Brain computed tomography perfusion analysis in HIV-seropositive adults with and without neurocognitive impairment in Nigeria: outcomes and challenges of a pilot study.

Introduction: the significance of cerebrovascular disease in HIV-associated neurocognitive disorder (HAND) in a homogeneous black population has not yet been determined. This incident case-control study used CT perfusion imaging to quantify and compare regional cerebral blood flow parameters in neuro-cognitively impaired and unimpaired HIV+ participants of the Ibadan Cohort on Neuro AIDS (ICON) in Nigeria. Methods: this was an incident case-control study consisting of twenty-seven HIV+ adults, classified based on Frascati criteria into neurocognitive impaired (n=18) and unimpaired (n=9) groups, who had brain computed tomographic perfusion (CTP) with a 64-slice Toshiba T scanner. The standard deviation (SD) of regional mean transit time (MTT), cerebral blood flow (CBF), and cerebral blood volume (CBV) values were calculated for bilateral basal ganglia (BG), frontal, parietal, temporal, and occipital regions from CT perfusion maps. The regional mean values and variability (SD) in the CTP measures were compared in the groups using an independent student t-test. Results: differentially higher variability in the bilateral CBF measures in the parietal (right; OR = 1.14, x̄ =5.61, p=0.041, CI=0.27-11.35/left; OR = 1.16, x̄=7.01, p=0.03, CI=5.6-13.47) and time to peak (TTP) measures in the basal ganglia (right; OR = 3.78, x̄=0.88, p=0.032, CI=0.081-1.67/left; OR = 2.44, x̄=1.48, p=0.020, CI=0.26-2.71) and occipital (right; OR = 2.18, x̄=1.32, p=0.018, CI=0.25-2.38/left; OR = 1.93, x̄=1.08, p=0.034, CI=0.086-2.06) regions were observed in the cognitively impaired group compared to the unimpaired group. Conclusion: the study evidence suggests that alterations in cerebral perfusion implicated in HIV-associated neurocognitive disorder may be possibly demonstrated using CTP, a readily available resource in most African countries saddled with the highest burden of HIV.

Frequency & factors associated with recurrent stroke in Ghana and Nigeria.

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

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.

Echocardiographic Abnormalities and Determinants of 1-Month Outcome of Stroke Among West Africans in the SIREN Study.

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.

Knowledge, attitudes and practices of West Africans on genetic studies of stroke: Evidence from the SIREN Study.

BACKGROUND: It is crucial to assess genomic literacy related to stroke among Africans in preparation for the ethical, legal and societal implications of the genetic revolution which has begun in Africa. OBJECTIVE: To assess the knowledge, attitudes and practices (KAP) of West Africans about stroke genetic studies. METHODS: A comparative cross-sectional study was conducted among stroke patients and stroke-free controls recruited across 15 sites in Ghana and Nigeria. Participants' knowledge of heritability of stroke, willingness to undergo genetic testing and perception of the potential benefits of stroke genetic research were assessed using interviewer-administered questionnaire. Descriptive, frequency distribution and multiple regression analyses were performed. RESULTS: Only 49% of 2029 stroke patients and 57% of 2603 stroke-free individuals knew that stroke was a heritable disorder. Among those who knew, 90% were willing to undergo genetic testing. Knowledge of stroke heritability was associated with having at least post-secondary education (OR 1.51, 1.25-1.81) and a family history of stroke (OR 1.20, 1.03-1.39) while Islamic religion (OR=0.82, CI: 0.72-0.94), being currently unmarried (OR = 0.81, CI: 0.70-0.92), and alcohol use (OR = 0.78, CI: 0.67-0.91) were associated with lower odds of awareness of stroke as a heritable disorder. Willingness to undergo genetic testing for stroke was associated with having a family history of stroke (OR 1.34, 1.03-1.74) but inversely associated with a medical history of high blood pressure (OR = 0.79, 0.65-0.96). CONCLUSION: To further improve knowledge of stroke heritability and willingness to embrace genetic testing for stroke, individuals with less formal education, history of high blood pressure and no family history of stroke require targeted interventions.

Self-reported sulphonamide hypersensitivity reactions in adults living in Ibadan, Nigeria: A cross-sectional, community-based study.

BACKGROUND: Documentation of adverse drug reactions (ADRs) is critical to a safe health delivery system. The aim of our study was to explore the prevalence of self-reported sulphonamide hypersensitivity reactions in a community-based sample of the general population in Ibadan, Nigeria. We also examined sociodemographic factors associated with ADRs in the sample. PATIENTS AND METHODS: The study was cross-sectional in design with study sites in urban, semiurban, and rural settlement areas. Pretested questionnaires were administered on a one-on-one basis by trained interviewers. Frequency tables and percentages were computed for various levels of the variables. Chi-square test was used to assess the relationship between sulphonamide hypersensitivity and variables such as sociodemographic characteristics of respondents, respondents' knowledge of drugs, as well as drug sources. Variables found to be significantly associated with sulphonamide hypersensitivity were further investigated using multiple logistic regressions analysis. RESULTS: Out of the 1062 respondents, 15.5% reported hypersensitivity to sulphonamides with skin reactions being the most prevalent. The proportion reporting ADRs was significantly higher among respondents with tertiary education (23.1%) than any other level of education (P = 0.008). In addition, individuals who were very knowledgeable about drug use (odds ratio[OR]: 2.07; 95% confidence interval [CI]: 1.15-3.73) and persons who got drugs from hospitals (OR: 2.00; 95% CI: 1.10-3.65) were more likely to report ADRs than those who were ignorant about drugs and those who purchased drugs from open markets, respectively. CONCLUSION: Prevalence of sulphonamide hypersensitivity is high among respondents, and ADRs is likely to be reported by people who are knowledgeable about drug use.