Browsing by Author "Gebregziabher M."

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African Ancestry, APOL1, candidate genes, CDKN2A/CDKN2B, HDAC9, small vessel disease, stroke, West Africa
(John Wiley & Sons Ltd, 2017) Akinyemi R.; Tiwari H. K.; Arnett D. K.; Ovbiagele B.; Irvin M. R.; Wahab K.; Sarfo F.; Srinivasasainagendra V.; Adeoye A.; Perry R. T.; Akpalu A.; Jenkins C.; Arulogun O.; Gebregziabher M.; Owolabi L.; Obiako R.; Sanya E.; Komolafe M.; Fawale M.; Adebayo P.; Osaigbovo G.; Sunmonu T.; Olowoyo P.; Chukwuonye I.; Obiabo Y.; Onoja A.; Akinyemi J.; Ogbole G.; Melikam S.; Saulson R.; Owolabi M.
Objective: Worldwide, the highest frequencies of APOL1-associated kidney variants are found in indigenous West Africans among whom small vessel disease (SVD) is chemic stroke is the most common stroke phenotype. The objective of this study was to investigate the association and effect sizes of 23 selected SNPs in 14 genes of relevance, including the APOL1 G1 variants, with the occurrence of SVD ischemic stroke among indigenous West African participants in the Stroke Investigative Research and Education Network (SIREN) Study. Materials and Methods: Cases were consecutively recruited consenting adults (aged 18 years or older) with neuroimaging—confirmed first clinical stroke. Stroke-free controls were ascertained using a locally validated version of the Questionnaire for Verifying Stroke-Free Status (QVSFS). Logistic regression models adjusting for known vascular risk factors were fitted to assess the associations of the 23 SNPs in rigorously phenotyped cases (N = 154) of SVD ischemic stroke and stroke-free (N = 483) controls. Results: Apolipoprotein L1 (APOL1) rs73885319 (OR = 1.52; CI: 1.09-2.13, P value = .013), rs2383207 in CDKN2A/CDKN2B (OR = 3.08; CI: 1.15-8.26, P – value = .026) and rs2107595 (OR = 1.70; CI: 1.12-2.60, P-value = .014) and rs28688791 (OR = 1.52; CI: 1.03-2.26, P-value = .036) in HDAC9 gene were associated with SVD stroke at 0.05 significance level. Polymorphisms in other genes did not show significant associations. Conclusion: This is the first report of a specific association of APOL1 with a stroke subtype. Further research is needed to confirm these initial findings and deepen understanding of the genetics of stroke in people of African ancestry with possible implications for other ancestries as all humans originated from Africa
Data resource profile: Cardiovascular H3Africa Innovation Resource (CHAIR)
(Oxford University Press, 2018) Owolabi M. O.; Akpa O. M.; Made F.; Adebamowo S. N.; Ojo A.; Adu D.; Motala A. A.; Mayosi B. M.; Ovbiagele B.; Adebamowo C.; Tayo B.; Rotimi C.; Akinyemi R.; Gebregziabher M.; Sarfo F.; Wahab K. W.
Differential impact of risk factors on stroke occurrence among men versus women in West Africa The SIREN Study
(American Heart Association, Inc., 2019) Akpalu A.; Gebregziabher M.; Ovbiagele B.; Sarfo F.; Iheonye H.; Akinyemi R.; Akpa O.; Tiwari H. K.; Arnett D.; Wahab K.; Lackland D.; Abiodun A.; Ogbole G.; Jenkins C.; Arulogun O.; Akpalu J.; Obiako R.; Olowoyo P.; Fawale M.; Komolafe M.; Osaigbovo G.; Obiabo Y.; Chukwuonye I.; Owolabi L.; Adebayo P.; Sunmonu T.; Owolabi M.
Background and Purpose—The interplay between sex and the dominant risk factors for stroke occurrence in sub-Saharan Africa has not been clearly delineated. We compared the effect sizes of risk factors of stroke by sex among West Africans. Methods—SIREN study (Stroke Investigative Research and Educational Networks) is a case-control study conducted at 15 sites in Ghana and Nigeria. Cases were adults aged >18 years with computerized tomography/magnetic resonance imaging confirmed stroke, and controls were age- and sex-matched stroke-free adults. Comprehensive evaluation for vascular, lifestyle, and psychosocial factors was performed using validated tools. We used conditional logistic regression to estimate odds ratios and reported risk factor specific and composite population attributable risks with 95% CIs. Results—Of the 2118 stroke cases, 1193 (56.3%) were males. The mean±SD age of males was 58.1±13.2 versus 60.15±14.53 years among females. Shared modifiable risk factors for stroke with adjusted odds ratios (95% CI) among females versus males, respectively, were hypertension [29.95 (12.49–71.77) versus 16.1 0(9.19–28.19)], dyslipidemia [2.08 (1.42–3.06) versus 1.83 (1.29–2.59)], diabetes mellitus [3.18 (2.11–4.78) versus 2.19 (1.53–3.15)], stress [2.34 (1.48–3.67) versus 1.61 (1.07–2.43)], and low consumption of green leafy vegetables [2.92 (1.89–4.50) versus 2.00 (1.33–3.00)]. However, salt intake and income were significantly different between males and females. Six modifiable factors had a combined population attributable risk of 99.1% (98.3%–99.6%) among females with 9 factors accounting for 97.2% (94.9%–98.7%) among males. Hemorrhagic stroke was more common among males (36.0%) than among females (27.6%), but stroke was less severe among males than females. Conclusions—Overall, risk factors for stroke occurrence are commonly shared by both sexes in West Africa favoring concerted interventions for stroke prevention in the region.
Dominant modifiable risk factors for stroke in Ghana and and Nigeria (SIREN): a case-control study
(Elsevier Ltd., 2018) Owolabi M. O.; Sarfo F. S.; Akinyemi R. O.; Gebregziabher M.; Akpa O.; Akpalu A.; Wahab K.; Obiako R.; Owolabi L.; Ovbiagele B.
Background Sub-Saharan Africa has the highest incidence, prevalence, and fatality from stroke globally. Yet, only little information about context-specific risk factors for prioritising interventions to reduce the stroke burden in sub-Saharan Africa is available. We aimed to identify and characterise the effect of the top modifiable risk factors for stroke in sub Saharan Africa. Methods The Stroke Investigative Research and Educational Network (SIREN) study is a multicentre, case-control study done at 15 sites in Nigeria and Ghana. Cases were adults (aged ≥18 years) with stroke confirmed by CT or MRI. Controls were age-matched and gender-matched stroke-free adults (aged ≥18 years) recruited from the communities in catchment areas of cases. Comprehensive assessment for vascular, lifestyle, and psychosocial factors was done using standard instruments. We used conditional logistic regression to estimate odds ratios (ORs) and population attributable risks (PARs) with 95% CIs. Findings Between Aug 28, 2014, and June 15, 2017, we enrolled 2118 case-control pairs (1192 [56%] men) with mean ages of 59•0 years (SD 13•8) for cases and 57•8 years (13•7) for controls. 1430 (68%) had ischaemic stoke, 682 (32%) had haemorrhagic stroke, and six x (<1%) had discrete ischaemic and haemorrhagic lesions. 98•2% (95% CI 97•2–99•0) of adjusted PAR of stroke was associated with 11 potentially modifiable risk factors with ORs and PARs in descending order of PAR of 19•36 (95% CI 12•11–30•93) and 90•8% (95% CI 87•9–93•7) for hypertension, 1•85 (1•44–2•38) and 35•8% (25•3–46•2) for dyslipidaemia, 1•59 (1•19–2•13) and 31•1% (13•3–48•9) for regular meat consumption, 1•48 (1•13–1•94) and 26•5% (12•9–40•2) for elevated waist-to-hip ratio, 2•58 (1•98–3•37) and 22•1% (17•8–26•4) for diabetes, 2•43 (1•81–3•26) and 18•2% (14•1–22•3) for low green leafy vegetable consumption, 1•89 (1•40–2•54) and 11•6% (6•6–16•7) for stress, 2•14 (1•34–3•43) and 5•3% (3•3–7•3) for added salt at the table, 1•65 (1•09–2•49) and 4•3% (0•6–7•9) for cardiac disease, 2•13 (1•12–4•05) and 2•4% (0•7–4•1) for physical inactivity, and 4•42 (1•75–11•16) and 2•3% (1•5–3•1) for current cigarette smoking. Ten of these factors were associated with ischaemic stroke and six with haemorrhagic stroke occurrence. Interpretation Implementation of interventions targeting these leading risk factors at the population level should substantially curtail the burden of stroke among Africans.
Echocardiographic abnormalities and determinants of 1-month outcome of stroke among West Africans in the SIREN Study
(American Heart Association, 2019) Adeoye A. M.; Ovbiagele B.; Akinyemi J. O.; Ogah O. S.; Akinyemi R.; Gebregziabher M.; Wahab K.; Fakunle A. G.; Akintunde A.; Adebayo O.; Aje A.; Tiwari H. K; Arnett D.; Agyekum F.; Appiah L. T.; Amusa G.; Olunuga T. O.; Akpa O.; Sarfo F. S.; Akpalu A.; Jenkins C.; Lackland D.
Background-—Little is known about the relationship between echocardiographic abnormalities and outcome among patients with acute stroke. We investigated the pattern and association of baseline echocardiographic variables with 1-month disability and mortality among patients with stroke in the SIREN (Stroke Investigative Research and Education Network) study. Methods and Results-—We enrolled and followed up consecutive 1020 adult patients with acute stroke with baseline transthoracic echocardiography from west Africa. To explore the relationship between echocardiographic variables and 1-month disability (using modified Rankin scale >3) and fatality, regression models were fitted. Relative risks were computed with 95% CIs. The participants comprised 60% men with a mean age of 59.2_14.6 years. Ischemic stroke was associated with smaller aortic root diameter (30.2 versus 32.5, P=0.018) and septal (16.8 versus 19.1, P<0.001) and posterior wall thickness at systole (18.9 versus 21.5, P=0.004). Over 90% of patients with stroke had abnormal left ventricular (LV) geometry with eccentric hypertrophy predominating (56.1%). Of 13 candidate variables investigated, only baseline abnormal LV geometry (concentric hypertrophy) was weakly associated with 1-month disability (unadjusted relative risk, 1.80; 95% CI, 0.97–5.73). Severe LV systolic dysfunction was significantly associated with increased 1-month mortality (unadjusted relative risk, 3.05; 95% CI, 1.36–6.83). Conclusions-—Nine of 10 patients with acute stroke had abnormal LV geometry and a third had systolic dysfunction. Severe LV systolic dysfunction was significantly associated with 1 month mortality. Larger studies are required to establish the independent effect and unravel predictive accuracy of this association
Exploring overlaps between the genomic and environmental determinants of LVH and stroke
(Elsevier Ltd, 2017) Adeoye A. M.; Ovbiagele B.; Kolo P.; Appiah L.; Ajek A.; Adebayo O.; Sarfo F.; Akinyemi J.; Adekunle G.; Agyekum F.; Shidali V.; Ogah O.; Lackland D.; Gebregziabher M.; Arnett D.; Tiwari H. K.; Akinyemi R.; Olagoke O. O.; Oguntade A. S.; Olunuga T.; Uwanruochi K.; Jenkins C.; Adadey P.; Iheonye H.; Owolabi L.; Obiako R.; Akinjopo S.; Armstrong K.; Akpalu A.; Fakunle A.; Saulson R.; Aridegbe M.; Olowoyo P.; Osaigbovo G.; Akpa O.
Background: Whether left ventricular hypertrophy (LVH) is determined by similar genomic and environmental risk factors with stroke, or is simply an intermediate stroke marker, is unknown. Objectives: We present a research plan and preliminary findings to explore the overlap in the genomic and environmental determinants of LVH and stroke among Africans participating in the SIREN (Stroke Investigative Research and Education Network) study. Methods: SIREN is a transnational, multicenter study involving acute stroke patients and age-, ethnicity-, and sex-matched control subjects recruited from 9 sites in Ghana and Nigeria. Genomic and environmental risk factors and other relevant phenotypes for stroke and LVH are being collected and compared using standard techniques. Results: This preliminary analysis included only 725 stroke patients (mean age 59.1 13.2 years; 54.3% male). Fifty-five percent of the stroke subjects had LVH with greater proportion among women (51.6% vs. 48.4%; p < 0.001). Those with LVH were younger (57.9 12.8 vs. 60.6 13.4; p ¼ 0.006) and had higher mean systolic and diastolic blood pressure (167.1/99.5 mm Hg vs 151.7/90.6 mm Hg; p < 0.001). Uncontrolled blood pressure at presentation was prevalent in subjects with LVH (76.2% vs. 57.7%; p < 0.001). Significant independent predictors of LVH were age 90 mm Hg (AOR: 2.10; 95% CI: 1.39 to 3.19; p < 0.001). Conclusions: The prevalence of LVH was high among stroke patients especially the younger ones, suggesting a genetic component to LVH. Hypertension was a major modifiable risk factor for stroke as well as LVH. It is envisaged that the SIREN project will elucidate polygenic overlap (if present) between LVH and stroke among Africans, thereby defining the role of LVH as a putative intermediate cardiovascular phenotype and therapeutic target to inform interventions to reduce stroke risk in populations of African ancestry
Multilingual Validation of the Questionnaire for Verifying Stroke-Free Status in West Africa
(Lippincott Williams & Wilkins, 2016) Sarfo F.; Gebregziabher M.; Ovbiagele B.; Akinyemi R.; Owolabi L.; Obiako R.; Akpa O.; Armstrong K.; Akpalu A.; Adamu S.; Obese V.; Boa-Antwi N.; Appiah L.; Arulogun O.; Mensah Y.; Adeoye A.; Tosin A.; Adeleye O.; Tabi-Ajayi E.; Phillip I.; Sani A.; Isah S.; Tabari N.; Mande A.; Agunloye A.; Ogbole G.; Akinyemi J.; Laryea R.; Melikam S.; Uvere E.; Adekunle G.; Kehinde S.; Azuh P.; Dambatta A.; Ishaq N.; Saulson R.; Arnett D.; Tiwari H.; Jenkins C.; Lackland D.; Owolabi M.
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.
Randomized trial of an intervention to improve blood pressure control in stroke survivors
(American Heart Association, Inc., 2020) Owolabi M. O.; Gebregziabher M.; Akinyemi R. O.; Akinyemi J. O.; Akpa O.; Olaniyan O.; Salako B. L.; Arulogun O.; Tagge R.; Uvere E.; Fakunle A.; Ovbiagele B.
BACKGROUND: We conducted the first-of-its kind randomized stroke trial in Africa to test whether a THRIVES (Tailored Hospital-based Risk reduction to Impede Vascular Events after Stroke) intervention improved blood pressure (BP) control among patients with stroke. METHODS AND RESULTS: Intervention comprised a patient global risk factor control report card, personalized phone text-messaging, and educational video. Four hundred patients recruited from 4 distinct medical facilities in Nigeria, aged ≥18 years with stroke-onset within one-year, were randomized to THRIVES intervention and control group. The control group also received text messages, and both groups received modest financial incentives. The primary outcome was mean change in systolic BP (SBP) at 12 months. There were 36.5% females, 72.3% with ischemic stroke; mean age was 57.2±11.7 years; 93.5% had hypertension and mean SBP was 138.33 (23.64) mmHg. At 12 months, there was no significant difference in SBP reduction from baseline in the THRIVES versus control group (2.32 versus 2.01 mmHg, P=0.82). In an exploratory analysis of subjects with baseline BP >140/90 mmHg (n=168), THRIVES showed a significant mean SBP (diastolic BP) decrease of 11.7 (7.0) mmHg while control group showed a significant mean SBP (diastolic BP) decrease of 11.2 (7.9) mmHg at 12 months. CONCLUSIONS: THRIVES intervention did not significantly reduce SBP compared with controls. However, there was similar significant decrease in mean BP in both treatment arms in the subgroup with baseline hypertension. As text-messaging and a modest financial incentive were the common elements between both treatment arms, further research is required to establish whether these measures alone can improve BP control among stroke survivors
Short-term pilot feasibility study of a nurse-led intervention to improve blood pressure control after stroke in Nigeria
(Elsevier B.V, 2017) Wahab K. W.; Owolabi M.; Akinyemi R.; Jenkins C.; Arulogun O.; Akpa O.; Gebregziabher M.; Uvere E.; Saulson R.; Ovbiagele B.
Background: Given the paucity of neurologists in Sub-Saharan Africa (SSA), task-shifting post-stroke care to nurses could be a viable avenue for enhancing post-stroke outcomes. This pilot study assessed the feasibility and short-term impact of a nurse-led intervention to manage blood pressure (BP) control in recent stroke survivors in Nigeria. Methods: A randomized pilot trial allocated patients within one month of an index stroke from two participating hospitals in Nigeria to either nurse-led group clinic or standard care for 14 days. Key study endpoints were successful execution of the protocol, subject retention, and short-term BP effects. Results: There were no significant differences between the intervention (n = 17) and control (n = 18) groups at baseline. At the post-intervention clinic, patient retention rate was 100%. In the intervention group, both the systolic and diastolic BPs measured at home were lower than the clinic BPs post-interven tion (127 ± 12.88/78.13 ± 19.26 mmHg versus 137.50 ± 23.05/84.06 ± 9.67 mmHg; p = 0.05). However, there was no significant change in clinic blood pressure (BP) recordings in both the intervention and control groups. Conclusion: It is possible to initiate a nurse-led group clinic intervention to address BP management among stroke survivors in SSA with good early retention of participants. A larger and longer-term trial is being planned.
Stroke Among Young West Africans Evidence From the SIREN (Stroke Investigative Research and Educational Network) Large Multisite Case–Control Study.
(American Heart Association, Inc., 2019) Sarfo F. S.; Ovbiagele B.; Gebregziabher M.; Wahab K.; Akinyemi R. O.; Akpalu A.; Akpa O.; Obiako R.; Owolabi L.; Jenkins C.; Owolabi M. O.
Background and purpose: Stroke in lower and middle-income countries affects a young and productive age group. Data on factors associated with stroke in the young are sorely lacking from lower and middle-income countries. Our objective is to characterize the nature of stroke and its risk factors among young West Africans aged <50 years old. Methods: The SIREN (Stroke Investigative Research and Educational Network) is a multicenter, case-control study involving 15 sites in Nigeria and Ghana. Cases included adults aged ≥18 years with computed tomography/magnetic resonance imaging-confirmed stroke. Controls were age-and gender-matched stroke-free adults recruited from the communities in catchment areas of cases. Comprehensive evaluation for vascular, lifestyle, and psychosocial factors was performed. We used conditional logistic regression to estimate odds ratios and population attributable risks with 95% confidence intervals. Results: Five hundred fifteen (24.3%) out of 2118 cases enrolled were <50 years old. Among subjects <50 years old, hemorrhagic stroke proportion was 270 (52.5%) versus 245 (47.5%) for ischemic strokes. Etiologic subtypes of ischemic strokes included large artery atherosclerosis (40.0%), small vessel disease (28.6%), cardioembolism (11.0%), and undetermined (20.4%). Hypertension (91.7%), structural lesions (3.4%), and others (4.9%) were causally associated with hemorrhagic stroke. Six topmost modifiable factors associated with stroke in descending order of population attributable risk (95% confidence interval) were hypertension: 88.7% (82.5%-94.8%), dyslipidemia: 48.2% (30.6%-65.9%), diabetes mellitus: 22.6% (18.7%-26.5%), low green vegetable consumption: 18.2% (-6.8%-43.2%), stress: 14.5% (4.9%-24.1%), and cardiac disease: 8.4% (5.8%-11.1%). Conclusions: The high and rising burden of stroke among young Africans should be curtailed via aggressive, population-wide vascular risk factor control.
The epidemiology of stroke in Africa: A systematic review of existing methods and new approaches
(Wiley Periodicals, Inc., 2017) Owolabi M.; Olowoyo P.; Popoola F.; Lackland D.; Jenkins C.; Arulogun O.; Akinyemi R.; Akinyemi O.; Akpa O.; Olaniyan O.; Uvere E.; Kehinde I.; Selassie A.; Gebregziabher M.; Tagge R.; Ovbiagele B.
Accurate epidemiological surveillance of the burden of stroke is direly needed to facilitate the development and evaluation of effective interventions in Africa. The authors therefore conducted a systematic review of the methodology of stroke epidemiological studies conducted in Africa from 1970 to 2017 using gold standard criteria obtained from landmark epidemiological publications. Of 1330 articles extracted, only 50 articles were eligible for review grouped under incidence, prevalence, case-fatality, health-related quality of life, and disability-adjusted life-years studies. Because of various challenges, no study fulfilled the criteria for an excellent stroke incidence study. The relatively few stroke epidemiology studies in Africa have significant methodological flaws. Innovative approaches leveraging available information and communication technology infrastructure are recommended to facilitate rigorous epidemiological studies for accurate stroke surveillance in Africa.