Prevalence and Correlates of Medication Non-adherence among Hypertensive Patients on Follow-up in Central Kenya

Abstract

Background and Objective: Poor adherence to antihypertensive medications is a major barrier to blood pressure control among patients living with hypertension. In Kenya, a significant number of hypertensive patients have uncontrolled blood pressure, but data on medication adherence among this patient population is scarce. This study sought to determine the prevalence and correlates of medication non-adherence among hypertensive patients on follow-up in two referral hospitals in central Kenya. Methods: We undertook a cross-sectional study comprising of 339 hypertensive patients undergoing followup care in two referral hospitals located in Nyeri County between October and December 2019. Medication adherence was assessed using a validated medication adherence questionnaire. Medication adherence was a dichotomous variable (adherent vs non-adherent), with the prevalence of non-adherence being measured as a proportion. Independent predictors of medication non-adherence were identified by fitting a multiple logistic regression model, where adjusted odds ratios (AORs) were computed for various covariates and interpreted at a 5% level of significance and 95% confidence interval (CI). Results: The study sample largely comprised of the female gender (65.2%) and elderly people (mean age, 65 years +/- 12). Nearly half (46.6%) of the hypertensive patients interviewed were non-adherent to their medications. The factors associated with non-adherence were: having poor hypertension knowledge (AOR, 5.6, 95% CI, 3.3, 9.4); being on more than one antihypertensive medication (AOR, 2.8, 95% CI, 1.7, 4.7) and being on two or more daily doses of medications (AOR, 2.3, 95% CI, 1.3, 4.1). Conclusion and Implications for Translation: Non-adherence to prescribed medications is highly prevalent among hypertensive patients in central Kenya, and it should therefore be identified as a public health concern. Strategies aimed at optimizing medication adherence among hypertensive patients in this region may consider focusing on educational interventions to increase hypertension knowledge and also on simplification of treatment regimens.