ABSTRACT
Background: Heart failure (HF) is a growing public health concern with a high mortality rate in sub-Saharan Africa. However, few studies have reported the long-term predictors of mortality in this region. This study sought to determine the 3-year mortality rate and the predictors of mortality amongst HF patients in Douala, Cameroon. Methods: We conducted a prospective analysis on patients recruited in the Douala Heart Failure (Do-HF) registry, an ongoing prospective data collection on patients with HF at four cardiology units in Douala, Cameroon. Patients included were followed for 36 months from the index date of inclusion, with all-cause mortality as the primary outcome. Cox proportional hazard regression models were used to determine predictors of mortality. Results: Out of the 347 participants included, 318 (91.6%) completed follow-up. The mean age was 64±14 years, 172 (49.6%) were men. Hypertensive cardiomyopathy and dilated cardiomyopathy were the most frequent causes of heart failure. The median follow-up was 33 months, and 150 (47.2%) patients died. Independent predictors of mortality included New York Heart Association functional class III & IV (aHR 2.23; 95% CI: 1.49-3.33; P<0.001), presence of pulmonary rales (aHR 1.87; 95% CI: 1.30-2.68; P=0.005), chronic kidney disease (aHR 2.92; 95% CI: 1.79-4.78; P<0.001), enrolment as inpatient (aHR1.96; 95% CI: 1.17-2.54; P=0.005), no formal education (aHR 2.06; 95% CI: 1.28-3.33; P=0.003), and a monthly income of at most three minimum wage (aHR 2.06; 95% CI: 1.28-3.33; P=0.003). Conclusions: This study shows that almost half of HF patients die after 36 months of follow-up. Also, late presentation and poverty-related conditions were associated with poor outcomes. These findings suggest prioritizing preventive strategies that target early diagnosis and socioeconomic status to improve the prognosis of HF.
ABSTRACT
INTRODUCTION: Several anthropometric measurements are variably recommended to assess adiposity in routine practice, with less agreement on their comparative performance. We assessed and compared the relationship of seven anthropometric measures of adiposity-waist circumference (WC), waist-to-height ratio (WHtR), Body Mass Index (BMI), Ponderal Index (PI), Conicity Index (C index), A Body Shape Index (ABSI), and Body Roundness Index (BRI)-with blood pressure (BP) levels and prevalent hypertension in adult Cameroonians. METHODS: Data were collected as Cameroon's contribution to the global May Measurement Month 2017(MMM17) survey. Participants were nonpregnant adults, who had no BP measurement in the past year and with no prior hypertension diagnosis. Hypertension was defined as systolic BP ≥140 mm Hg and/or diastolic ≥90 mm Hg. Odds ratios (ORs) for the presence of hypertension per 1 SD increase in each adiposity metrics were estimated in separate logistic regression models. Assessment and comparison of discrimination used the area under the receiver operating characteristics curve (AUC) and nonparametric methods. RESULTS: We included 14 424 participants (8210 [58.25%] female; 39.84 ± 14.33 years). There was a graded association between measures of adiposity and prevalent screen-detected (newly diagnosed) hypertension, with effect sizes being mostly within the same range across measures of adiposity. AUC for hypertension prediction ranged from 0.709 with PI to 0.721 with BRI for single measures, and from 0.736 to 0.739 with combinations of measures of adiposity. CONCLUSION: WC, WHtR, and BRI were strongly associated with BP and better predicted prevalent hypertension, with effects enhanced with the inclusion of BMI.
ABSTRACT
BACKGROUND: Higher resting heart rate (HR) is associated with mortality amongst Caucasians with heart failure (HF), but its significance has yet to be established in sub-Saharan Africans in whom HF differs in terms of characteristics and etiologies. We assessed the association of HR with all-cause mortality in patients with HF in sub-Saharan Africa. METHODS: The Douala HF registry (Do-HF) is an ongoing prospective data collection on patients with HF receiving care at four cardiac referral services in Douala, Cameroon. Patients included in this report were followed-up for 12 months from their index admission, for all-cause mortality. We used Cox-regression analysis to study the association of HR with all-cause mortality during follow-up. RESULTS: Of 347 patients included, 343 (98.8%) completed follow-up. The mean age was 64±14 years, 176 (50.7%) were female, and median admission HR was 85 bpm. During a median follow-up of 12 months, 78 (22.7%) patients died. Mortality increased steadily with HR increase and ranged from 12.2% in the lower quartile of HR (≤69 bpm) to 34.1% in the upper quartile of HR (>100 bpm). Hazard ratio of 12-month death per 10 bpm higher HR was 1.16 (1.04-1.29), with consistent effects across most subgroups, but a higher effect in participants with hypertension vs. those without (interaction P=0.044). CONCLUSIONS: HR was independently associated with increased risk of all-cause mortality in this study, particularly among participants with hypertension. The implication of this finding for risk prediction or reduction should be actively investigated.
ABSTRACT
BACKGROUND: Left atrial remodelling (LAR) has been described in Western populations with chronic hypertension and is associated with a higher risk of adverse cardiovascular events. Although hypertension tends to occur earlier and is more severe in sub-Saharan Africa than in more developed nations, LAR and its associated factors in these African hypertensive subjects have been poorly elucidated. OBJECTIVES: To assess left atrial structural remodelling in black hypertensive patients and determine factors associated with left atrial size. METHODS: This was a cross-sectional, comparative study carried out in two tertiary hospitals in Douala, Cameroon over a period of three months. Fifty-two patients, either newly diagnosed with hypertension or known hypertensives treated for less than a year, were consecutively recruited. These patients were matched (unpaired matching) for age and gender to 40 randomly selected healthy subjects. The posterior-anterior diameter indexed to body surface area (BSA), volume indexed to BSA, and longitudinal and transverse diameters of the left atrium (LA) were measured using transthoracic echocardiography, in accordance with the American Society of Echocardiography guidelines. LAR was defined as increase in LA size, characterised by LA volume ≥ 34 ml/m2. Early morning urine was analysed for microalbuminuria using urine strips to obtain spot albumin/creatinine ratio. Data were analysed using SPSS version 23 and statistical significance was set at p < 0.05. RESULTS: The gender distribution and mean age were similar between the two groups. Hypertensive patients had significantly higher mean body mass index, left ventricular mass and an altered diastolic function. They also had significantly higher LA longitudinal diameter (50.0 vs 47.4 mm; p = 0.045), surface area (17.9 vs 15.5 cm2; p = 0.003) and volume (52.4 vs 43.8 ml; p = 0.002) compared to the non-hypertensive counterparts. Fourteen patients (26.9%) had LA enlargement compared to one (2.5%) in the non-hypertensive group (odds ratio = 9.78, CI: 2.67-35.8, p < 0.0001). Diastolic dysfunction (p = 0.008) was the only independent predictor of LA size in the hypertensive subjects. Microalbuminuria did not significantly correlate with LA size. CONCLUSIONS: Our study shows evidence of LAR in newly diagnosed black African patients with hypertension, characterised by an increase in the LA length, surface area and volume. Future studies are warranted to better elucidate the biological mechanisms underlying the link between the early phase of hypertension and LAR, as well as its prognostic implications in our population.
