Abstract P558: Association Between Stroke Prevalence and Depression, Functional Ability, and Cognitive Function in Six Low and Middle Income Countries: The WHO Study on Global AGEing and Adult Health

Abstract

Background: There are substantial gaps in stroke morbidity in low and middle income countries (LMIC) compared to high income countries (HIC). Stroke incidence and mortality are higher in LMIC compared to HIC. While education has been associated with stroke incidence and common stroke outcomes in HIC, the pattern of this social determinant of health may be reversed in LMIC. We examined the association between stroke prevalence and depression, cognitive function and functional ability utilizing the WHO Study on Global AGEing and Adult Health (SAGE). We also assessed if education modified this association. Methods: We used data from the WHO SAGE, wave 1 (2007-10), which is a nationally representative cohort from six LMIC: China, Ghana, India, Mexico, Russia, and South Africa. Stroke prevalence was classified by self-reported stroke or stroke symptoms. Outcomes included 1) depression [ICD-10 diagnostic criteria]; 2) cognitive function [z-score of performance on executive function, verbal fluency, and memory]; and 3) functional ability [WHO Disability Assessment Schedule]. Generalized linear models were fit for the association between stroke prevalence and outcomes. For our secondary analysis, educational attainment was included as a modifier. All models were adjusted for demographics, socioeconomic status, and health variables. Results: We included 39,896 individuals who had data on their stroke status. Stroke prevalence was 5.1% (n=2,034). Stroke survivors had lower mean cognitive function (-0.1±.8 vs 0.1±0.7, p<0.001), lower functional ability (71.3±21.8 vs 84.6±17.0, p<0.001), and higher percentage of depression (13.0% vs 5.3%, p<0.001) compared to those who did not have a stroke. Prevalence of stroke was associated with significantly higher adjusted odds of depression (Odds Ratio (OR): 1.7; 95% Confidence Interval (CI): 1.3, 2.0), lower cognitive function (Risk Difference (RD): 0.07; 95% CI: -0.1, -0.03), and lower functional ability (RD: -7.4; 95% CI: -8.3, -6.5). Education modified the association of stroke with functional ability but not with depression or cognitive impairment. Stroke survivors with primary or less education had significantly lower physical function than those with tertiary or more (p for interaction=0.04). Conclusion: Stroke was associated with a higher odds of depression and higher risk of reduced cognitive function and functional ability. Unlike in HIC, these six LMIC did not display a significant inverse association between education and depression and cognitive function. Future studies should assess predictors of poorer post-stroke outcomes and if other socioeconomic measures modify consequences of stroke in LMIC.