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Background and Purpose: To identify the qualitative and quantitative contributions of conventional risk factors for occurrence of ischemic stroke and its key pathophysiologic subtypes among West Africans., Methods: The SIREN (Stroke Investigative Research and Educational Network) is a multicenter, case-control study involving 15 sites in Ghana and Nigeria. Cases include adults aged ≥18 years with ischemic stroke who were etiologically subtyped using the A-S-C-O-D classification into atherosclerosis, small-vessel occlusion, cardiac pathology, other causes, and dissection. Controls were age- and gender-matched stroke-free adults. Detailed evaluations for vascular, lifestyle, and psychosocial factors were performed. We used conditional logistic regression to estimate adjusted odds ratios with 95% CI., Results: There were 2431 ischemic stroke case and stroke-free control pairs with respective mean ages of 62.2±14.0 versus 60.9±13.7 years. There were 1024 (42.1%) small vessel occlusions, 427 (17.6%) large-artery atherosclerosis, 258 (10.6%) cardio-embolic, 3 (0.1%) carotid dissections, and 719 (29.6%) undetermined/other causes. The adjusted odds ratio (95% CI) for the 8 dominant risk factors for ischemic stroke were hypertension, 10.34 (6.91-15.45); dyslipidemia, 5.16 (3.78-7.03); diabetes, 3.44 (2.60-4.56); low green vegetable consumption, 1.89 (1.45-2.46); red meat consumption, 1.89 (1.45-2.46); cardiac disease, 1.88 (1.22-2.90); monthly income $100 or more, 1.72 (1.24-2.39); and psychosocial stress, 1.62 (1.18-2.21). Hypertension, dyslipidemia, diabetes were confluent factors shared by small-vessel, large-vessel and cardio-embolic subtypes. Stroke cases and stroke-free controls had a mean of 5.3±1.5 versus 3.2±1.0 adverse cardio-metabolic risk factors respectively ( P <0.0001)., Conclusions: Traditional vascular risk factors demonstrate important differential effect sizes with pathophysiologic, clinical and preventative implications on the occurrence of ischemic stroke among indigenous West Africans.

Objective: To characterize risk factors for spontaneous intracerebral hemorrhage (sICH) occurrence and severity among West Africans., Methods: The Stroke Investigative Research and Educational Network (SIREN) study is a multicenter case-control study involving 15 sites in Ghana and Nigeria. Patients were adults ≥18 years old with CT-confirmed sICH with age-, sex-, and ethnicity-matched stroke-free community controls. Standard instruments were used to assess vascular, lifestyle, and psychosocial factors. Factors associated with sICH and its severity were assessed using conditional logistic regression to estimate odds ratios (ORs) and population-attributable risks (PARs) with 95% confidence intervals (CIs) for factors., Results: Of 2,944 adjudicated stroke cases, 854 were intracerebral hemorrhage (ICH). Mean age of patients with ICH was 54.7 ± 13.9 years, with a male preponderance (63.1%), and 77.3% were nonlobar. Etiologic subtypes of sICH included hypertension (80.9%), structural vascular anomalies (4.0%), cerebral amyloid angiopathy (0.7%), systemic illnesses (0.5%), medication-related (0.4%), and undetermined (13.7%). Eight factors independently associated with sICH occurrence by decreasing order of PAR with their adjusted OR (95% CI) were hypertension, 66.63 (20.78-213.72); dyslipidemia, 2.95 (1.84-4.74); meat consumption, 1.55 (1.01-2.38); family history of CVD, 2.22 (1.41-3.50); nonconsumption of green vegetables, 3.61 (2.07-6.31); diabetes mellitus, 2.11 (1.29-3.46); stress, 1.68 (1.03-2.77); and current tobacco use, 14.27 (2.09-97.47). Factors associated with severe sICH using an NIH Stroke Scale score >15 with adjusted OR (95% CI) were nonconsumption of leafy green vegetables, 2.03 (1.43-2.88); systolic blood pressure for each mm Hg rise, 1.01 (1.00-1.01); presence of midline shift, 1.54 (1.11-2.13); lobar ICH, 1.72 (1.16-2.55); and supratentorial bleeds, 2.17 (1.06-4.46)., Conclusions: Population-level control of the dominant factors will substantially mitigate the burden of sICH in West Africa., (© 2020 American Academy of Neurology.)

Background and Purpose- The interplay between sex and the dominant risk factors for stroke occurrence in sub-Saharan Africa has not been clearly delineated. We compared the effect sizes of risk factors of stroke by sex among West Africans. Methods- SIREN study (Stroke Investigative Research and Educational Networks) is a case-control study conducted at 15 sites in Ghana and Nigeria. Cases were adults aged >18 years with computerized tomography/magnetic resonance imaging confirmed stroke, and controls were age- and sex-matched stroke-free adults. Comprehensive evaluation for vascular, lifestyle, and psychosocial factors was performed using validated tools. We used conditional logistic regression to estimate odds ratios and reported risk factor specific and composite population attributable risks with 95% CIs. Results- Of the 2118 stroke cases, 1193 (56.3%) were males. The mean±SD age of males was 58.1±13.2 versus 60.15±14.53 years among females. Shared modifiable risk factors for stroke with adjusted odds ratios (95% CI) among females versus males, respectively, were hypertension [29.95 (12.49-71.77) versus 16.1 0(9.19-28.19)], dyslipidemia [2.08 (1.42-3.06) versus 1.83 (1.29-2.59)], diabetes mellitus [3.18 (2.11-4.78) versus 2.19 (1.53-3.15)], stress [2.34 (1.48-3.67) versus 1.61 (1.07-2.43)], and low consumption of green leafy vegetables [2.92 (1.89-4.50) versus 2.00 (1.33-3.00)]. However, salt intake and income were significantly different between males and females. Six modifiable factors had a combined population attributable risk of 99.1% (98.3%-99.6%) among females with 9 factors accounting for 97.2% (94.9%-98.7%) among males. Hemorrhagic stroke was more common among males (36.0%) than among females (27.6%), but stroke was less severe among males than females. Conclusions- Overall, risk factors for stroke occurrence are commonly shared by both sexes in West Africa favoring concerted interventions for stroke prevention in the region.