RESUMO
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.
RESUMO
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.