Screening for Atrial Fibrillation in Sub-Saharan Africa: A Health Economic Evaluation to Assess the Feasibility in Nigeria.

Background: Cardiovascular disease reflects a major burden of non-communicable disease in Sub-Saharan Africa (SSA). Early detection and treatment of atrial fibrillation (AF), as a preventive measure against stroke, is currently not in the scope of the World Health Organization recommendation to reduce cardiovascular disease. Objective: We hypothesized that screening for AF would be an important approach to determine the true AF prevalence in the general population in African countries and to identify asymptomatic AF patients at risk for stroke to optimize prevention. Methods: A decision analytic model was developed to study the health-economic impact of AF screening in Nigeria over a life-time horizon. The patient population explored in the model was a population of newly detected AF cases that would be diagnosed with a one-time systematic screening for AF with a single lead ECG device in community health centres across Nigeria. Conclusions: The health gain per newly detected AF patient (N = 31,687) was 0.41 QALY at a cost of $5,205 per patient with 100% NOAC use, leading to an ICER of $12,587 per QALY gained. The intervention was cost-effective with a 99.9% warfarin use with an ICER of $1,363 per QALY gained. The total cost of a single screening session was $7.3 million for the total screened population in Nigeria or $1.60 per patient screened. Screening for AF to detect AF patients in need for stroke prevention can be a cost-effective intervention in the Sub-Saharan region, depending on type of anticoagulant used and drug costs.

Genetic Epidemiology and Associated Diseases of APOL1: A Narrative Review.

BACKGROUND: The Apolipoprotein 1 (APOL1) protein is a product of the human APOL1 gene located on chromosome 22q13.1 and performs functions including lipid transport and metabolism, programmed cell death, autophagy and innate immunity against intracellular pathogens. It is unique among its gene family in its possession of a signal peptide that confers on it the ability for export out of the cell and into the blood stream. The aim of this review is to explore the genetic epidemiology and biology of the APOL1 gene, describe its association with different renal and extra-renal disorders and highlight the timelines of the discoveries of the various associations. METHODS: A literature search was carried out using combination of terms including "apolipoproteins", "apolipoprotein L", "APOL1", "genetics of APOL1", "Chronic Kidney Disease (CKD) and APOL1"," APOL1 and associated diseases" covering the period January 1990 to April 2020. RESULTS: High frequency of the APOL1 gene arose as a result of natural selection in East and West Africa, regions endemic for Trypanosoma brucei infection. High frequencies are also reported among individuals of African ancestry in North America. APOL1 G1 and G2 variants protect against Trypanosoma brucei rhodesiense having overcome their virulence through the serum trypanolytic factor. Although protective against infection from trypanosomes, these alleles have also been shown to increase the risk of several disorders including various forms of chronic kidney diseases, schizophrenia, stroke, cancer, and pre - eclampsia. CONCLUSION: The elucidation of the APOL1 gene has deepened understanding of racial disparities in health and disease. Growing understanding of the genetics and functions of APOL1 has potential to enhance translational benefits for development of new biomarkers, preventive and therapeutic interventions in the context of precision medicine.

RÉSUMÉ: La protéine Apolipoprotéine 1 (APOL1) est un produit du gène humain APOL1 situé sur le chromosome 22q13.1 et remplit des fonctions telles que le transport et le métabolisme des lipides, la mort cellulaire programmée, l'autophagie et l'immunité innée contre les agents pathogènes intracellulaires. Il est unique parmi sa famille de gènes en ce qu'il possède un peptide signal qui lui confère la capacité de s'exporter hors de la cellule et dans la circulation sanguine. L'objectif de cette revue est d'explorer l'épidémiologie génétique et la biologie du gène APOL1, de décrire son association avec différentes maladies rénales et extra-rénales et de mettre en évidence la chronologie des découvertes des différentes associations. MÉTHODES: Une recherche bibliographique a été effectuée en utilisant une combinaison de termes comprenant « apolipoprotéines ¼, « apolipoprotéine L ¼, « APOL1 ¼, « génétique d'APOL1 ¼, « Maladie rénale chronique (CKD) et APOL1 ¼, « APOL1 et maladies associées ¼ période de janvier 1990 à avril 2020. RÉSULTATS: La fréquence élevée du gène APOL1 est apparue à la suite de la sélection naturelle en Afrique de l'Est et de l'Ouest, régions endémiques pour l'infection à Trypanosoma brucei. Des fréquences élevées sont également signalées chez les individus d'ascendance africaine en Amérique du Nord. Les variants APOL1 G1 et G2 protègent contre Trypanosoma brucei rhodesiense après avoir surmonté leur virulence grâce au facteur trypanolytique sérique. Bien qu'ils protègent contre l'infection par les trypanosomes, il a également été démontré que ces allèles augmentent le risque de plusieurs troubles, notamment diverses formes de maladies rénales chroniques, la schizophrénie, les accidents vasculaires cérébraux, le cancer et la pré-éclampsie. CONCLUSION: L'élucidation du gène APOL1 a approfondi la compréhension des disparités raciales en matière de santé et de maladie. La compréhension croissante de la génétique et des fonctions d'APOL1 a le potentiel d'améliorer les avantages translationnels pour le développement de nouveaux biomarqueurs, d'interventions préventives et thérapeutiques dans le contexte de la médecine de précision. MOTS-CLÉS: APOL1 ; La génétique; Épidémiologie; La biologie; Maladies associées.

Changes in mediators of inflammation and pro-thrombosis after 12 months of dietary modification in adults with metabolic syndrome.

OBJECTIVE: This study evaluated the effects of a 12-month dietary modification on indices of inflammation and pro-thrombosis in adults with metabolic syndrome (MS). MATERIALS AND METHODS: This longitudinal study involved 252 adults with MS recruited from the Bodija market, Ibadan and its environs. Participants were placed on 20%, 30% and 50% calories obtained from protein, total fat and carbohydrate respectively and were followed up monthly for 12 months. Anthropometry and blood pressure were measured using standard methods. Fasting plasma glucose (FPG), total cholesterol (TC), triglycerides (TG), high density lipoprotein-cholesterol (HDL-C), fibrinogen, plasminogen activator inhibitor-1 (PAI-1)], interleukin-6 (IL-6) and interleukin-10 (IL-10) were measured using spectrophotometric methods and ELISA as appropriate. Data was analysed using ANCOVA, Student's t-test, Mann-Whitney U and Wilcoxon signed-rank tests. P-values less than 0.05 were considered significant. RESULTS: After 6 months of dietary modification, there was a significant reduction in waist circumference (WC), while the levels of HDL-C, fibrinogen and PAI-1 were significantly increased when compared with the corresponding baseline values. However, WC and fibrinogen reduced significantly, while HDL-C and IL-10 significantly increased after 12 months of dietary modification as compared with the respective baseline values. CONCLUSION: Long-term regular dietary modification may be beneficial in ameliorating inflammation and pro-thrombosis in metabolic syndrome.

Can common carotid intima media thickness serve as an indicator of both cardiovascular phenotype and risk among black Africans?

BACKGROUND: It is not known whether common carotid intima media thickness (CIMT) can serve as a surrogate marker of cardiovascular risk among black Africans. Therefore, we examined whether CIMT differed significantly among individuals with distinct cardiovascular phenotype and correlated significantly with traditional cardiovascular risk factors in a black African population. METHODS: CIMT was measured in 456 subjects with three distinct cardiovascular phenotypes - 175 consecutive Nigerian African stroke patients, 161 hypertensive patients without stroke and 120 normotensive non-smoking adults. For each pair of cardiovascular phenotypes, c-statistics were obtained for CIMT and traditional vascular risk factors (including age, gender, weight, waist circumference, smoking, alcohol, systolic and diastolic blood pressures, fasting plasma glucose, fasting total cholesterol). Pearson's correlation coefficients were calculated to quantify bivariate relationships. FINDINGS: Bilaterally, CIMT was significantly different among the three cardiovascular phenotypes (right: p < 0.001, F = 33.8; left: p < 0.001, F = 48.6). CIMT had a higher c-statistic for differentiating stroke versus normotension (c = 0.78 right; 0.82 left, p < 0.001) and hypertension versus normotension (c = 0.65 right; 0.71 left, p < 0.001) than several traditional vascular risk factors. Bilaterally, combining all subjects, CIMT was the only factor that correlated significantly (right: 0.12 ≤ r ≤ 0.41, 0.018 ≤ p < 0.0001; left: 0.18 ≤ r ≤ 0.41, 0.005 ≤ p < 0.0001) to all the traditional cardiovascular risk factors assessed. CONCLUSION: Our findings support CIMT as a significant indicator of both cardiovascular risk and phenotype among adult black Africans. However, specific thresholds need to be defined based on prospective studies.

Risk factors for stroke among patients with hypertension: a case-control study.

BACKGROUND: In some African countries, more than half of the adult population are estimated to be hypertensive leading to an escalated burden of stroke in the continent. We conducted the first study to unravel the major risk factors for stroke among hypertensive patients (Nigerian-Africans) using a case-control design while also exploring the relative contributions of carotid intima medial thickness (CIMT) and carotid diameter as risk markers for stroke. METHODS: Using conventional techniques, stroke-related demographic, clinical and laboratory data were obtained from 135 consecutive volunteering hypertensive stroke patients and compared with 117 age and gender-matched hypertensive patients with no clinical evidence of stroke, TIA or coronary artery disease. Common carotid IMT and diameters were measured in all participants. Univariate and multivariate analyses were conducted at p=0.05. RESULTS: 13.2% of the stroke patients were first diagnosed as hypertensive at presentation with stroke. Among hypertensive patients, the modifiable factors significantly (p<0.00001 to p<0.037) associated with stroke occurrence included higher maximum and minimum blood pressures in the preceding 3months, higher fasting plasma glucose, greater alcohol consumption, lesser physical activity and increased CIMT. Using a multivariate model which predicted 84.6% of stroke occurrence, only fasting total cholesterol of >150mg/dl (p=0.021) and common carotid diameter of ≥5.9mm (p=0.008) independently multiplied the risk of stroke. CONCLUSIONS: Particularly in resource-limited settings, aside from BP control, stroke prevention efforts should be targeted towards these identified risk factors for stroke among hypertensive patients. Carotid diameter should be further explored as an intermediate risk marker for stroke.

Racial disparity in stroke risk factors: the Berlin-Ibadan experience; a retrospective study.

BACKGROUND: Different workers have reported racial disparities in the distribution of risk factors for stroke and stroke subtype (ischemic vs hemorrhagic). No transcultural transnational studies have been conducted to confirm and relate these disparities to one another. Our objective was to identify differences in the distribution of risk factors for stroke and stroke subtypes among urban-dwelling stroke patients in Nigeria, a developing country, and Germany, an industrialized country. METHODS: Consecutive stroke patients in Ibadan (100) and Berlin (103) were studied. Their hospital records were screened to identify documented vascular risk factors and stroke subtype. RESULTS: The stroke patients in Ibadan were younger than those in Berlin (t = 4.940, P = 0.000). Hypertension was significantly more common in Ibadan while cigarette smoking, dyslipidemia, atherosclerosis, and cardiac factors were significantly more frequent in Berlin. Cerebral infarction was more common in Berlin (80%) than in Ibadan (63%). CONCLUSION: The risk factors associated with cerebral infarction were more frequent in Berlin. We suspect that racial disparity in risk factors for stroke may account for the difference in proportions of stroke subtype in black and white populations. Larger prospective community-based multinational multiracial studies are required to confirm these disparities and identify possible underlying genetic, dietary, and socio-economic factors.

Autoimmune diseases in a Nigerian woman--a case report.

Autoimmune diseases (AD) are conditions in which there is the development of antibodies against self cells/ organs. AD could either be organ-specific or non-organ specific (systemic) in clinical presentation. Commonly reported ADs includes: Myasthenia gravis, Hashimoto thyroiditis, Guillian-Barre syndrome, vitiligo, type 1 diabetes mellitus, Graves diseases, Goodpastures syndrome, pemphigus, rheumatoid arthritis, systemic lupus erythematosis, Addisons disease, multiple sclerosis, pernicious anaemia, autoimmune haemolytic anaemia, chronic active hepatitis, idiopathic thrombocytopenic purpura. There is paucity of locally documented information on the occurrence of AD in same patient in our environment. We therefore report the case of a 66 year old woman who presented at the University College Hospital (UCH), Ibadan, with a spectrum of the AD, Vitiligo, rheumatoid arthritis, myasthenia gravis, impaired glucose tolerance.