Risk factors of heart failure among patients with hypertension attending a tertiary hospital in Ibadan, Nigeria: The RISK-HHF case-control study

Background: Hypertension is the leading cause of heart failure in sub-Saharan Africa. Preventive public health approach to reduce the scourge of HF must seek to understand the risk factors of heart failure in at risk populations. The aim of this study was to characterize the modifiable risk factors of HF among patients with hypertension attending a cardiology clinic. Methods: One hundred and one (101) case-control age- and sex-matched pairs were recruited. The study population were adults with a clinical diagnosis of hypertensive heart failure (cases) and hypertension. They were interviewed and evaluated for modifiable cardiovascular risk factors. Associations between variables were tested with McNemar’s chi square test and paired sample t test as appropriate. Conditional logistic regression modelling was used to determine the risk factors of HF in the study population while ‘punafcc’ package in stata15 was used to calculate the population attributable fraction (PAF) of risk factors. Results: Low education attainment ( aOR: 2.38, 95% CI: 0.91-6.20; PAF: 21.1%, 95% CI: 5.1-34.5 ) showed borderline association with HF while alcohol consumption (aOR: 10.40, 95% CI: 2.30-47.04; PAF: 33.5%, 95% CI: 21.6-43.6) and suboptimal medication adherence (aOR: 7.00, 95% CI: 2.31-21.26; PAF: 69.7%, 95% CI: 59.4-77.4) were strong risk factors for HF even after adjustment for other modifiable risk factors. These three dominant risk factors accounted for 89% of the PAF of HF. Dietary factors were not significantly associated with HF risk in adjusted analyses. Conclusions: The risk factors for heart failure in hypertensive patients are largely modifiable. Public health interventions and preventive cardiovascular care to improve medication adherence and reduce alcohol consumption among patients with hypertension are recommended.