Abstract
Background: The prevention of hypertension-related complications is a major goal of antihypertensive therapy. While there is generally a significant reduction of blood pressure (BP) upon initiation of drug therapy, there are reported challenges with the long-term sustenance of blood pressure control over time. This study therefore aimed to evaluate the effectiveness of antihypertensive therapy in BP control among patients on long-term therapy and its sociodemographic determinants.
Methods: This was an observational cohort study involving 125 subjects recruited from among hypertensive patients receiving care at a tertiary healthcare facility. Patients who were ≥ 30 years of age and have been receiving therapy for at least four months participated in the study. The enrolees were followed up for six months on existing antihypertensive drug(s) and the BP control target was set at 140/90mm/Hg. Data was collected during physician consultations and analysed with SPSS version 21 using descriptive and inferential statistics. The chi-square test was used to determine the association between sociodemographic variables and achievement of the BP control target. P values ≤ 0.05 were considered statistically significant.
Results: The results showed that while patients on monotherapies achieved 63.9% and 88.1% of systolic blood pressure (SBP) and diastolic Blood pressure (DBP) targets respectively, those on dual therapies achieved 57.5% and 84% SBP and DBP target respectively. Several factors including long duration of therapy (P = 0.052) and high body mass index (BMI), (P = 0.016) were found to be significantly associated with the achievement of BP control targets. It was also observed that there were slightly more subjects on monotherapies who achieved BP control targets (76%) compared to those on dual therapies (72%).
Conclusion: Antihypertensive therapies remain effective in long term BP control, however monotherapies achieved slightly better outcome compared to dual therapies. It is clear that failure to achieve and sustain BP control over time should be an important consideration in drug selection and pharmaceutical care interventions.
Keywords: Antihypertensives, Blood pressure control, Dual therapy, long-term therapy, Monotherapy