Unraveling the risk factors for spontaneous intracerebral hemorrhage among West Africans

A systematic review of the epidemiology and the public health implications of stroke in Sub-Saharan Africa

BACKGROUND

With approximately 11 million strokes occurring annually worldwide, and over 6.5 million deaths annually, stroke has made its place as one of the major killers in the world. Although developing countries make up more than 4/5 of the global stroke burden, well-grounded information on stroke epidemiology remains lacking there.

AIMS

This systematic review study aimed to provide a synthesis of studies on the incidence and prevalence of stroke among adults in sub-Saharan Africa (SSA), subsequently deduce the associated risk factors and public health implications (mortality rates and economic costs) of the disease on the population of this region.

METHODS

A systematic review of studies carried out in the region and published on PUBMED. Eligibility criteria were established using the PEO (Population/Patient, Exposure, Outcome) format. Research articles investigating either (or all) of the following: ischemic or haemorrhagic stroke, incidence, prevalence, and risk factors of stroke in adults (≥ 18 years old), in at least one region of SSA were included. Exclusion criteria comprised studies involving populations younger than 18 years old, research conducted outside the designated research region, and articles inaccessible in full text. The PRISMA guidelines were used for the search strategy.

RESULTS

Fifty-two studies were included review. Among them, over 11 studies investigated the prevalence of the disease. Some older studies within the continent (Nigeria, 2011) showed a prevalence of 1.3 per 100 while more recent studies (Zambia, 2021) showed a prevalence of 4.3 per 1000. The highest prevalence noted in this region was in Madagascar (2017) with 48.17 per 100, while the lowest was recorded in (Zimbabwe, 2017) with 0.61 per 100. The study in Tanzania showed a crude incidence of 94·5 per 100 000 (76·0-115·0) while the study in Ghana in 2018 showed an incidence of 14.19 events per 1000 person-years [10.77-18.38]. The identified risk factors included hypertension, diabetes, smoking, alcohol consumption, physical inactivity, poor diets (more salt, less vegetables), dyslipidaemia, HIV/AIDS co-infection, heart disease (cardiomyopathies, cardiac arrhythmias), obesity, previous stroke and/or family history of stroke. Over 21 studies investigated the mortality rates due to stroke in SSA, with most of the studies being in West Africa. These studies revealed mortality rates as high as 43.3% in Ghana, and as low as 10.9% in Cameroon. Few studies reported on the economic costs of stroke in the region; two in Benin, two in Nigeria and one in Tanzania.

CONCLUSION

The increasing incidence/prevalence, lifestyle factors and interactions with other diseases, including major communicable diseases, stroke is becoming a pressing public health problem for SSA. Reducing the incidence of stroke in Africa will surely lower mortality, morbidity, disability, and the neurological as well as cognitive aftereffects of stroke, as is clear from the experience of higher-income nations. We recommend a collective intervention involving the governments of nations, international organizations, civil society, and the private sector for greater impact and sustainable outcomes reducing the epidemiology and implications of stroke in SSA.

Stroke occurrence by hypertension treatment status in Ghana and Nigeria: A case-control study

BACKGROUND

Hypertension is preeminent among the vascular risk factors for stroke occurrence. The wide gaps in awareness, detection, treatment, and control rates of hypertension are fueling an epidemic of stroke in sub-Saharan Africa.

PURPOSE

To quantify the contribution of untreated, treated but uncontrolled, and controlled hypertension to stroke occurrence in Ghana and Nigeria.

METHODS

The Stroke Investigative Research and Educational Network (SIREN) is a case-control study across 16 study sites in Ghana and Nigeria. Cases were acute stroke (n = 3684) with age- and sex-matched stroke-free controls (n = 3684). We evaluated the associations of untreated hypertension, treated but uncontrolled hypertension, and controlled hypertension at BP of <140/90 mmHg with risk of stroke occurrence. We assessed the adjusted odds ratio and population-attributable risk of hypertension treatment control status associated with stroke occurrence.

RESULTS

The frequencies of no hypertension, untreated hypertension, treated but uncontrolled hypertension and controlled hypertension among stroke cases were 4.0%, 47.7%, 37.1%, and 9.2% vs 40.7%, 34.9%, 15.9%, and 7.7% respectively among stroke-free controls, p < 0.0001. The aOR and PAR (95% CI) for untreated hypertension were 6.58 (5.15-8.41) and 35.4% (33.4-37.4); treated but uncontrolled hypertension was 9.95 (7.60-13.02) and 35.9% (34.2-37.5); and controlled hypertension 5.37 (3.90-7.41) and 8.5% (7.6-9.5) respectively. Untreated hypertension contributed a PAR of 47.5% to the occurrence of intracerebral hemorrhage vs 29.5% for ischemic stroke. The aOR of untreated hypertension for stroke occurrence was 13.31 (7.64-23.19) for <50 years; 7.14 (4.51-11.31) for 50-64 years; and 3.48 (2.28-5.30) for 65 years or more.

CONCLUSION

The contribution of untreated hypertension and treated but uncontrolled hypertension to stroke occurrence among indigenous Africans is substantial. Implementing targeted interventions that address gaps in hypertension prevention and treatment, involving the local population, healthcare providers, and policymakers, can potentially substantially reduce the escalating burden of strokes in Africa.

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.

More severe initial manifestations and worse short-term functional outcome of intracerebral hemorrhage in the plateau than in the plain

Intracerebral hemorrhage (ICH) is one of the most devastating forms of stroke. However, studies on ICH at high altitude are insufficient. We aimed to compare the initial manifestations, imaging features and short-term functional outcomes of ICH at different altitudes, and further explore the effect of altitude on the severity and prognosis of ICH. We retrospectively recruited ICH patients from January 2018 to July 2021 from two centers at different altitudes in China. Information regarding to clinical manifestations, neuroimages, and functional outcomes at discharge were collected and analyzed. Association between altitude and initial severity, neuroimages, and short-term prognosis of ICH were also investigated. A total of 724 patients with 400 lowlanders and 324 highlanders were enrolled. Compared with patients from the plain, those at high altitude were characterized by more severe preliminary manifestations (P < 0.0001), larger hematoma volume (P < 0.001) and poorer short-term functional outcome (P < 0.0001). High altitude was independently associated with dependency at discharge (adjusted P = 0.024), in-hospital mortality (adjusted P = 0.049) and gastrointestinal hemorrhage incidence (adjusted P = 0.017). ICH patients from high altitude suffered from more serious initial manifestations and worse short-term functional outcome than lowlanders. Control of blood pressure, oxygen supplementation and inhibition of inflammation may be critical for ICH at high altitude.

Knowledge and perspectives of community members on risk assessment for stroke prevention using mobile health approaches in Nigeria

OBJECTIVES

To assess the knowledge of community dwelling adults on stroke risk and their willingness to use mobile health (mHealth) technology in assessing their stroke risk.

MATERIALS AND METHODS

A cross-sectional study was conducted among adults (≥18 years old) using survey questionnaires designed by neurologists and health promotion experts and administered by trained study staff. Logistic regression models were used to assess factors associated with receptivity toward knowing individual stroke risk score and willingness to use a mobile application (App) to assess stroke risk.

RESULTS

The survey was administered to 486 participants in Nigeria, with a mean age of 47.4 ± 15.5 years, comprising 53.5% females. Up to 84% of participants wanted to know their risk for developing stroke but only 29.6% of respondents had ever previously had their stroke risk assessed. Factors associated with willingness to know stroke risk were age [aOR (95% CI): 0.97 (0.95 - 0.99)], and Hausa tribe [16.68 (2.16 - 128.92)]. Up to 66% of participants wanted to know their immediate risk of stroke, compared with 6.6% and 2.1% who wanted to know their 5-year or 10-year future stroke risks respectively. Regarding locations, participants preferred stroke risk assessment to be performed at a health facility, at home by health professional, on their own using mHealth (stroke risk calculator application), or at communal gatherings (decreasing order). About 70% specifically wished to learn about their stroke risk via an mHealth application.

CONCLUSIONS

Community dwelling Nigerians wanted to know their immediate risk of stroke using digital platforms, such as a mobile phone stroke risk calculator application. Clinical trials are needed to assess the effectiveness of such a strategy for primary prevention of stroke in sub-Saharan African communities.

Essential nutrients and cerebral small vessel diseases: a two-sample Mendelian randomization study

Background

Previous studies have suggested a potential association between nutrients and cerebral small vessel disease (CSVD), but this association has not been fully addressed.

Object

We intended to clarify the causal associations between four categories of essential nutrients (amino acids, polyunsaturated fatty acids, minerals and vitamins) and two acute manifestations of CSVD (intracerebral hemorrhage and small vessel stroke) using two-sample Mendelian randomization (MR) analysis.

Method

We obtained European-based large-scale genome-wide association studies (GWASs) related to CSVD (6,255 cases and 233,058 controls) and nutrient concentrations. Causality evaluation mainly included the results of the inverse variance-weighted (IVW) method. The simple median method, the weighted median method and the MR-Egger method were adopted for sensitivity analyses.

Results

For ICH or SVS, increased levels of phenylalanine (OR = 1.188, p < 0.001) and dihomo-gamma-linolenic acid (DGLA) (OR = 1.153, p = 0.001) showed risk effects, while docosapentaenoic acid (DPA) (OR = 0.501, p < 0.001), zinc (OR = 0.919, p < 0.001), and arachidonic acid (OR = 0.966, p = 0.007) showed protective effects. For lobar hemorrhage or SVS, AA (OR = 0.978, p < 0.001), zinc (OR = 0.918, p < 0.001), and retinol (OR = 0.753, p < 0.001) showed risk effects; DPA (OR = 0.682, p = 0.022), gamma-linolenic acid (OR = 0.120, p = 0.033) and 25(OH)D (OR = 0.874, p = 0.040) showed protective effects. For nonlobar hemorrhage or SVS, DGLA (OR = 1.088, p < 0.001) and phenylalanine (OR = 1.175, p = 0.001) showed risk effects.

Conclusion

Our study analyzed the effect of nutrients on CSVD risk from a genetic perspective, with implications for CSVD prevention through nutrient supplementation.

Capacity-Building for Stroke Genomic Research Data Collection: The African Neurobiobank Ethical, Legal, and Social Implications Project Experience

Background: The fields of stroke genomics, biobanking, and precision medicine are rapidly expanding in sub-Saharan Africa. However, the ethical, legal, and social implications (ELSI) of emerging neurobiobanking and genomic data resources are unclear in an emerging African scientific landscape with unique cultural, linguistic, and belief systems. Objective: This article documents capacity-building experiences of researchers during the development, pretesting, and validation of data collection instruments of the African Neurobiobank for Precision Stroke Medicine-(ELSI) Project. Methods: The African Neurobiobank for Precision Stroke Medicine-ELSI project is a transnational, multicenter project implemented across seven sites in Ghana and Nigeria. Guided by the Community-Based Participatory Research framework, we conducted three workshops with key stakeholders to review the study protocol, ensure uniformity in implementation; pretest, harmonize, and integrate context-specific feedback to ensure validity and adaptability of data collection instruments. Workshop impact was assessed using an open-ended questionnaire, which included questions on experience with participation in any of the workshops, building capacity in Genetic and Genomic Research (GGR), level of preparedness toward GGR, the genomic mini-dictionary developed by the team, and its impact in enhancing understanding in GGR. Data were analyzed qualitatively using a thematic framework approach. Results: Findings revealed the usefulness of the workshop in improving participants' knowledge and capacity toward GGR implementation. It further identified local, context-specific concerns regarding quality data collection, the need to develop culturally acceptable, genomic/biobanking data collection tools, and a mini-dictionary. Participants-reported perceptions were that the mini-dictionary enhanced understanding, participation, and data collection in GGR. Overall, participants reported increased preparedness and interest in participating in GGR. Conclusion: Capacity-building is a necessary step toward ELSI-related genomic research implementation in African countries where scholarship of ELSI of genomics research is emerging. Our findings may be useful to the design and implementation of ELSI-GGR projects in other African countries.

Age-to-Glasgow Coma Scale score ratio predicts gastrointestinal bleeding in patients with primary intracerebral hemorrhage

Objective

Recent clinical studies have demonstrated that advanced age and low initial Glasgow Coma Scale (GCS) score were independent predictors of gastrointestinal bleeding (GIB) in patients with primary intracerebral hemorrhage (ICH). However, used singly, age and GCS score have their respective shortcomings in predicting the occurrence of GIB. This study aimed to investigate the association between the age-to-initial GCS score ratio (AGR) and the risk of GIB following ICH.

Methods

We conducted a single-center, retrospective observational study of consecutive patients presenting with spontaneous primary ICH at our hospital from January 2017 through January 2021. Patients who fulfilled the inclusion and exclusion criteria were categorized into GIB and non-GIB groups. Univariate and multivariate logistic regression analyses were implemented to identify the independent risk factors for the occurrence of GIB, and a multicollinearity test was performed. Furthermore, one-to-one matching was conducted to balance important patient characteristics by the groups' propensity score matching (PSM) analysis.

Results

A total of 786 consecutive patients fulfilled the inclusion/exclusion criteria for the study, and 64 (8.14%) patients experienced GIB after primary ICH. Univariate analysis revealed that patients with GIB were significantly older [64.0 (55.0-71.75) years vs. 57.0 (51.0-66.0) years, p = 0.001] and had a higher AGR [7.32 (5.24-8.96) vs. 5.40 (4.31-7.11), p < 0.001] and a lower initial GCS score [9.0 (7.0-11.0) vs. 11.0 (8.0-13.0), p < 0.001]. The multicollinearity test revealed that no multicollinearity was observed in the multivariable models. Multivariate analysis showed that the AGR was a significant independent predictor of GIB [odds ratio (OR) 1.155, 95% confidence interval (CI) 1.041-1.281, p = 0.007], as well as prior anticoagulation or antiplatelet therapy (OR 0.388, 95% CI 0.160-0.940, p = 0.036) and MV used >24 h (OR 0.462, 95% CI 0.252-0.848, p = 0.013). Receiver operating curve (ROC) analysis illustrated that the optimal cutoff value for the AGR as a predictor for GIB in patients with primary ICH was 6.759 [the area under the curve (AUC) was 0.713 with a corresponding sensitivity of 60.94% and specificity of 70.5%, 95% CI 0.680-0.745, p < 0.001]. After 1:1 PSM, the matched GIB group had significantly higher AGR levels compared with the matched non-GIB group [7.47(5.38-9.32) vs. 5.24(4.24-6.40), p <0.001]. The ROC analysis indicated an AUC of 0.747 (the sensitivity was 65.62%, and the specificity was 75.0%, 95% CI 0.662-0.819, p < 0.001) for AGR levels as an independent predictor of GIB in patients with ICH. In addition, AGR levels were statistically correlated with unfunctional 90-day outcomes.

Conclusion

A higher AGR was associated with an increased risk of GIB and unfunctional 90-day outcomes in patients with primary ICH.

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.

Long-term determinants of death after stroke in Ghana: Analysis by stroke types & subtypes

BACKGROUND

Determinants of long-term mortality after stroke by mechanistic type and subtype are unknown in sub-Saharan Africa (SSA). Such data are crucial for targeting specific pathophysiologic pathways to improve stroke outcomes in the region.

PURPOSE

To evaluate rates and predictors of mortality up to 8 years after stroke, by type and subtype, in Ghana.

METHODS

We prospectively collected data on stroke patients presenting at a tertiary medical facility in Ghana between 2013 and 2018 who were followed up until October 31, 2021. Stroke diagnosis was confirmed using a Computerized Tomography scan; ischemic strokes were mechanistically typed using the TOAST classification while intracerebral hemorrhages were subtyped using the SMASH-U scheme. Demographic and clinical predictors of stroke mortality were evaluated using Cox proportional hazards regression modelling.

RESULTS

Of 564 patients encountered during the study period, data on vital status were available for 556 (98.6%) subjects at discharge and 442 (78.4%) on follow-up. Mean age was 61.1 ±15.1 years, and 223 (53.1%) were male. Mortality rates at 1, 3, 12, 36, 60 and 96 months were 37.5%, 43.2%, 49.7%, 57.4%, 62.9%, and 73.7% respectively. Three (3) factors remained significantly associated with risk of death namely age, adjusted hazard ratios (aHR) of 1.12 (95%CI: 1.04-1.20), no formal education 1.36 (95% CI: 1.02-1.81) and modified Rankin score 1.67 (95%CI: 1.42 - 1.98) for each unit rise. For ischemic stroke the four (4) factors associated with long-term mortality were low formal education, low monthly income, having diabetes mellitus and higher functional score on admission. For intracerebral hemorrhage, the two factors were increasing age and high functional score.

CONCLUSION

Stroke severity is the key predictor of long-term mortality after an index stroke in Ghana, regardless of the underlying pathophysiologic mechanism. Instituting acute stroke systems of care to facilitate timely reperfusion efforts may greatly improve long term survival outcomes after stroke in SSA.

Review of Long-Term Blood Pressure Control After Intracerebral Hemorrhage: Challenges and Opportunities

Blood pressure (BP) is the most important modifiable risk factor for intracerebral hemorrhage (ICH). Elevated BP is associated with an increased risk of ICH, worse outcome after ICH, and in survivors, higher risks of recurrent ICH, ischemic stroke, myocardial infarction, and cognitive impairment/dementia. As intensive BP control probably improves the chances of recovery from acute ICH, the early use of intravenous or oral medications to achieve a systolic BP goal of <140 mm Hg within the first few hours of presentation is reasonable for being applied in most patients. In the long-term, oral antihypertensive drugs should be titrated as soon as possible to achieve a goal BP <130/80 mm Hg and again in all ICH patients regardless of age, location, or presumed mechanism of ICH. The degree of sustained BP reduction, rather than the choice of BP-lowering agent(s), is the most important factor for optimizing risk reduction, with varying combinations of thiazide-type diuretics, long-acting calcium channel blockers, ACE (angiotensin-converting enzyme) inhibitors or angiotensin receptor blockers, being the mainstay of therapy. As most patients will require multiple BP-lowering agents, and physician inertia and poor adherence are major barriers to effective BP control, single-pill combination therapy should be considered as the choice of management where available. Increased population and clinician awareness, and innovations to solving patient, provider, and social factors, have much to offer for improving BP control after ICH and more broadly across high-risk groups. It is critical that all physicians, especially those managing ICH patients, emphasize the importance of BP control in their practice.

Utilizing Implementation Science to Bridge Cerebrovascular Health Disparities: a Local to Global Perspective

PURPOSE OF REVIEW

Stroke is a prime example of a medical disorder whose incidence, prevalence, and outcomes are strongly characterized by health disparities across the globe. This scoping literature review seeks to depict how implementation science could be utilized to advance health equity in the prevention, acute treatment, and post-acute management of stroke in the underserved regions of high-income countries as well as in all low-income countries.

RECENT FINDINGS

A major reason for the persisting and widening cerebrovascular disease disparities is that evidence-based stroke prevention and treatment interventions have been differentially translated (if at all) to various populations and settings. The field of implementation science is endowed with frameworks, theories, methodological approaches, and outcome measures, including equity indices, which could be harnessed to facilitate the translation of evidence-based interventions into clinical practice for underserved and vulnerable communities. Encouragingly, there are several novel frameworks, which eminently merge implementation science constructs with health equity determinants, thereby opening up key opportunities to bridge burgeoning worldwide gaps in cerebrovascular health equity.

Apparent Treatment-Resistant Hypertension Among Stroke Survivors: A Transcontinental Study Assessing Impact of Race and Geography

BACKGROUND

Race and geographic differences in the prevalence and predictors of hypertension in stroke survivors have been reported, but apparent treatment-resistant hypertension (aTRH) among stroke survivors by race (African ancestry vs. non-Hispanic Caucasians) and by geography (continental Africa vs. the United States) are under studied.

METHODS

This is a cross-sectional study using ethically approved stroke registries from the University of Florida and the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. Univariate and multivariate regression was used to evaluate for differences in prevalence of aTRH and associations with clinical covariates.

RESULTS

Harmonized data were available for 3,365 stroke survivors of which 943 (28.0%) were indigenous Africans, 558 (16.6%) African Americans, and 1,864 (55.4%) non-Hispanic Caucasians with median ages (interquartile range) of 59 (49-68), 61 (55-72), and 70 (62-78) years, P < 0.0001. The overall frequency of aTRH was 18.5% (95% confidence interval [CI]: 17.2%-19.8%) with 42.7% (95% CI: 39.6%-46.0%) among indigenous Africans, 16.1% (95% CI: 13.2%-19.5%) among African Americans, and 6.9% (95% CI: 5.8%-8.2%) among non-Hispanic Caucasians, P < 0.0001. Five factors associated with aTRH: age, adjusted odds ratio (95% CI) of 0.99 (0.98-0.99), female sex 0.70 (0.56-0.87), cigarette smoking 1.98 (1.36-2.90), intracerebral hemorrhage 1.98 (1.57-2.48), and Black race namely indigenous Africans 4.42 (3.41-5.73) and African Americans 2.44 (1.81-3.29).

CONCLUSIONS

Future studies are needed to investigate the contribution of socioeconomic disparities in the prevalence aTRH in those with African Ancestry to explore the long-term impact, and evaluate effective therapeutic interventions in this subpopulation.

The 2021 William Feinberg Award Lecture Seeking Glocal Solutions to Cerebrovascular Health Inequities

Global and local (“glocal”) disparities in stroke incidence, prevalence, care, and mortality are persistent, pervasive, and progressive. In particular, the disproportionate burden of stroke in people of African ancestry compared to most other racial/ethnic groups around the world has been long standing, is expected to worsen, and so far, has defied solution, largely because conventional risk factors likely account for less than half of the Black versus White disparity in stroke outcomes. While hypotheses such as a differential impact or inadequate evaluation of traditional risk factors by race have been suggested as potentially key factors contributing to lingering racial/ethnic stroke disparities, relatively understudied novel risk factors such as psychosocial stress, environmental pollution, and inflammation; and influences of the social determinants of health are gaining the most attention (and momentum). Moreover, it is increasingly recognized that while there is a lot still to understand, there needs to be a major shift from incessantly studying the problem, to developing interventions to resolve it. Resolution will likely require targeting multilevel factors, considering contemporaneous cross-national and cross-continental data collection, creating scalable care delivery models, jointly addressing care quality and community drivers of stroke occurrence, incorporating policy makers in planning/dissemination of successful interventions, and investing in robust transdisciplinary research training programs that address the interrelated issues of health equity and workforce diversity, and regional capacity building. To this end, our international multidisciplinary team has been involved in conducting several epidemiological studies and clinical trials in the area of stroke disparities, as well as executing career enhancing research training programs in the United States and Africa. This award lecture paper shares some of the lessons we have learnt from previous studies, presents objectives/design of ongoing initiatives, and discusses plans for the future.

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.

Frequency and factors associated with post-stroke seizures in a large multicenter study in West Africa

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 3344 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 < 50 years, aOR of 1.59 (1.08-2.33), National Institute of Health Stroke Score (NIHSS), 1.29 (1.16-1.42) for each 5 units rise and white cell count 1.07 (1.01-1.13) for each 10^3 mm3 rise. Factors associated with PSS in ischemic were NIHSS score, aOR of 1.17 (1.04-1.31) and infarct volume of 10-30 cm3 aOR of 2.17(1.37-3.45). Among ICH, associated factors were alcohol use 5.91 (2.11-16.55) and lobar bleeds 2.22 (1.03-4.82).

CONCLUSION

The burden of PSS among this sample of west Africans is substantial and may contribute to poor outcomes of stroke in this region. Further longitudinal studies are required to understand the impact on morbidity and mortality arising from PSS in Africa.

Quantitative and qualitative analyses of herbal medication use among Ghanaian stroke survivors

BACKGROUND

Herbal medicines are not regulated by regulatory authorities and are often not of proven safety and efficacy. Anecdotal reports suggest widespread use of traditional herbal medicine (THM) for treatment of stroke in Africa, but verifiable data are limited in published literature.

OBJECTIVE

To assess the frequency and reasons for THM use among Ghanaian stroke survivors.

METHODS

We conducted a cross-sectional survey of 106 consecutive stroke survivors presenting for care at a tertiary medical center in Kumasi, Ghana between June and October 2020. Information on demographic, clinical, vascular risk factors and use of THM were collected in a non-judgmental manner and analyzed.

RESULTS

Among the cohort, 46 (43.4%) reported use of any THM for their stroke management. There was a trend towards fewer women who reported use of THM 34.8% vs 53.3%, p = 0.06. Of those reporting use of THM, 78% had blood pressure > 140/90 mmHg vs. 56% among those not exposed to THM (p = 0.02). Top reasons proffered for use of THM were: expecting them to aid faster recovery from stroke (n = 30), expecting them to cure stroke (n = 18), and expecting them to be of superior effectiveness compared to approved conventional medications of proven efficacy/safety (n = 1).

CONCLUSION

Almost half the individuals in this contemporary sample of Ghanaian stroke survivors reported use of THM with expectations for improved outcomes. More counseling is required to inform patients about potential safety issues with THM use, and more research is needed to explore risk/benefit of promising THMs to improve stroke outcomes.

Risk factors and outcomes of hospitalized stroke patients in Lusaka, Zambia

BACKGROUND

Limited data exists about stroke risk factors and outcomes in sub-Saharan African countries, including Zambia. We aim to fill this gap by describing features of hospitalized stroke patients at University Teaching Hospital (UTH), the national referral hospital in Lusaka, Zambia.

METHODS

We conducted a retrospective study of consecutive adults with stroke admitted to UTH's inpatient neurology service from October 2018 to March 2019. Strokes were classified as ischemic or hemorrhagic based on CT scan results and unknown if CT scan was not obtained. Chi-square analyses and t-tests were used to compare characteristics between cohorts with differing stroke subtypes.

RESULTS

Adults with stroke constituted 43% (n = 324) of all neurological admissions, had an average age of 60 ± 18 years, and 62% of the cohort was female. Stroke subtypes were 58% ischemic, 28% hemorrhagic, and 14% unknown. Hypertension was present in 80% of all strokes and was significantly associated with hemorrhagic stroke (p = 0.03). HIV was present in 18% of all strokes and did not significantly differ by stroke subtype. Diabetes (16%), heart disease (34%), atrial fibrillation (9%), and past medical history of stroke (22%) were all significantly more common in patients with ischemic stroke (p < 0.05). In-hospital mortality was 24% overall and highest among individuals with hemorrhagic strokes (33%, p = 0.005).

CONCLUSIONS

This Zambian stroke cohort is notable for its young age, significant HIV burden, high in-hospital mortality, and high rates of uncontrolled hypertension. Our results demonstrate Zambia's substantial stroke burden, significant contribution of HIV to stroke, and the need to improve primary stroke prevention.

Atherosclerotic event risk and risk reduction therapies among Ghanaian hemorrhagic stroke survivors

BACKGROUND

Intracerebral hemorrhage (ICH) stroke constitute up to 40% of incident strokes in Africa. While ICH patients are at high risk for atherosclerotic events, the risk-benefit of anti-atherosclerotic therapies in this patient population is uncertain.

PURPOSE

To assess whether utility of statins and/or antithrombotic agents after surviving an ICH correlates with atherosclerotic risk of an observational cohort.

METHODS

We analyzed data in a stroke registry prospectively collected on consecutively encountered stroke survivors seen at an out-patient clinic in Ghana between January 2018 and March 2020. We collected baseline demographic and clinical details, including diagnosis of ICH, co-morbidities, and key atherosclerotic risk reduction therapies (statins and anti-platelet drugs). We computed ischemic vascular risk using the Framingham Risk Score (FRS) to classify patients into low, intermediate and high vascular risk.

RESULTS

Of 1101 stroke survivors seen during the period, 244 (22.2%) had ICH. Vascular risk profiles were low (n = 86; 35.2%), intermediate (n = 71; 29.1%) and high (n = 87; 35.7%). Utility of statin use was 76.7% (low risk), 84.5% (intermediate risk), and 87.4% (high risk), p = 0.16 while antiplatelet use trended with atherosclerotic risk being 9.3% (low risk), 25.4% (intermediate risk), and high risk (34.5%), p = 0.0004. Independent factors associated with statin use were hypertension (OR 8.80; 95% CI: 2.34-33.11) and cigarette smoking (OR 0.29; 95% CI: 0.09-0.89) while antiplatelet drug use was associated with age (OR 1.43; 95% CI: 1.06-1.92) and time from index stroke (OR: 1.02; 95% CI: 1.01-1.02).

CONCLUSION

Approximately two-thirds of ICH survivors in this African sample had intermediate to high risk of future atherosclerotic events. Clinical trials on the timing, safety, and efficacy of statins and antiplatelet drugs among ICH survivors could help better guide risk mitigation in this population.

Stroke in Africa: profile, progress, prospects and priorities

Stroke is a leading cause of disability, dementia and death worldwide. Approximately 70% of deaths from stroke and 87% of stroke-related disability occur in low-income and middle-income countries. At the turn of the century, the most common diseases in Africa were communicable diseases, whereas non-communicable diseases, including stroke, were considered rare, particularly in sub-Saharan Africa. However, evidence indicates that, today, Africa could have up to 2-3-fold greater rates of stroke incidence and higher stroke prevalence than western Europe and the USA. In Africa, data published within the past decade show that stroke has an annual incidence rate of up to 316 per 100,000, a prevalence of up to 1,460 per 100,000 and a 3-year fatality rate greater than 80%. Moreover, many Africans have a stroke within the fourth to sixth decades of life, with serious implications for the individual, their family and society. This age profile is particularly important as strokes in younger people tend to result in a greater loss of self-worth and socioeconomic productivity than in older individuals. Emerging insights from research into stroke epidemiology, genetics, prevention, care and outcomes offer great prospects for tackling the growing burden of stroke on the continent. In this article, we review the unique profile of stroke in Africa and summarize current knowledge on stroke epidemiology, genetics, prevention, acute care, rehabilitation, outcomes, cost of care and awareness. We also discuss knowledge gaps, emerging priorities and future directions of stroke medicine for the more than 1 billion people who live in Africa.

Insights in the pathophysiology of haemorrhagic strokes in a sub-Sahara African country, an epidemiological and MRI study

OBJECTIVE

Intra-cerebral Haemorrhage (ICH) seems more prevalent in sub-Saharan Africa (SSA) than in High-Income Countries (HIC) with poorer clinical outcome. Higher impact of hypertension and/or amyloid angiopathy could account for this disproportion. Here, we sought to (i) retrospectively compare ICH clinical and imaging patterns in Belgium and Guinea and in a subsequent cohort (ii) prospectively compare brain MRI characteristics to seek evidence for a different proportion of amyloid angiopathy patterns.

METHODS

Ninety one consecutive patients admitted for spontaneous ICH at Brussels Erasme-ULB Hospital and at Conakry Ignace Deen-UGANC were retrospectively compared in terms of ICH volume estimated with the ABC/2 method, clinical characteristics and modified ranking (mRS) score at 30 days. mRS was dichotomised as good outcomes (≤3) and poor outcomes (>3). A prospective cohort of 30 consecutive patients with ICH admitted at CHU Conakry Ignace Deen-UGANC was prospectively included to undergo brain MRI. Results of the Guinean MRI were compared to 30 patients randomly selected from Brussels' initial cohort. Paired Student's t-test and Mann-Whitney u-test were used for group comparisons.

RESULTS

Age of ICH onset was higher in Belgium (68 ± 17 years vs. 56 ± 14 years, P < 0.01) while ICH volume and 30-day mortality rate were higher in Guinea (20 ml vs. 11 ml, P < 0.01 and mortality 33% vs. 10 %, P < 0.01). ICH burden in survivors in Conakry and Brussels showed respectively good outcomes in 56.7% and 60.4% (P = 0.09) and poor outcomes in 10.3% vs. 29.6% (P < 0.001). MRI analysis of the prospective cohort failed to disclose significant differences regarding brain MRI characteristics.

CONCLUSIONS

Intra-cerebral Haemorrhage affected patients 15 years younger in Guinea with larger haematoma volumes and higher mortality than in Belgium. MRI findings did not show more prevalent amyloid angiopathy pathology suggesting that better primary prevention of hypertension could positively impact ICH epidemiology in Guinea.

Antecedent febrile illness and occurrence of stroke in West Africa: The SIREN study

BACKGROUND

Acute infections have been posited as potential precipitants or triggers of the occurrence of stroke among adults with traditional vascular risk factors. We evaluated associations between stroke occurrence and reported febrile illness within 4 weeks (potential antecedent infections) 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 radiologically confirmed strokes. Controls were stroke-free adults matched with cased by age, gender and ethnicity. Detailed evaluations for vascular, lifestyle and psychosocial factors were performed. Participants were asked for evidence of any febrile illness within the past 4 weeks. We used conditional logistic regression to estimate adjusted odds ratios (aOR) with 95% Confidence Interval.

RESULTS

Among 3588 stroke cases recruited in Ghana and Nigeria between August 2014 and July 2018, 363 cases (10.1%) reported having a febrile illness within the 4 weeks prior to stroke occurrence. Having an antecedent infection was associated with stroke occurrence with an unadjusted OR of 1.19 (1.00-1.51) but aOR of 0.83 (0.59-1.17) upon adjusting for traditional vascular risk factors. Stress, aOR of 4.69 (2.59-8.50) and consumption of green vegetables 2.27 (1.35-2.85) were associated with antecedent febrile illness.

CONCLUSION

1 in 10 stroke cases reported antecedent history of febrile illness prior to occurrence of stroke but no independent association was observed in this study. Infectious exposures may be important triggers of cardiovascular events requiring further exploratory studies to better understand the role of this emerging risk factor.

Prevalence and predictors of post-stroke epilepsy among Ghanaian stroke survivors

BACKGROUND

Post-stroke epilepsy (PSE) is associated with poorer quality of life, higher mortality, and greater health expenditures. We are unaware of any published reports on the frequency of and factors associated with PSE in Africa.

PURPOSE

To assess the frequency and factors associated with PSE among Ghanaian stroke survivors.

METHODS

We conducted a cross-sectional study of consecutive stroke survivors seen at an out-patient Neurology clinic enrolled into a stroke registry at a tertiary medical center in Ghana between January 2018 and March 2020. We collected baseline demographic and clinical details including diagnosis of post-stroke epilepsy, anti-epileptic medications, presence, treatment and control of vascular risk factors. Multivariate logistic regression models were constructed to identify factors associated with PSE.

RESULTS

Of 1101 stroke patients encountered, 126 had PSE (frequency of 11.4%; 95% CI of 9.6-13.5%). Mean (± SD) age among PSE vs. non-PSE patients was 57.7 (± 15.2) vs. 58.7 (± 13.9) years. Factors independently associated with PSE were being male (aOR 1.94; 95% CI: 1.32-2.86), cortical ischemic strokes (1.79; 1.12-2.87), blood pressure > 130/80 mmHg (OR 2.26; 1.06-4.79), use of antihypertensive treatment (OR 0.43; 0.23-0.79). There was an inverted J-shaped curve association between number of classes of antihypertensive drugs prescribed and occurrence of PSE, with the lowest inflection point at 3 classes (OR 0.34; 0.17-0.68).

CONCLUSION

In this convenience sample of ambulatory Ghanaian stroke survivors, one in ten had PSE. Further investigations to confirm and clarify the associations between the identified demographic and clinical characteristics are warranted.

Frequency and factors linked to refractory hypertension among stroke survivors in Ghana

BACKGROUND

Refractory hypertension (RfH) is a rare, severe phenotype of resistant hypertension, linked to higher risk of adverse cardiovascular outcomes. Little is known about the association of RfH with stroke type and subtype.

OBJECTIVE

To determine the prevalence and predictors of RfH among stroke survivors in Ghana.

METHODS

We interrogated the dataset of a prospectively collected registry of hypertensive patients seen between July 2015 and June 2019, at five hospitals in Ghana. We compared stroke survivors to stroke-free controls. Clinic-based blood pressure was measured using a standardized protocol and antihypertensive medications were assessed via review of medical records and inspection of pills. Refractory hypertension was defined as office BP ≥140/90 mmHg on ≥5 classes of antihypertensive medications. Multivariate logistic regression models were constructed to assess factors associated with RfH.

RESULTS

Of 3927 hypertensive patients (1169 stroke survivors, 2758 controls), 86 had RfH for an overall prevalence of 2.2% (95% CI: 1.8-2.7%). Among patients with RfH, 5.8% (4.5-7.3%) were stroke survivors vs. 0.7% (0.4-1.0%) were stroke-free (p < .0001). Adjusted odds ratio (95% CI) for factors associated with RfH were being male (1.81, 1.15-2.85), age < 60 years (2.64, 1.59-4.40), chronic kidney disease (2.09, 1.21-3.60), and known stroke (7.53, 4.35-13.04). RfH was associated with intracerebral hemorrhage, (11.43, 5.65-23.14), ischemic stroke (9.76, 5.47-17.42), lacunar stroke (13.58, 6.45-28.61), and non-lacunar ischemic stroke (3.67, 1.04-13.02).

CONCLUSION

Presence of RfH is significantly accentuated among stroke survivors. Intensified efforts are warranted to identify and aggressively address barriers to control in these patients to avert subsequent vascular events.

Prevalence and predictors of statin utilization among patient populations at high vascular risk in Ghana

BACKGROUND

Inadequate implementation of evidence-based preventive measures for individuals at high risk of cardiovascular disease (CVD) will only worsen the current epidemic of CVDs in sub-Saharan Africa. We assessed rates and predictors of statin utilization among two high CVD risk patient populations, people with type 2 diabetes mellitus (T2DM) and those with stroke, encountered across five hospitals in Ghana.

METHODS

A cross-sectional study among 1427 patients with T2DM and 159 stroke survivors encountered at 5 hospitals (1 primary-level, 2 secondary level and 2 tertiary level) in Ghana between July 2015 and June 2018. We collected baseline demographic and clinical details including statin prescription from medical records. Factors associated with statin prescription among T2DM for primary prevention and stroke survivors for secondary prevention were evaluated using multivariate logistic regression analysis.

RESULTS

Among patients with T2DM without CVDs, 240 (16.8%) were on statins for primary prevention. Factors associated with statin use among diabetics expressed as aOR (95% CI) were being treated at a tertiary level hospital 5.86 (3.22-10.68), hypertension comorbidity 1.80 (1.25-2.60), and lower income 0.43 (0.26-0.70). Among 159 stroke survivors, 22 (14.0%) were on statins with the following associated factors: lower income 0.16 (0.03-0.77), secondary level vs. tertiary level education 0.21 (0.05-0.97) and having T2DM 4.69 (1.63-13.49).

CONCLUSION

Approximately 1 in 6 individuals with T2DM without CVD and 1 in 7 stroke survivors are prescribed statins in Ghana. Efforts to bridge this practice gap and improve access to life saving preventative medications for CVD risk reduction in low-and-middle income countries are urgently warranted.