Socioeconomic inequities in mortality and functional outcome after stroke in Zanzibar: A prospective cohort study.

OBJECTIVES: To characterise mortality and functional outcome and their relationships with socioeconomic deprivation for women and men in Zanzibar. MATERIALS AND METHODS: Participants in ZanStroke, a prospective observational study of patients admitted to hospital with a diagnosis of acute stroke, were followed up until one year after the stroke. The modified National Institute of Health Stroke Scale was used to assess initial stroke severity, while modified Rankin Scale (mRS) was used to assess disability at 12 months post-stroke. A multidimensional poverty index was created using individual-level data. Kaplan-Meier analysis and Cox regression model were used to examine associations of socioeconomic deprivation and death at 28 days and 12 months after stroke onset, while logistic regression analysis was used to examine associations between deprivation and functional outcome. RESULTS: Overall mortality rate was 38.2% (CI 34.8-41.9) at 28 days, rising to 59.0% (CI 55.2-62.8) at 12 months. When adjusted for other variables, survival was higher among the least deprived (HR 0.60 CI 0.45-0.80), an association that was strongly significant for women (HR 0.46 CI 0.29-0.74). Among 12-month survivors 45.1% (n = 122) had no/low level of disability (mRS 0-2), while 22.9% (n = 62) were unable to walk independently or at all. No difference between socioeconomic deprivation and outcome was seen at one year. CONCLUSION: Case-fatality rates were high, and socioeconomic disparities were evident even during the acute stroke phase. Policies are needed to reduce significant health disparities, adapt evidence-based interventions, and promote equitable access to stroke care and rehabilitation.

Incidence and characteristics of stroke in Zanzibar-a hospital-based prospective study in a low-income island population.

Background: Stroke in adults is a critical clinical condition and a leading cause of death and disability globally. Epidemiological data on stroke in sub-Saharan Africa are limited. This study describes incidence rates, stroke types and antecedent factors among patients hospitalized with stroke in Zanzibar. Methods: This was a prospective, observational study of stroke patients at hospitals in Unguja, Zanzibar. Socioeconomic and demographic data were recorded alongside relevant past medical history, medicine use and risk factors. The modified National Institute of Health Stroke Scale (mNIHSS) was used to assess admission stroke severity and, when possible, stroke was confirmed by neuroimaging. Results: A total of 869 stroke admissions were observed from 1st October 2019 through 30th September 2020. Age-standardized to the World Health Organization global population, the yearly incidence was 286.8 per 100,000 adult population (95%CI: 272.4-301.9). Among these patients, 720 (82.9%) gave consent to participate in the study. Median age of participants was 62 years (53-70), 377 (52.2%) were women, and 463 (64.3%) had a first-ever stroke. Known stroke risk factors included hypertension in 503 (72.3%) patients, of whom 279 (55.5%) reported regularly using antihypertensive medication, of whom 161 (57.7%) had used this medication within the last week before stroke onset. A total of 460 (63.9%) participants had neuroimaging performed; among these there was evidence of intracerebral hemorrhage (ICH) in 140 (30.4%). Median stroke severity score using mNIHSS was 19 (10-27). Conclusion: Zanzibar has high incidence of hospitalization for stroke, indicating a very high population incidence of stroke. The proportion of strokes due to ICH is substantially higher than in high-income countries. Most stroke patients had been in contact with health care providers prior to stroke onset and been diagnosed with hypertension. However, few were using antihypertensive medication at the time of stroke onset.www.ClinicalTrial.gov registration NCT04095806.