Abstract WP227: Risk Factors for Pathophysiologic Subtypes of Ischemic Stroke Among West Africans: Findings From the SIREN Study

Background: The risk factors associated with the occurrence of the distinct pathophysiologic subtypes of ischemic stroke are unknown among indigenous Africans. Objective: To identify and quantify the contributions of risk factors for occurrence of ischemic stroke and its etiologic subtypes among West Africans. Methods: The Stroke Investigative Research and Educational Network (SIREN) is a multicenter, case-control study involving 15 sites in Nigeria and Ghana. Cases included adults aged >18 years with CT/MRI confirmed stroke and ischemic strokes were etiologically subtyped using the TOAST protocol. Controls were age-and-gender matched stroke-free adults recruited from the communities in catchment areas of cases. Comprehensive evaluation for vascular, lifestyle and psychosocial factors was performed using standard instruments. We used conditional logistic regression to estimate odds ratios (OR) with 95% CIs. Results: There were 1,721 ischemic stroke cases with a mean age of 62.19 ± 14.03 vs 60.86 ± 13.71 for controls. Using the TOAST etiologic scheme, 867 (50.3%) were small vessel occlusions, 425(24.7%) were large-artery atherosclerotic, 181(10.5%) were cardio-embolic, 204(11.9%) were undetermined and 44(2.6%) were of other determined etiology. The 7 dominant risk factors for ischemic strokes aOR (95%CI) were hypertension 10.76(7.15-16.20), dyslipidemia 5.30(3.86-7.29), diabetes 3.61(2.72-4.80), psychosocial stress 1.68(1.20-2.35), cardiac disease 1.94 (1.25-3.02), meat consumption 2.02(1.54-2.65), green vegetable consumption 0.44(0.33-0.59). Hypertension, dyslipidemia, diabetes, meat consumption and green vegetable intake were confluent factors shared by small-vessel, large-vessel and cardio-embolic ischemic stroke subtypes. Conclusion: We provide empiric evidence of risk factors to be targeted for stroke prevention. Our findings open a vista into future studies aimed at elucidating the genetic factors linked with pathophysiologic subtypes of stroke among Africans.