Search

Aims The relationship between vegetable consumption and hypertension occurrence remains poorly characterized in sub-Saharan Africa. This study assessed the association of vegetable consumption with odds of hypertension among indigenous Africans. Methods and results We harmonized data on prior vegetable consumption and hypertension occurrence (defined as one of the following conditions; systolic blood pressure ≥140 or diastolic blood pressure ≥90 mmHg or previous diagnosis or use of antihypertensive medications) from 16 445 participants across five African countries (Nigeria, South Africa, Kenya, Ghana and Burkina Faso) in the Stroke Investigative Research and Educational Network and Africa Wits-INDEPTH partnership for Genomic studies. Vegetable consumption (in servings/week) was classified as ‘low’ ( Conclusion Indigenous Africans who consumed at least 12 servings of vegetables per week were less likely to be found hypertensive, particularly among males and young adults.

Background: The relationship of diet with stroke risk among Africans is not well understood. Aim: The aim of this study was to investigate the association between dietary patterns and stroke risk among West Africans. Methods: In this multi-center 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 adjusting for relevant confounders. 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 and first tertile as reference) of dietary patterns was 1.65 (1.43, 1.90) and 1.74 (1.51, 2.02), 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” respectively ( p Conclusion: 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.

Background: The association of vegetable consumption with hypertension remains poorly described in sub-Saharan Africa. This study assessed the relationship between vegetable consumption and hypertension among indigenous Africans. Methods: We harmonized data on the frequency of vegetable consumption (servings/week) and hypertension (defined as systolic blood pressure ≥ 140mmHg or diastolic blood pressure ≥ 90mmHg or previous diagnosis or use of antihypertensive medications) from 16,445 participants across five African countries (Ghana, Burkina Faso, Kenya, Nigeria and South Africa) from the SIREN and AWI-Gen studies. Using the recommendation of at least five servings/day (35 servings/week) adapted from the World Health Organization recommendations, and vegetable consumption was classified as 'inadequate' (P Results: The mean age of participants was 53.0±10.7years, 45.9% (7,552 of 16,445) were males, and 42.9% (7,070 of 16,445) were hypertensives. Adequate vegetable consumption was associated with lower odds of hypertension; OR: 0.86 (95%CI: 0.76, 0.97). The sex-stratified odds was; OR: 0.87 (95%CI: 0.73, 1.02) for females and 0.84 (95%CI: 0.71, 1.00) for males. Conclusion: These findings provide new evidence for promoting regular vegetable consumption in the guidelines for the primary prevention of hypertension among Africans.

Low-field (, Accepted in Medical Image Analysis

Hypertension is one of the most important risk factors for stroke and cardiovascular diseases (CVD) globally. Understanding risk factors for hypertension among individuals with matching characteristics with stroke patients may inform primordial/primary prevention of hypertension and stroke among them. This study identified the risk factors for hypertension among community‐dwelling stroke‐free population in Ghana and Nigeria. Data for 4267 community‐dwelling stroke‐free controls subjects in the Stroke Investigative Research and Education Network (SIREN) study in Nigeria and Ghana were used. Participants were comprehensively assessed for sociodemographic, lifestyle and metabolic factors using standard methods. Hypertension was defined as a previous diagnosis by a health professional or use of an anti‐hypertensive drug or mean systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg. Logistic regression analysis was used to estimate adjusted odds ratios (aOR) of hypertension and their 95% confidence intervals (CI) at p

SummaryMRI technology has profoundly transformed current healthcare and research systems globally. The rapidly growing burden of non-communicable diseases in Africa has underscored the importance of improving access to MRI equipment as well as training and research opportunities on the continent. The Consortium for Advancement of MRI Education & Research in Africa (CAMERA) is a network of African experts, global partners, and ISMRM/ESMRMB members implementing novel strategies to advance MRI access and research in Africa. To identify challenges to MRI usage and provide a framework for addressing MRI needs in the region, CAMERA conducted a Needs Assessment Survey (NAS) and a series of symposia at international MRI society meetings over a 2-year period. The 68-question NAS was distributed to MRI users in Africa and completed by 157 clinicians and scientists from across Sub-Saharan Africa (SSA). On average, the number of MRI scanners per million people remained at Graphical AbstractAfrica has a massive population with few infrastructural resources and an untapped potential to effect transformative change in healthcare. To advance MRI access across all African countries and meet the sustainable development goals of improving health and wellbeing in low-resource settings over the next decade, the MRI community is called to partner with CAMERA to create enabling clinical and research MRI environments that will utilize the rich intellectual resources in Africa to realize lasting and equitable MRI for all Africans and the world at large.

Background: Seizure is the most common neurological disorder in children and an important cause of paediatric hospital admission with the highest prevalence in the under-five age group. Magnetic Resonance Imaging (MRI) is the neuro-imaging technique of choice in the initial evaluation of children with epilepsy. High-field MRI is the ideal imaging modality for evaluating seizures but this is not readily available in developing countries. Objective: To analyse the spectrum of MRI findings in children presenting with seizures using a low-field (0.36T) MRI. Methods: Children aged ≤18years with seizures, with cranial MRI at the University College Hospital (UCH), Nigeria between January 2013 and June 2015 were retrospectively reviewed. Results: There were a total of 134 patients with 53% as adolescents and most of them (85; 63.4%) had abnormal cranial MRI findings. More male children had abnormal findings (52; 61.2%) and most abnormal findings (42; 49.4%) were reported among adolescents. The most frequent abnormality was hydrocephalus (23.5%) from various causes followed by cerebral tumours (14.1%) and ischaemic cerebral infarcts (11.8%). In the adolescents, intracranial tumours (21.4%) were the most frequent abnormal findings, while hydrocephalus was commoner in children aged less than 10 years, accounting for 33.3% and 36.0% among the 1-5 years and 6-11 years age groups respectively. Conclusion: Low-field MRI, which is more readily available, can provide substantial preliminary findings to aid the management of children with epilepsies. Improved access to high-field MRI through cost reduction and early MR imaging evaluation in the course of illness are desirable.

Objectives: Depression is a risk factor for stroke. There is a knowledge gap on the predictors of prestroke depression in stroke survivors living in low- and middle-income countries (LMICs). We estimated prevalence and predictors of prestroke depression, as well as its association with poststroke depression (PSD) in the largest study of stroke in Africa. Methods: We evaluated information collected as part of the Stroke Investigative Research and Education Network (SIREN) study, a multicentre, case-control study conducted at 15 sites in Ghana and Nigeria. Prestroke depression status was ascertained in stroke survivors using a validated self-report tool, while PSD was assessed using a stroke specific screening tool for depression (“HRQOLISP-E”). Independent associations were investigated using complementary log-log regression and binary logit models. Results: Among 1,977 participants, prestroke depression was found in 141 (7.1%). In multivariate analyses, prestroke depression was significantly associated with tachycardia (OR = 2.22, 95% CI = 1.37-3.56) and low consumption of green leafy vegetables (OR = 1.91, 95% CI = 1.12-3.24). Forty-one (29.1%) of the prestroke depression sub-sample developed PSD. However, prestroke depression was not significantly associated with PSD. Conclusion: The findings should energize before-the-stroke identification and prioritization of limited treatment resources in LMICs to persons with depression who have multiple, additional, risks of stroke.

Africa is the world’s most genetically diverse, second largest, and second most populous continent, with over one billion people distributed across 54 countries. With a 23% lifetime risk of stroke, Africa has some of the highest rates of stroke worldwide and many occur in the prime of life with huge economic losses and grave implications for the individual, family, and the society in terms of mental capital, productivity, and socioeconomic progress. Tackling the escalating burden of stroke in Africa requires prioritized, multipronged, and inter-sectoral strategies tailored to the unique African epidemiological, cultural, socioeconomic, and lifestyle landscape. The African Stroke Organization (ASO) is a new pan-African coalition that brings together stroke researchers, clinicians, and other health-care professionals with participation of national and regional stroke societies and stroke support organizations. With a vision to reduce the rapidly increasing burden of stroke in Africa, the ASO has a four-pronged focus on (1) research, (2) capacity building, (3) development of stroke services, and (4) collaboration with all stakeholders. This will be delivered through advocacy, awareness, and empowerment initiatives to bring about people-focused changes in policy, clinical practice, and public education. In the spirit of the African philosophy of Ubuntu “I am because we are,” the ASO will harness the power of diversity, inclusiveness, togetherness, and team work to build a strong, enduring, and impactful platform for tackling stroke in Africa.

The objective of this study was to evaluate the thyroid glands' radiation dose and the risk of thyroid cancer induction from head or neck computed tomography (CT) examinations.In a prospective study, we evaluated all participants of all ages and sex referred for Head or Neck CT Scan at the University College Hospital, Ibadan and Me Cure Healthcare Limited, Ibadan, Oyo State, Nigeria. Thyroid radiation dose was estimated with impact scan calculator, and real-time dose measurement with thermoluminescent badge dosimeters (TLDs). Data were analysed and P0.05 was considered statistically significant.One hundred and sixty-three participants (128 adults and 35 children) participated in the study. In most participants (74%), the tube voltage was 120 kVp. The estimated median thyroid gland dose by the imPACT scan calculator was 4.95 mGy (range = 1.20-30.0 mGy) and 4.40 mGy (range = 3.0-5.10 mGy), while the real-time dose measured by the TLD was 4.79 mGy (range = 1.73-96.7 mGy) and 2.33 mGy (range = 1.20-3.73 mGy) at Centre A and B, respectively. The estimated median thyroid cancer risk was 2.88 × 10Scanner specifications and technique may significantly contribute to variations seen in thyroid radiation doses. There may be a need to optimise centre protocols and apply dose reference levels for head and neck CT examinations to reduce thyroid cancer risk in Nigeria.

Objectives To explore the prevalence and risk factors of obesity among older adults from low- and middle-income countries (LMICs). Methods This is a secondary analysis of data obtained from the SIREN study through in-person interviews and measurements from healthy stroke-free older adults (≥60 years). Overweight/obesity was defined as body mass index ≥25 kg/m2. Abdominal obesity was defined as waist-to-hip ratio (WHR) of >0.90 for males and >0.85/females or waist circumference (WC) of >102 cm for males/>88 cm for females. Adjusted odds ratio (aORs) with 95% confidence interval (CIs) of the relationship between obesity and sociodemographic factors were assessed at P Results Overall, 47.5% of participants were overweight/obese, 76.6% had a larger than recommended WHR, and 54.4% had a larger than recommended WC. Abdominal obesity (WC; aOR: 9.43, CI: 6.99–12.50), being a Nigerian (aOR: 0.55; CI: 0.42–0.72), living in an urban setting (aOR: 1.92; CI: 1.49–2.46 ), earning >$100/month (aOR: 1.53; CI: 1.19–1.96), and having formal education (aOR: 1.42; CI: 1.08–1.87) were associated with overweight/obesity. Conclusion Living in urban settings, earning a higher income, and having a formal education were associated with a higher odds of obesity among older adults from LMICs.

Low-field MR scanners are more accessible in resource-constrained settings where skilled personnel are scarce. Images acquired in such scenarios are prone to artifacts such as wrap-around and Gibbs ringing. Such artifacts negatively affect the diagnostic quality and may be confused with pathology or reduce the region of interest visibility. As a first step solution, ArtifactID identifies wrap-around and Gibbs ringing in low-field brain MRI. We utilized two datasets: 179 T

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 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.

International audience; In tandem with the ever-increasing aging population in low and middle-income countries, the burden of dementia is rising on the African continent. Dementia prevalence varies from 2.3% to 20.0% and incidence rates are 13.3 per 1000 person-years with increasing mortality in parts of rapidly transforming Africa. Differences in nutrition, cardiovascular factors, comorbidities, infections, mortality, and detection likely contribute to lower incidence. Alzheimer's disease, vascular dementia, and human immunodeficiency virus/acquired immunodeficiency syndrome-associated neurocognitive disorders are the most common dementia subtypes. Comprehensive longitudinal studies with robust methodology and regional coverage would provide more reliable information. The apolipoprotein E (APOE) ε4 allele is most studied but has shown differential effects within African ancestry compared to Caucasian. More candidate gene and genome-wide association studies are needed to relate to dementia phenotypes. Validated culture-sensitive cognitive tools not influenced by education and language differences are critically needed for implementation across multidisciplinary groupings such as the proposed African Dementia Consortium.

There are limited data from Africa on the burden and associations between pre-diabetes (pre-DM), diabetes mellitus (DM) and stroke occurrence in a region experiencing a profound rise in stroke burden.To characterize the associations between stroke and dysglycemic status among West Africans.The Stroke Investigative Research and Educational Network (SIREN) is a multicenter, case-control study involving 15 sites in Ghana and Nigeria. Cases include adults aged ≥18 years with clinical and radiological evidence of an acute stroke. Controls were age-and-gender matched stroke-free adults. Detailed evaluations for vascular factors were performed. Pre-diabetes was defined as HBA1c of 5.7%-6.4% or Fasting blood glucose (FBG) 5.6-7.0 mmol/L and DM as HBA1c6.5% or FBG7.0 mmol/L. We used conditional logistic regression to estimate adjusted odds ratios (aOR) with 95% Confidence Interval.Among 2,935 stroke cases the mean age was 60.0 ± 14.2 years with 55.2% being males. By glycemic status, 931 (31.7%) were euglycemic, 633 (21.6%) had Pre-diabetes and 1371 (46.7%) had DM. Of the age- and sex-matched stroke-free controls 69.2% were euglycemic, 13.3% had pre-DM and 17.5% had DM. Pre-DM [aOR (95% CI): 3.68(2.61-5.21)] and DM [4.29 (3.19-5.74)] were independently associated with stroke. The aOR of Pre-DM for ischemic stroke 3.06 (2.01-4.64)] was lower than 4.82 (3.37-6.89) for DM. However, the aOR of Pre-DM for hemorrhagic stroke 6.81 (95% CI: 3.29 - 14.08)] was higher than 3.36 (1.94-5.86) for DM. Furthermore, the aOR of pre-DM for ischemic stroke subtypes were 9.64 (1.30-71.57) for cardio-embolic stroke, 3.64 (1.80-7.34) for small-vessel occlusive disease and 4.63 (0.80-26.65) for large-vessel disease.Pre-DM is strongly and independently associated with stroke in Africans. Improving glycemic control through screening, healthy lifestyle and pharmacotherapy at a population level may be strategic in reducing the rising burden of stroke in Africa.

The prognostic implications of metabolic syndrome (METS) among African stroke patients are poorly understood. This study aimed to investigate the determinants of METS and its prognostic implications among Africans with newly diagnosed stroke in the SIREN study.We included stroke cases (adults aged18 years with CT/MRI confirmed stroke). The validated tools comprehensively evaluated vascular, lifestyle, and psychosocial factors. We used logistic regression to estimate adjusted odds ratios (OR) with 95% CIs for the association between METS and risk factors. We also computed the prediction power of the domain of covariates in a sequential manner using the area under the receiver operating curve (ROC) curve.Among 3998 stroke subjects enrolled in the study, 76.8% had METS by at least one of the clinical definitions. Factors associated with METS were age 50 years (OR- 1.46, CI-1.19-1.80), male gender (OR 4.06, CI- 3.28-5.03), income100USD (OR1.42, CI-1.17-1.71), stress (OR1.46, CI-1.14-1.87), family history of diabetes mellitus (OR1.38, CI-1.06-1.78), and cardiac disease (OR1.42, CI-1.18-1.65). Stroke severity was higher among those with METS (SLS = 5.8 ± 4.3) compared with those without METS (6.2 ± 4.5) at p = 0.037. METS was associated with higher odds (aOR 1.31, CI-1.08-1.58) of one-month fatality after adjusting for stroke severity, age 50 years, and average monthly income100USD.METS is very common among African stroke patients and is associated with stroke severity and worse one-month fatality. Lifestyle interventions may prevent METS and attenuate its impact on stroke occurrence and outcomes.

BACKGROUND: Post-stroke seizures (PSS) are associated with significant morbidity and mortality across the globe. There is a paucity of data on PSS in Africa. PURPOSE: To assess the frequency and factors associated with PSS by stroke types across 15 hospitals in Nigeria and Ghana. METHODS: We analyzed data on all stroke cases recruited into the Stroke Investigative Research and Educational Network (SIREN). We included adults aged ≥18 years with radiologically confirmed ischemic stroke (IS) or intracerebral hemorrhage (ICH). PSS were defined as acute symptomatic seizures occurring at stroke onset and/or during acute hospitalization up until discharge. We used logistic regression to estimate adjusted odds ratios (aOR) with 95% Confidence Interval. RESULTS: Among 3,344 stroke patients, 499 (14.9%) had PSS (95% CI: 13.7 – 16.2%). The mean duration of admission in days for those with PSS vs no PSS was 17.4 ± 28.6 vs 15.9 ± 24.7, p=0.72. There were 294(14.1%) PSS among 2091 ischemic strokes and 159(17.7%) among 897 with ICH, p=0.01. The factors associated with PSS occurrence were age

A 19-year-old man presents to the emergency room with migraine headaches seven days after a blow to the head during martial arts competition. His neurologic examination is normal. The patient wishe...

BACKGROUND: Laboratory - based studies of neurological disease patterns and mechanisms are sparse in sub- Saharan Africa. However, availability of human brain tissue resource depends on willingness towards brain donation. This study evaluated the level of willingness among outpatient clinic attendees in a Nigerian teaching hospital. METHODS: Under the auspices of the IBADAN Brain Bank Project, a 43 – item semi - structured interviewer – administered questionnaire was designed to evaluate knowledge, attitude, and beliefs of individuals attending Neurology, Psychiatry and Geriatrics Outpatient clinics regarding willingness to donate brain for research. Association between participants characteristics and willingness towards brain donation was investigated using logistic regression models. Analysis was conducted using Stata SE version 12.0. RESULTS: A total of 412 participants were interviewed. Their mean age was 46.3 (16.1) years. 229 (55.6%) were females and 92.5% had at least 6 years of formal education. Overall, 109 (26.7%) were willing to donate brains for research. In analyses adjusting for educational status, religion, ethnicity, marital status and family setting, male sex showed independent association with willingness towards brain donation OR (95% C.I) = 1.7 (1.08 – 2.69), p = 0.023. Participants suggested public engagement and education through mass media (including social media) and involvement of religious and community leaders as important interventions to improve awareness and willingness towards brain donation. CONCLUSION: The survey revealed low willingness among outpatient clinic attendees to donate brain for research, although men were more inclined to donate. It is imperative to institute public engagement and educational interventions in order to improve consent for brain donation for research.

Data on the burden and outcomes of recurrent strokes in sub-Saharan Africa are limited, impeding efforts at optimal recurrent stroke prevention.To assess the prevalence, risk factor profile, stroke types and mortality from recurrent strokes in Ghana and Nigeria.We analyzed data from 3553 stroke cases involved in the Stroke Investigative Research and Educational Networks (SIREN) study for proportion with recurrent strokes. Conditional logistic regression models were constructed to interrogate for risk factors of recurrent stroke compared with stroke-free controls. Generalized Linear models were used to assess correlates of recurrent strokes relative to index strokes.Among stroke cases, 335 (9.4%) were recurrent strokes, of which 79.9% were ischemic and 20.1% hemorrhagic. Those with recurrent stroke were significantly older than index stroke cases 62.2 ± 12.9 years vs 58.9 ± 14.0 years, p 0.01 respectively. Topmost risk factors associated with recurrent stroke were hypertension adjusted odds ratio 50.7 (95%CI: 6.6-392.7), dyslipidemia 2.8 (1.3-6.2), diabetes mellitus 4.0 (2.1-7.7) and family history of cardiovascular disease (CVD) 2.1 (1.1-4.2). The relative risk (95%CI) of factors associated with recurrent stroke vs index stroke were age 50 years (1.5: 1.1-2.0); Hausa ethnicity (1.5:1.1-2.1), Yoruba ethnicity with Akan as referent; table added salt (0.4:0.2-0.8) and current alcohol intake (0.6:0.4-0.9). In-patient mortality among those with recurrent stroke vs. primary stroke was 20.5% vs. 21.4%.Several modifiable lifestyle related factors may warrant additional emphasis as targets for reducing the burden of recurrent stroke in sub-Saharan Africa.

Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): National Institute of Health (NIH) OnBehalf SIREN as part of the H3 Africa Consortium Background Hypertension is the principal risk factor for stroke events in Sub-Saharan Africa (SSA). However, international evidence on the significance of physical inactivity as a critical driver of hypertension risk in SSA is sparse. Purpose This study assessed determinants of hypertension risk among a stroke-free population in Ghana and Nigeria. Methods Participants were 4,267 stroke-free individuals recruited in the Stroke Investigative Research and Education Network study from Nigeria and Ghana. Data on sociodemographic, lifestyle, cardiovascular risk and blood pressure were collected using standard protocols. Hypertension was defined as systolic blood pressure (SBP) ≥ 140mmHg or diastolic blood pressure (DBP) ≥ 90mmHg or a previous diagnosis or current use of antihypertensive medications. Odds ratio (OR) and 95% confidence interval (CI) for hypertension risk was estimated using logistic regression at P Results Mean age was 55.9 ± 14.7 and 1.8% were physically inactive. Mean SBP and DBP were 135.8 ± 24.2mmHg and 82.7 ± 14.3mmHg respectively, and 56.7% had hypertension. Factors associated with hypertension were physical inactivity (OR: 9.09; 95%CI: 4.03, 20.53), being diabetic (OR: 2.70; 95%CI: 1.91, 3.82), being older than 60years (OR: 2.22; 95%CI: 1.78, 2.77) and family history of cardiovascular diseases (OR: 2.02; 95%CI: 1.59, 2.56) and elevated waist circumference (OR: 1.01; 95%CI: 1.00, 1.02). Conclusion(s): Physical inactivity was the leading risk factor for hypertension in this population. Community-oriented interventions promoting physical activity should help in the control of hypertension among sub-Saharan African population.

Stroke is a leading cause of death and disability worldwide. The reasons for increased stroke burden in developing countries are inadequately controlled risk factors resulting from poor public awareness and inadequate infrastructure. Computed tomography and MRI are common neuroimaging modalities used to assess stroke with diffusion-weighted MRI, in particular, being the recommended choice for acute stroke imaging. However, access to these imaging modalities is primarily restricted to major cities and high-income groups. In the case of stroke, the time-window of treatment to limit the damage is of a few hours and needs a point-of-care diagnosis. A low-cost MR system typically achieved at the ultra-low- and very-low-field would meet the need for a geographically accessible and portable solution. We review studies focused on accessible stroke imaging and recent developments in MR methodologies, including hardware, to image at low fields. We hypothesize that in the absence of a formal, rapid stroke triaging system, the value of timely on-site delivery of the scanner to the stroke patient can be significant. To this end, we discuss multiple recent hardware and methods developments in the low-field regime. Our review suggests a compelling need to explore further the trade-offs between high signal, contrast, and accessibility at low fields in low-income communities. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 6.

Background This study is part of the Stroke Investigative Research and Educational Network (SIREN), the largest study of stroke patients in Africa to date, with computed tomography (CT) or magnetic resonance (MR) imaging data for each patient to confirm stroke. Prior imaging studies performed using high-field MR ( ≥ 1.5T) have shown that white matter hyperintensities (WMH), signs of microangiopathy in the subcortical brain, are correlated with many stroke risk factors as well as poor stroke outcomes. The aim of this study was the evaluation of MR images (0.3T–1.5T) from the SIREN study to determine associations between WMH volumes in West African patients and both stroke outcomes and stroke risk factors identified in the SIREN study. Materials and methods Brain MR images of 130 Western African stroke patients (age ​= ​57.87 ​± ​14.22) were processed through Lesion Segmentation Toolbox of the Statistical Parametric Mapping software to extract all areas of hyperintensity in the brain. WMH was separated from stroke lesion hyperintensity and WMH volume was computed and summed. A stepwise linear regression and multivariate analysis was performed between patients’ WMH volume and sociodemographic and clinical indices. Results Multivariate analysis showed that high WMH volume was statistically significantly positively correlated with age (β ​= ​0.44, p ​= ​0.001), waist/hip ratio (β ​= ​0.22, p ​= ​0.03), and platelet count (β ​= ​0.19, p ​= ​0.04) after controlling for head size in a Western African stroke population. Conclusion Associations between WMH and age and waist/hip ratio previously identified in Western countries were demonstrated for the first time in a resource-limited, homogeneous black African community using low-field MR scanners.

ObjectiveTo characterize risk factors for spontaneous intracerebral hemorrhage (sICH) occurrence and severity among West Africans.MethodsThe 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.ResultsOf 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).ConclusionsPopulation-level control of the dominant factors will substantially mitigate the burden of sICH in West Africa.

Background Stroke risk can be quantified using risk factors whose effect sizes vary by geography and race. No stroke risk assessment tool exists to estimate aggregate stroke risk for indigenous African. Objectives To develop Afrocentric risk-scoring models for stroke occurrence. Materials and Methods We evaluated 3533 radiologically confirmed West African stroke cases paired 1:1 with age-, and sex-matched stroke-free controls in the SIREN study. The 7,066 subjects were randomly split into a training and testing set at the ratio of 85:15. Conditional logistic regression models were constructed by including 17 putative factors linked to stroke occurrence using the training set. Significant risk factors were assigned constant and standardized statistical weights based on regression coefficients (β) to develop an additive risk scoring system on a scale of 0–100%. Using the testing set, Receiver Operating Characteristics (ROC) curves were constructed to obtain a total score to serve as cut-off to discriminate between cases and controls. We calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) at this cut-off. Results For stroke occurrence, we identified 15 traditional vascular factors. Cohen's kappa for validity was maximal at a total risk score of 56% using both statistical weighting approaches to risk quantification and in both datasets. The risk score had a predictive accuracy of 76% (95%CI: 74–79%), sensitivity of 80.3%, specificity of 63.0%, PPV of 68.5% and NPV of 76.2% in the test dataset. For ischemic strokes, 12 risk factors had predictive accuracy of 78% (95%CI: 74–81%). For hemorrhagic strokes, 7 factors had a predictive accuracy of 79% (95%CI: 73–84%). Conclusions The SIREN models quantify aggregate stroke risk in indigenous West Africans with good accuracy. Prospective studies are needed to validate this instrument for stroke prevention.

BACKGROUND: The burden of stroke in Africa is high. Understanding how age associates with major modifiable stroke risk factors could inform tailored demographic stroke prevention strategies. PURPOSE: To quantify the magnitude and direction of the effect sizes of key modifiable stroke risk factors according to three age groups: 65 years (elderly) in West Africa. METHODS: This was a case-control study involving 15 sites in Ghana and Nigeria. Cases included adults aged ≥18 years with CT/MRI scan-typed stroke. Controls were age-and gender-matched stroke-free adults. Detailed evaluations for vascular, lifestyle and psychosocial factors were performed. We estimated adjusted odds ratios (aOR) using conditional logistic regression and population attributable risk (PAR) with 95% Confidence Interval of vascular risk factors by age groups. RESULTS: Among 3553 stroke cases, 813 (22.9%) were young, 1441 (40.6%) were middle-aged and 1299 (36.6%) were elderly. Among the 5 co-shared risk factors, dyslipidemia with PAR and aOR (95%CI) of 62.20% (52.82–71.58) and 4.13 (2.64–6.46) was highest among the young age group; hypertension with PAR of 94.31% (91.82–96.80) and aOR of 28.93 (15.10–55.44) was highest among the middle-age group. Diabetes with PAR of 32.29% (27.52–37.05) and aOR of 3.49 (2.56–4.75); meat consumption with PAR of 42.34%(32.33–52.35) and aOR of 2.40 (1.76, 3.26); and non-consumption of green vegetables, PAR of 16.81%(12.02–21.60) and aOR of 2.23 (1.60–3.12) were highest among the elderly age group. However confidence intervals of risk estimates over-lapped across age groups. Additionally, among the young age group cigarette smoking, psychosocial stress and cardiac disease were independently associated with stroke. Furthermore, education, stress, physical inactivity and salt intake were associated with stroke in the middle-age group while cardiac disease was associated with stroke in the elderly age group. CONCLUSION: There is a differential influence of age on the associations of major risk factors with stroke in this West African cohort. Targeting modifiable factors predominant within an age group may be more effective as a stroke prevention strategy.

Background Annotation and Image Markup on ClearCanvas Enriched Stroke–phenotyping Software (ACCESS) is a novel stand-alone computer software application that allows the creation of simple standardized annotations for reporting brain images of all stroke types. We developed the ACCESS application and determined its inter-rater and intra-rater reliability in the Stroke Investigative Research and Educational Network (SIREN) study to assess its suitability for multicenter studies. Methods One hundred randomly selected stroke imaging reports from 5 SIREN sites were re-evaluated by 4 trained independent raters to determine the inter-rater reliability of the ACCESS (version 12.0) software for stroke phenotyping. To determine intra-rater reliability, 6 raters reviewed the same cases previously reported by them after a month of interval. Ischemic stroke was classified using the Oxfordshire Community Stroke Project (OCSP), Trial of Org 10172 in Acute Stroke Treatment (TOAST), and Atherosclerosis, Small-vessel disease, Cardiac source, Other cause (ASCO) protocols, while hemorrhagic stroke was classified using the Structural lesion, Medication, Amyloid angiopathy, Systemic disease, Hypertensive angiopathy and Undetermined (SMASH-U) protocol in ACCESS. Agreement among raters was measured with Cohen's kappa statistics. Results For primary stroke type, inter-rater agreement was .98 (95% confidence interval [CI], .94-1.00), while intra-rater agreement was 1.00 (95% CI, 1.00). For OCSP subtypes, inter-rater agreement was .97 (95% CI, .92-1.00) for the partial anterior circulation infarcts, .92 (95% CI, .76-1.00) for the total anterior circulation infarcts, and excellent for both lacunar infarcts and posterior circulation infarcts. Intra-rater agreement was .97 (.90-1.00), while inter-rater agreement was .93 (95% CI, .84-1.00) for TOAST subtypes. Inter-rater agreement ranged between .78 (cardioembolic) and .91 (large artery atherosclerotic) for ASCO subtypes and was .80 (95% CI, .56-1.00) for SMASH-U subtypes. Conclusion The ACCESS application facilitates a concordant and reproducible classification of stroke subtypes by multiple investigators, making it suitable for clinical use and multicenter research.

Introduction: The availability and utilization of MRI units across sub-Saharan Africa countries remain poor and its distribution is largely unknown. A cross-sectional survey was conducted to determine the distribution and utilization of MRI facilities across the West African sub-region. Methods: An interview and online search survey was conducted from September 2015 to September 2016, to determine the MRI facilities (Government/Public and Private) available in the West African sub-region. In Nigeria and Ghana, face-to-face interviews were conducted while for other West African countries, telephone interviews with radiologists and other health professionals as well as a Google online search were conducted to ascertain the distribution of the MRI facilities in the region. The number of MRI units in West Africa per million population was calculated and compared with other parts of the world from available published data. Results: Eighty-four MRI units serve a combined population of 372,551,411 in the West African sub-region at the time of this report. Nigeria accounted for more than two-thirds (58 (69%)) of the available units. Of these, 45 (77.6%) of the units were low-field strength systems. Ghana's 14 MRI units were fairly equally distributed between the private (57%) and the public sectors (43%). Ghana with 0.48 units/million population had the highest number of MRI units/ million population followed by Nigeria with 0.30 units/million population. Conclusion: Though there is an increase in the number of available MRI units in the West African sub region in the last decade, the numbers remain appallingly small for the population. Infrastructural and maintenance limitations constitute a major impediment to the use of high filed systems in the region. There may be need for greater cooperation between public and private enterprises for future improvement of MRI utilization in the region. Keywords: MRI, West Africa, survey, utilization, partnership