality, neither the case records nor the data extracted were used for any other purpose and all the collected patient information was stored anonymously. The study was conducted following the Declaration of Helsinki.

Author Contributions

All authors made substantial contributions to conception and design, acquisition of data, or analysis and interpretation of data; took part in drafting the article or revising it critically for important intellectual content; gave final approval of the version to be published; and agree to be accountable for all aspects of the work.

Disclosure

The authors report no conflicts of interest in this work.