Background: As the second leading cause of death and the leading cause of adult-onset disability, stroke is a major public health concern particularly pertinent in Sub-Saharan Africa (SSA), where nearly 80% of all global stroke mortalities occur, and stroke burden is projected to increase in the coming decades. However, traditional and emerging risk factors for stroke in SSA have not been well characterized, thus limiting efforts at curbing its devastating toll. The Stroke Investigative Research and Education Network (SIREN) project is aimed at comprehensively evaluating the key environmental and genomic risk factors for stroke (and its subtypes) in SSA while simultaneously building capacities in phenomics, biobanking, genomics, biostatistics, and bioinformatics for brain research. Methods: SIREN is a transnational, multicentre, hospital and community-based study involving 3,000 cases and 3,000 controls recruited from 8 sites in Ghana and Nigeria. Cases will be hospital-based patients with first stroke within 10 days of onset in whom neurovascular imaging will be performed. Etiological and topographical stroke subtypes will be documented for all cases. Controls will be hospital- and community-based participants, matched to cases on the basis of gender, ethnicity, and age (±5 years). Information will be collected on known and proposed emerging risk factors for stroke. Study Significance: SIREN is the largest study of stroke in Africa to date. It is anticipated that it will shed light on the phenotypic characteristics and risk factors of stroke and ultimately provide evidence base for strategic interventions to curtail the burgeoning burden of stroke on the sub-continent.

Background and Purpose The Questionnaire for Verifying Stroke-free Status (QVSFS), a method for verifying stroke-free status in participants of clinical, epidemiological and genetic studies, has not been validated in low-income settings where populations have limited knowledge of stroke symptoms. We aimed to validate QVSFS in 3 languages-Yoruba, Hausa and Akan- for ascertainment of stroke-free status of control subjects enrolled in an ongoing stroke epidemiological study in West Africa. Methods Data were collected using a cross-sectional study design where 384 participants were consecutively recruited from neurology and general medicine clinics of 5 tertiary referral hospitals in Nigeria and Ghana. Ascertainment of stroke status was by neurologists using structured neurological examination, review of case records and neuro-imaging (Gold standard). Relative performance of QVSFS without and with pictures of stroke symptoms (pictograms) was assessed using sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Results The overall median age of the study participants was 54 years and 48.4% were males. Of 165 stroke cases identified by Gold standard, 98% were determined to have had stroke while of 219 without stroke 87% were determined to be stroke-free by QVSFS. NPV of the QVSFS across the 3 languages was 0.97 (range, 0.93 – 1.00), sensitivity, specificity and PPV were 0.98, 0.82 and 0.80 respectively. Agreement between the questionnaire with and without the pictogram was excellent/strong with Cohen’s k=0.92. Conclusions QVSFS is a valid tool for verifying stroke-free status across culturally diverse populations in West Africa.

Background Africa has a growing burden of stroke with associated high morbidity and a 3-year fatality rate of 84%. Cardiac disease contributes to stroke occurrence and outcomes, but the precise relationship of abnormalities as noted on a cheap and widely available test, the electrocardiogram (ECG), and acute stroke outcomes has not been previously characterized in Africans. We assessed the prevalence and prognoses of various ECG abnormalities among African acute stroke patients encountered in a multisite, cross-national epidemiologic study. Methods We included 890 patients from Nigeria and Ghana with acute stroke who had 12-lead ECG recording within first 24 hours of admission and stroke classified based on brain CT scan or MRI. Stroke severity at baseline was assessed using the Stroke levity scale (SLS), while one-month outcome was assessed using the modified Rankin scale (mRS). Results Patients mean age was 58.4 (±13.4) years, 490 were male (55%) and 400(45%) females, 65.5% had ischemic stroke, and 85.4% had at least one ECG abnormality. Women were significantly more likely to have atrial fibrillation, or left ventricular hypertrophy (LVH) with or without strain pattern. Compared to ischemic stroke patients, hemorrhagic stroke patients were less likely to have atrial fibrillation (1.0% vs. 6.7%, p=0.002), but more likely to have LVH (64.4% vs. 51.4%, p=0.004). Odds of severe disability or death at one month was higher with severe stroke (AOR: 2.25; 95% CI :1.44–3.50), or atrial enlargement (AOR: 1.45; CI:1.04–2.02). Conclusions About four in five acute stroke patients in this African cohort had evidence of a baseline ECG abnormality, but presence of any atrial enlargement was the only independent ECG predictor of death or disability.

Background: The relationship of diet with stroke risk among Africans is not well understood. Aim: To investigate the association between dietary patterns and stroke risk among West Africans. Methods: In this multi-centre case-control study, 3684 stroke patients matched (for age and sex) with 3684 healthy controls were recruited from Nigeria and Ghana. Food consumption was assessed using a food frequency questionnaire, and dietary patterns were summarized using principal component analysis. Stroke was defined using predefined criteria primarily on clinical evaluation following standard guidelines. Conditional logistic regression was applied to compute odds ratio (OR) and 95% confidence interval (CI) for stroke risk by tertiles of dietary patterns. Results: Overall, mean age was 59.0±13.9 years, and 3992(54.2%) were males. Seven dietary patterns were identified. Multivariable-adjusted OR (95%CI) for risk of stroke by second and third tertiles (using the lowest (first) tertile as reference) of dietary patterns were; 1.65 (1.43, 1.90) and 1.74 (1.51, 2.02) respectively for ‘poultry product and organ meat’; 1.69 (1.47, 1.96 and, 1.51 (1.31, 1.75) for ‘red meat’; 1.07 (0.92, 1.23) and 1.21 (1.04, 1.40) for ‘fried foods and sweetened drinks’; 0.69 (0.60, 0.80) and 0.45 (0.39, 0.53) for ‘vegetables’; 0.84 (0.72, 0.97) and 0.81 (0.70, 0.93) for ‘whole-grain and fruit drinks’; and 0.97 (0.84, 1.12) and 0.85 (0.73, 0.98) for ‘fruits’ (P<0.05). Conclusions: These data suggest that plant-based diets are associated with a lower risk of stroke and might be a beneficial dietary recommendation for the primary prevention of stroke among Africans.

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Introduction Genomic research and neurobiobanking are expanding globally. Empirical evidence on the level of awareness and willingness to donate/share biological samples towards the expansion of neurobiobanking in sub-Saharan Africa is lacking. Aims To ascertain the awareness, perspectives and predictors regarding biological sample donation, sharing and informed consent preferences among community members in Ghana and Nigeria. Methods A questionnaire cross-sectional survey was conducted among randomly selected community members from seven communities in Ghana and Nigeria. Results Of the 1015 respondents with mean age 39.3 years (SD 19.5), about a third had heard of blood donation (37.2%, M: 42.4%, F: 32.0%, p = 0.001) and a quarter were aware of blood sample storage for research (24.5%; M: 29.7%, F: 19.4%, p = 0.151). Two out of ten were willing to donate brain after death (18.8%, M: 22.6%, F: 15.0%, p<0.001). Main reasons for unwillingness to donate brain were; to go back to God complete (46.6%) and lack of knowledge related to brain donation (32.7%). Only a third of the participants were aware of informed consent (31.7%; M: 35.9%, F: 27.5%, p<0.001). Predictors of positive attitude towards biobanking and informed consent were being married, tertiary level education, student status, and belonging to select ethnic groups. Conclusion There is a greater need for research attention in the area of brain banking and informed consent. Improved context-sensitive public education on neurobiobanking and informed consent, in line with the sociocultural diversities, is recommended within the African sub region.

The study evaluates the potential immunocytotoxic effect of aqueous leaf extract of Cassia occidentalis on human peripheral blood mononuclear cells (PBMCs) and Neutrophils. Different concentrations (25 µg/ml, 50 µg/ml, 100 µg/ml) of the extract were prepared. Six millilitres (6ml) of peripheral blood from consented healthy volunteers was collected and PBMCs and neutrophils were isolated on Histopaque media. The viability of PBMCs and neutrophils was determined using trypan blue dye exclusion methods. One-way analysis of variance was used in analysing the results. Total viable cell count (TVCC) for PBMCs and neutrophils yielded 298.9 x 104 cells/ml and 327.9 x 104 cells/ml respectively. The TVCC of the highest concentration (100 µg/ml) of the extract used for the treatment of PBMCs was 192.7 x104 cells/ml and that of neutrophil was 50.47 x104 cells/ml equivalent to 82.51% and 61.71% mean viability percentages respectively. The PBMCs and neutrophils treated with 25 µg /ml of the extract have the highest mean percentage viability scores of 94.88% and 74.61% respectively. There was a significant difference in the mean percentage viability when control PBMCs was compared with those treated with 100 µg/ml (p<0.0001) and also when control neutrophils was compared with those treated with 25 µg /ml (p=0 .02), 50 µg /ml and 100 µg /ml (p<0.0001) respectively. The cell viability tends to decrease in a dose-dependent manner. The aqueous leaf extract of C. occidentalis has a potent cytotoxic effect on both cells, especially at a higher dose. The study recommends an in-depth study to improve the credence of the present study findings. Keywords: Cassia occidentalis extract, Cytotoxic activity, Human Neutrophils and PBMCs

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.