Risk Factor Characterization of Ischemic Stroke Subtypes Among West Africans.

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.

Differential associations between pre-diabetes, diabetes and stroke occurrence among West Africans.

BACKGROUND: 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. PURPOSE: To characterize the associations between stroke and dysglycemic status among West Africans. METHODS: 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 HBA1c >6.5% or FBG>7.0 mmol/L. We used conditional logistic regression to estimate adjusted odds ratios (aOR) with 95% Confidence Interval. RESULTS: 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. CONCLUSION: 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.

A Novel Afrocentric Stroke Risk Assessment Score: Models from the Siren Study.

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 (ß) 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.

Development and Reliability of a User-Friendly Multicenter Phenotyping Application for Hemorrhagic and Ischemic Stroke.

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.

Multilingual Validation of the Questionnaire for Verifying Stroke-Free Status in West Africa.

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 on-going 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 neuroimaging (gold standard). Relative performance of QVSFS without and with pictures of stroke symptoms (pictograms) was assessed using sensitivity, specificity, positive predictive value, and negative predictive value. 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, whereas of 219 without stroke 87% were determined to be stroke-free by QVSFS. Negative predictive value of the QVSFS across the 3 languages was 0.97 (range, 0.93-1.00), sensitivity, specificity, and positive predictive value were 0.98, 0.82, and 0.80, respectively. Agreement between the questionnaire with and without the pictogram was excellent/strong with Cohen k=0.92. CONCLUSIONS: QVSFS is a valid tool for verifying stroke-free status across culturally diverse populations in West Africa.

Phenotyping Stroke in Sub-Saharan Africa: Stroke Investigative Research and Education Network (SIREN) Phenomics Protocol.

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.

Exploring carotid sonographic parameters associated with stroke risk among hypertensive stroke patients compared to hypertensive controls.

OBJECTIVES: Globally, and particularly in low- and middle-income countries, the prevalence of hypertension is increasing with a consequent rise in the burden of stroke. There is a need to identify biomarkers of stroke, which can be used to design stroke prevention programs in these populations. Sonography is an affordable and widely available imaging modality that is ideal for resource-poor countries. We conducted a case-control study to identify carotid sonographic parameters that may be associated with stroke risk among hypertensive patients. METHODS: Selected demographic, clinical, and laboratory characteristics were collected from 135 consecutive African hypertensive stroke patients and compared with 117 age and sex-matched hypertensive patients with no clinical evidence of stroke, transient ischemic attacks, or ischemic heart disease (controls). The luminal diameter, intima-media thickness, peak systolic velocity (PSV), and end-diastolic velocity (EDV) of the common and internal carotid arteries were measured in all participants, and other carotid parameters, including pulsatility and resistive indices, were derived. Univariate, bivariate, and multivariate analyses were performed RESULTS: Among hypertensive patients, carotid parameters significantly (P < .05) associated with stroke included a higher diameter and intima-media thickness as well as a lower PSV and EDV in the common carotid and proximal internal carotid arteries. However, the diameter (>6.3 mm; adjusted odds ratio [OR], 8.91; 95% confidence interval [CI], 2.18-36.34; P = .002) and EDV (>21 cm/s; adjusted OR, 0.15; 95% CI, 0.03-0.71; P = .017) of the common carotid artery were the only parameters associated with stroke in multivariate analysis. CONCLUSIONS: Among hypertensive patients, the common carotid artery diameter and EDV are significantly associated with stroke risk. These findings have implications for development and evaluation of stroke prevention programs.

The relationship of flow velocities to vessel diameters differs between extracranial carotid and vertebral arteries of stroke patients.

BACKGROUND: Chronic changes in flow rate through arteries produce adjustment of arterial diameters. We compared the relationship between flow velocity and diameter in the carotid and in the vertebral arteries of stroke patients. METHODS: Using triplex ultrasonography, the internal diameter and flow velocities of the common carotid, internal carotid, and vertebral arteries of 176 consecutive stroke patients were measured. Correlations were examined with Pearson's statistics at an alpha level of 0.05. RESULTS: Mean age of the patients was 59.3 ± 12 years, and 66% had cerebral infarcts. Diameter and blood flow velocities showed significant negative correlations (-0.115 ≥ r ≥ -0.382) in the carotid arteries on both sides, but positive correlations (0.211 ≤ r ≤ 0.320) in the vertebral arteries, even after controlling for age, gender, and blood pressure. CONCLUSIONS: Our study demonstrated different diameter/flow relationships in the carotid and the vertebral arteries of stroke patients, which may suggest pathologic changes in the adaptive processes governing vessel diameter and growth, especially in the carotid arteries.

Novel functional insights into ischemic stroke biology provided by the first genome-wide association study of stroke in indigenous Africans.

BACKGROUND: African ancestry populations have the highest burden of stroke worldwide, yet the genetic basis of stroke in these populations is obscure. The Stroke Investigative Research and Educational Network (SIREN) is a multicenter study involving 16 sites in West Africa. We conducted the first-ever genome-wide association study (GWAS) of stroke in indigenous Africans. METHODS: Cases were consecutively recruited consenting adults (aged > 18 years) with neuroimaging-confirmed ischemic stroke. Stroke-free controls were ascertained using a locally validated Questionnaire for Verifying Stroke-Free Status. DNA genotyping with the H3Africa array was performed, and following initial quality control, GWAS datasets were imputed into the NIH Trans-Omics for Precision Medicine (TOPMed) release2 from BioData Catalyst. Furthermore, we performed fine-mapping, trans-ethnic meta-analysis, and in silico functional characterization to identify likely causal variants with a functional interpretation. RESULTS: We observed genome-wide significant (P-value < 5.0E-8) SNPs associations near AADACL2 and miRNA (MIR5186) genes in chromosome 3 after adjusting for hypertension, diabetes, dyslipidemia, and cardiac status in the base model as covariates. SNPs near the miRNA (MIR4458) gene in chromosome 5 were also associated with stroke (P-value < 1.0E-6). The putative genes near AADACL2, MIR5186, and MIR4458 genes were protective and novel. SNPs associations with stroke in chromosome 2 were more than 77 kb from the closest gene LINC01854 and SNPs in chromosome 7 were more than 116 kb to the closest gene LINC01446 (P-value < 1.0E-6). In addition, we observed SNPs in genes STXBP5-AS1 (chromosome 6), GALTN9 (chromosome 12), FANCA (chromosome 16), and DLGAP1 (chromosome 18) (P-value < 1.0E-6). Both genomic regions near genes AADACL2 and MIR4458 remained significant following fine mapping. CONCLUSIONS: Our findings identify potential roles of regulatory miRNA, intergenic non-coding DNA, and intronic non-coding RNA in the biology of ischemic stroke. These findings reveal new molecular targets that promise to help close the current gaps in accurate African ancestry-based genetic stroke's risk prediction and development of new targeted interventions to prevent or treat stroke.

Clinical and neuroimaging factors associated with 30-day fatality among indigenous West Africans with spontaneous intracerebral hemorrhage.

BACKGROUND: Spontaneous intracerebral hemorrhage (ICH) is associated with a high case fatality rate in resource-limited settings. The independent predictors of poor outcome after ICH in sub-Saharan Africa remains to be characterized in large epidemiological studies. We aimed to determine factors associated with 30-day fatality among West African patients with ICH. METHODS: The Stroke Investigative Research and Educational Network (SIREN) study is a multicentre, case-control study conducted at 15 sites in Nigeria and Ghana. Adults aged ≥18 years with spontaneous ICH confirmed with neuroimaging. Demographic, cardiovascular risk factors, clinical features and neuroimaging markers of severity were assessed. The independent risk factors for 30-day mortality were determined using a multivariate logistic regression analysis with an adjusted odds ratio (OR) and 95% confidence interval (CI). RESULTS: Among 964 patients with ICH, 590 (61.2%) were males with a mean age (SD) of 54.3(13.6) years and a case fatality of 34.3%. Factors associated with 30-day mortality among ICH patients include: Elevated mean National Institute of Health Stroke Scale(mNIHSS);(OR 1.06; 95% CI 1.02-1.11), aspiration pneumonitis; (OR 7.17; 95% CI 2.82-18.24), ICH volume > 30mls; OR 2.68; 95% CI 1.02-7.00)) low consumption of leafy vegetables (OR 0.36; 95% CI 0.15-0.85). CONCLUSION: This study identified risk and protective factors associated with 30-day mortality among West Africans with spontaneous ICH. These factors should be further investigated in other populations in Africa to enable the development of ICH mortality predictions models among indigenous Africans.

Sociodemographic and behavioural risk factors for obesity among community-dwelling older adults in Ghana and Nigeria: A secondary analysis of data from the SIREN study.

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 < 0.05. 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.

Dietary patterns associated with stroke among West Africans: A case-control study.

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 < 0.05). 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.

Patient-level and system-level determinants of stroke fatality across 16 large hospitals in Ghana and Nigeria: a prospective cohort study.

BACKGROUND: Every minute, six indigenous Africans develop new strokes. Patient-level and system-level contributors to early stroke fatality in this region are yet to be delineated. We aimed to identify and quantify the contributions of patient-level and system-level determinants of inpatient stroke fatality across 16 hospitals in Ghana and Nigeria. METHODS: The Stroke Investigative Research and Educational Network (SIREN) is a multicentre study involving 16 sites in Ghana and Nigeria. Cases include adults (aged ≥18 years) with clinical and radiological evidence of an acute stroke. Data on stroke services and resources available at each study site were collected and analysed as system-level factors. A host of demographic and clinical variables of cases were analysed as patient-level factors. A mixed effect log-binomial model including both patient-level and system-level covariates was fitted. Results are presented as adjusted risk ratios (aRRs) with respective 95% CIs. FINDINGS: Overall, 814 (21·8%) of the 3739 patients admitted with stroke died as inpatients: 476 (18·1%) of 2635 with ischaemic stroke and 338 (30·6%) of 1104 with intracerebral haemorrhage. The variability in the odds of stroke fatality that could be attributed to the system-level factors across study sites assessed using model intracluster correlation coefficient was substantial at 7·3% (above a 5% threshold). Stroke units were available at only five of 16 centres. The aRRs of six patient-level factors associated with stroke fatality were: low vegetable consumption, 1·19 (95% CI 1·07-1·33); systolic blood pressure, 1·02 (1·01-1·04) for each 10 mm Hg rise; stroke lesion volume more than 30 cm3, 1·48 (1·22-1·79); National Institutes of Health Stroke Scale (NIHSS) score, 1·20 (1·13-1·26) for each 5-unit rise; elevated intracranial pressure, 1·75 (1·31-2·33); and aspiration pneumonia, 1·79 (1·16-2·77). INTERPRETATION: Studies are needed to assess the efficacy of interventions targeting patient-level factors such as aspiration pneumonia in reducing acute stroke fatality in this region. Policy directives to improve stroke unit access are warranted. FUNDING: US National Institutes of Health. TRANSLATIONS: For the Twi, Yoruba and Hausa translations of the abstract see Supplementary Materials section.

Determinants of metabolic syndrome and its prognostic implications among stroke patients in Africa: Findings from the Stroke Investigative Research and Educational Network (SIREN) study.

BACKGROUND: 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. METHODS: We included stroke cases (adults aged >18 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. RESULTS: 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), income >100USD (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 income >100USD. CONCLUSION: 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.

Secondhand smoke exposure is independently associated with stroke among non-smoking adults in West Africa.

BACKGROUND: Stroke is a leading cause of disability and mortality worldwide, but little is known about the contribution of secondhand smoke exposure (SHSE) to stroke epidemiology among indigenous Africans. OBJECTIVE: To evaluate the association of SHSE with stroke among indigenous Africans. METHODS: We analyzed the relationship of SHSE with stroke among 2990 case-control pairs of adults who had never smoked (identified in the SIREN study) using conditional logistic regression at a two-sided P < 0.05. RESULTS: Multivariable-adjusted odds ratio and 95% confidence interval; 1.25 (1.04, 1.50; P = 0.02) revealed SHSE was positively associated with stroke independent of stroke subtypes. CONCLUSION: Culturally relevant primary prevention strategies targeted at SHSE might be promising in preventing stroke among Africans.

Carotid and Vertebral Atherosclerosis in West African Stroke Patients: Findings from the Stroke Investigative Research and Education Network.

Background: We evaluated the characteristics of carotid and vertebral atherosclerosis in indigenous West Africans with stroke. Methodology: Of the 3778stroke patients recruited between 01/2014 and 08/2017, 1070 (28.3%) received carotid and vertebral artery evaluation with B-mode Ultrasound. Carotid and vertebral intima-media thickness (IMT) using multiple site technique were measured bilaterally and plaque frequency was determined. Descriptive and comparative analyses between stroke types and vessels were carried out. Results: There were 809 (75.6%) patients with ischemic stroke. The prevalence of intima-media thickening in the study population was 84.0% (898/1070) [95% CI: 81.7-86.1], being higher in the ischemic stroke (688/809, 85.0%) [95% CI: 82.4-87.3] than in the hemorrhagic stroke group (211/261, 80.8%) [95% CI: 75.6-85.2]. Overall prevalence of plaques which was 26.1% [95% CI: 23.5-28.8], was found also to be higher in ischemic than hemorrhagic stroke (29.8%[95% CI: 26.7-33.0] vs. 14.6% [95% CI: 10.8-19.4], p < 0.05). The mean IMT (carotids: 2.01+1.33 mm; vertebrals: 0.96+0.54mm, p<0.001) and prevalence of plaques (carotids: 8.8%; vertebrals: 1.7%,p<0.001) were higher in carotid than vertebral arteries. Age, hypertension, level of formal education, history of smoking, average monthly income, and family histories of hypertension and stroke were associated with intima-media thickening in the carotids (all p< 0.05) in the ischemic stroke patients while family history of hypertension, diabetes mellitus, and level of formal education were independently associated with intima-media thickening in the carotids (all p< 0.05) in the hemorrhagic stroke patients. No CVRF showed an independent association with the presence of plaque in the carotid and vertebral arteries both stroke types. Conclusions: One off our stroke patients in our cohort had atherosclerotic plaques, with ischemic patients being twice as likely to have this burden compared to hemorrhagic patients, and carotid atherosclerosis being five times as frequent as vertebral atherosclerosis.

The role of routine post-natal abdominal ultrasound for newborns in a resource-poor setting: a longitudinal study.

BACKGROUND: Neonatal abdominal ultrasound is usually performed in Nigeria to investigate neonatal symptoms rather than as a follow up to evaluate fetal abnormalities which were detected on prenatal ultrasound. The role of routine obstetric ultrasonography in the monitoring of pregnancy and identification of fetal malformations has partly contributed to lowering of fetal mortality rates. In Nigeria which has a high maternal and fetal mortality rate, many pregnant women do not have ante-natal care and not infrequently, women also deliver their babies at home and only bring the newborns to the clinics for immunization. Even when performed, most routine obstetric scans are not targeted towards the detection of fetal abnormalities.The aim of the present study is to evaluate the benefit of routinely performing abdominal scans on newborns with a view to detecting possible abnormalities which may have been missed ante-natally. METHODS: This was a longitudinal study of 202 consecutive, apparently normal newborns. Routine clinical examination and abdominal ultrasound scans were performed on the babies by their mother's bedside, before discharge. Neonates with abnormal initial scans had follow-up scans. RESULTS: There were 108 males and 94 females. There were 12 (5.9%) abnormal scans seen in five male and seven female neonates. Eleven of the twelve abnormalities were in the kidneys, six on the left and five on the right. Three of the four major renal anomalies- absent kidney, ectopic/pelvic kidney and two cases of severe hydronephrosis were however on the left side. There was one suprarenal abnormality on the right suspected to be a possible infected adrenal haemorrage. Nine of the abnormal cases reported for follow- up and of these, two cases had persistent severe abnormalities. CONCLUSIONS: This study demonstrated a 5.9% incidence of genito urinary anomalies on routine neonatal abdominal ultrasound in this small population. Routine obstetric USS is very useful but inadequate availability of skilled personnel and cost implications create great challenges in poor resource settings like Nigeria. However, awareness should be created so that parents who can afford such investigations can make informed decisions.

Unraveling the risk factors for spontaneous intracerebral hemorrhage among 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.

Unintentional injury outcomes secondary to pedestrian traffic crashes: a descriptive analysis from a major medical center.

INTRODUCTION: An environment in which traffic regulations are not strictly enforced often is characterized by carnage from motor vehicular crashes resulting in severe injuries with unacceptably high mortality. The descriptive demographics and injury characteristics of pedestrian road crash victims presenting to a tertiary medical center in southwestern Nigeria are presented in order to provide baseline epidemiology as a first step in determining areas of potential mitigation for care of unintentional injuries. METHODS: Consecutive pedestrian road traffic crash patients treated in the Accident and Emergency Department of a tertiary hospital were prospectively reviewed from March 2007 to February 2008 to determine baseline demographics and clinical outcomes. RESULTS: A total of 184 patients with a mean value of the ages of 31.4 years were studied; 27% of the patients were <11 years of age. The male to female ratio was 1.6:1. Fifty-four percent of the victims were struck by automobiles and 29% were struck by motorcycles. Sixty-five percent were struck while crossing common thoroughfares. Head injury was sustained in 61% of patients. The mortality rate was 31.0% (n = 57). The clinical course leading to death showed 22.8% of the patients who died initially experienced hemorrhagic shock, 17.5% suffered a severe head injury, and 17.5% suffered aspiration. Autopsy confirmed brainstem herniation in 28.1% of the patients who died. The average interval between injury and death was 5.5 +/-13.6 days (range: 0-77 days). In this setting, three out of every ten patients experiencing pedestrian vehicular trauma will die before leaving the hospital. The elderly are most at risk, with two-thirds of victims dying from injuries sustained. CONCLUSIONS: This raises serious questions about the prehospital- and hospital-based emergency services for vehicular road crash victims in this environment, and confirms the World Health Organization findings that Africa has the highest rate overall for unintentional injury deaths. A system-wide program must be put in place that addresses proven prevention measures across all sectors of the community.

Abdominal ultrasonography in HIV/AIDS patients in southwestern Nigeria.

BACKGROUND: Though the major target of the HIV-virus is the immune system, the frequency of abdominal disorders in HIV/AIDS patients has been reported to be second only to pulmonary disease. These abdominal manifestations may be on the increase as the use of antiretroviral therapy has increased life expectancy and improved quality of life. Ultrasonography is an easy to perform, non invasive, inexpensive and safe imaging technique that is invaluable in Africa where AIDS is most prevalent and where sophisticated diagnostic tools are not readily available. PURPOSE: To describe the findings and evaluate the clinical utility of abdominal ultrasonography in HIV/AIDS patients in Ibadan, Nigeria METHODS: A Prospective evaluation of the abdominal ultrasonography of 391 HIV-positive patients as well as 391 age and sex-matched HIV-negative patients were carried out at the University College Hospital, Ibadan. RESULTS: Of the 391 cases studied, 260 (66.5%) were females; the mean age was 38.02 years, (range 15-66 years). The disease was most prevalent in the 4th decade with an incidence of 40.4%. Compared with the HIV-negative individuals, the HIV+ group of patients had a significantly higher proportion of splenomegaly (13.5% vs. 7.7%; p < 0.01), lymphadenopathy (2.0% vs. 1.3%; p < 0.70), and renal abnormalities (8.4% vs. 3.8%; p < 0.02). There were no differences in hepatic and pancreatic abnormalities between the HIV+ and HIV- groups. There were significantly fewer gallstones in the HIV+ group (1.4% vs. 5.1%; p < 0.01). CONCLUSION: AIDS is a multi-systemic disease and its demographic and clinical pattern remains the same globally. Ultrasonography is optimally suited for its clinical management especially in Africa. Its accuracy and sensitivity may be much improved with clinico-pathologic correlation which may not be readily available in developing countries; further studies may provide this much needed diagnostic algorithms.