Characteristics and Predictors of Controlled Hypertension at A Tertiary Health Facility in Nigeria

Abstract

Aim: Our cross-sectional study set out to identify characteristics and predictors of hypertension control among adults on drug treatment. The aim was to provide current, actionable evidence of the factors that promote hypertension control and hence, improve health outcomes through reduction of cardiovascular morbidity and mortality.  Methods: We conducted a descriptive, cross-sectional, and hospital-based study of 90 eligible, previously diagnosed and currently treated adults (18 years or older) with hypertension at the Medical Outpatients’ Clinic of Igbinedion University Teaching Hospital, Benin City, Nigeria. Controlled hypertension was defined as systolic blood pressure <140 mm Hg and diastolic blood pressure <90 mm Hg, on treatment with antihypertensive medication. The distribution of characteristics of adults with controlled hypertension was summarized with descriptive analysis and the predictor of hypertension control investigated by fitting binary logistic regression model.  Results: Mean age of the adult study population was 58.34 years (SD 12.54, 95% CI 55.78 to 60.91). The majority were female (57.8%), married (76.7%), self-employed (64.4%), urban dwellers (73.3%) and all (100%) had at least primary school education. Almost two-thirds (65.6%) had never taken or had stopped taking alcohol, and none self-reported current smoking status. Some 62.2% had excess adiposity, 17.8% had diabetes and 40% had evidence of hypertensive target organ damage. Only 10% (95% CI 4.7%-18.1%) of patients had health insurance coverage. Mean systolic blood pressure was 138 mmHg (SD 21.71; 95% CI 133-142) while mean diastolic blood pressure was 86 mmHg (SD, 13.96; 95% CI, 83-89 mmHg). Slightly over half of the study population (n = 47; 52.2%, 95% CI 41.4%-62.9%) had controlled hypertension. The most frequently prescribed antihypertensive medication was calcium channel blocker (84.4%) either singly or in combination with other drug classes. Majority of the patients (n = 61, 67.8%) were on free-drug or fixed-dose combinations. Fifty-two patients (57.8%; 95% CI 46.9%-68.1%) had good adherence to prescribed antihypertensive medication. Apart from health insurance coverage and good adherence to medications, no other patients’ characteristics were significantly associated statistically, with controlled hypertension. The only independent predictor of controlled hypertension was good adherence to antihypertensive medication.  Conclusion: This study adds to the body of literature on hypertension control by shedding light on the attributes of adults with controlled hypertension. However, hypertension control to target among our study population was suboptimal. The salient evidence of gaps in hypertension control provided by this study should be regarded as an opportunity to review and adopt more effective patient-centered and health system-related hypertension control strategies. Wider health insurance coverage and interventions to boost patients’ adherence to components of hypertension management are strategies that could make a significant impact on health outcomes, if adequately and sustainably implemented.