11 research outputs found
Genetic mutations in African patients with atrial fibrillation: Rationale and design of the Study of Genetics of Atrial Fibrillation in an African Population (SIGNAL)
BACKGROUND:
There is an urgent need to understand genetic associations with atrial fibrillation in ethnically diverse populations. There are no such data from sub-Saharan Africa, despite the fact that atrial fibrillation is one of the fastest growing diseases. Moreover, patients with valvular heart disease are underrepresented in studies of the genetics of atrial fibrillation.
METHODS:
We designed a case-control study of patients with and without a history of atrial fibrillation in Kenya. Cases with atrial fibrillation included those with and without valvular heart disease. Patients underwent clinical phenotyping and will have laboratory analysis and genetic testing of >240 candidate genes associated with cardiovascular diseases. A 12-month follow-up assessment will determine the groups' morbidity and mortality. The primary analyses will describe genetic and phenotypic associations with atrial fibrillation.
RESULTS:
We recruited 298 participants: 72 (24%) with nonvalvular atrial fibrillation, 78 (26%) with valvular atrial fibrillation, and 148 (50%) controls without atrial fibrillation. The mean age of cases and controls were 53 and 48 years, respectively. Most (69%) participants were female. Controls more often had hypertension (45%) than did those with valvular atrial fibrillation (27%). Diabetes and current tobacco smoking were uncommon. A history of stroke was present in 25% of cases and in 5% of controls.
CONCLUSION:
This is the first study determining genetic associations in valvular and nonvalvular atrial fibrillation in sub-Saharan Africa with a control population. The results advance knowledge about atrial fibrillation and will enhance international efforts to decrease atrial fibrillation-related morbidity
Circulating plasma NT-proBNP predicts subclinical coronary atherosclerosis on CT angiography among older adults in Uganda
Abstract Objective Phenotypes and mechanisms of cardiovascular disease (CVD) may differ across global populations. In sub-Saharan Africa (SSA), distinct environmental determinants may influence development and progression of atherosclerotic coronary artery disease (CAD). Methods We investigated associations between 6 established markers of myocardial stress and subsequent subclinical CAD (sCAD), defined as presence of any atherosclerosis on coronary CT angiography (CCTA) in a 2-year prospective cohort of Ugandan adults enriched for cardiometabolic risk factors (RFs) and HIV. Six plasma biomarkers were measured baseline among 200 participants (50% with HIV) aged ≥ 45 years with ≥ 1 cardiovascular RF. At 2-year follow-up, 132 participants (52% with HIV) who returned underwent coronary CCTA. Results In logistic regression models adjusted for cardiovascular RFs (age, diabetes, hypertension, hyperlipidemia, smoking, obesity) and non-traditional RFs (HIV, chronic kidney disease), only NT-proBNP predicted subsequent subclinical CAD (p < 0.008, Bonferroni correction for multiple testing). In sensitivity analyses adjusted for ASCVD risk category (instead of individual RFs) in the baseline cohort with multiple imputation applied to missing year 2 CCTA data (n = 200), NT-proBNP remained significantly associated with subsequent CAD (p < 0.008). Conclusions NT-proBNP consistently predicted subclinical CAD in Uganda in the absence of such an association among other markers of myocardial stress, suggesting a role for NT-proBNP in atherosclerosis independently of coronary microvascular dysfunction
Clinical characteristics and 12-month outcomes of patients with valvular and non-valvular atrial fibrillation in Kenya
Background: Atrial fibrillation (AF) is a major contributor to the global cardiovascular disease burden. The clinical profile and outcomes of AF patients with valvular heart diseases in sub-Saharan Africa (SSA) have not been adequately described. We assessed clinical features and 12-month outcomes of patients with valvular AF (vAF) in comparison to AF patients without valvular heart disease (nvAF) in western Kenya. Methods: We performed a cohort study with retrospective data gathering to characterize risk factors and prospective data collection to characterize their hospitalization, stroke and mortality rates. Results: The AF patients included 77 with vAF and 69 with nvAF. The mean (SD) age of vAF and nvAF patients were 37.9(14.5) and 69.4(12.3) years, respectively. There were significant differences (p<0.001) between vAF and nvAF patients with respect to female sex (78% vs. 55%), rates of hypertension (29% vs. 73%) and heart failure (10% vs. 49%). vAF patients were more likely to be taking anticoagulation therapy compared to those with nvAF (97% vs. 76%; p<0.01). After 12-months of follow-up, the overall mortality, hospitalization and stroke rates for vAF patients were high, at 10%, 34% and 5% respectively, and were similar to the rates in the nvAF patients (15%, 36%, and 5%, respectively). Conclusion: Despite younger age and few comorbid conditions, patients with vAF in this developing country setting are at high risk for nonfatal and fatal outcomes, and are in need of interventions to improve short and long-term outcomes
Flow diagram of enrollment and12-months follow-up.
<p>Legend. AF = atrial fibrillation, LTFU = lost to follow up.</p
Medication use before study entry for atrial fibrillation patients.
<p>Medication use before study entry for atrial fibrillation patients.</p
Baseline characteristics of atrial fibrillation patients.
<p>Baseline characteristics of atrial fibrillation patients.</p
Comparison of outcomes of atrial fibrillation patients.
<p>Comparison of outcomes of atrial fibrillation patients.</p