Medication Adherence and Blood Pressure Control Among Hypertensive Outpatients Attending a Tertiary Cardiovascular Hospital in Tanzania: A Cross-Sectional Study

Pedro Pallangyo; Makrina Komba; Zabella S Mkojera; Peter R Kisenge; Smita Bhalia; Henry Mayala; Engerasiya Kifai; Mwinyipembe K Richard; Khuzeima Khanbhai; Salma Wibonela; Jalack Millinga; Robert Yeyeye; Nelson F Njau; Thadei K Odemary; Mohamed Janabi

doi:10.2147/IBPC.S374674

Medication Adherence and Blood Pressure Control Among Hypertensive Outpatients Attending a Tertiary Cardiovascular Hospital in Tanzania: A Cross-Sectional Study

Integr Blood Press Control. 2022 Aug 10:15:97-112. doi: 10.2147/IBPC.S374674. eCollection 2022.

Authors

Pedro Pallangyo^{1

2}, Makrina Komba¹, Zabella S Mkojera¹, Peter R Kisenge^{1

2}, Smita Bhalia², Henry Mayala³, Engerasiya Kifai³, Mwinyipembe K Richard², Khuzeima Khanbhai^{1

2}, Salma Wibonela⁴, Jalack Millinga⁴, Robert Yeyeye⁴, Nelson F Njau³, Thadei K Odemary³, Mohamed Janabi²

Affiliations

¹ Unit of Research and Training, Jakaya Kikwete Cardiac Institute, Dar es Salaam, Tanzania.
² Directorate of Cardiology, Jakaya Kikwete Cardiac Institute, Dar es Salaam, Tanzania.
³ Directorate of Clinical Support Services, Jakaya Kikwete Cardiac Institute, Dar es Salaam, Tanzania.
⁴ Directorate of Nursing, Jakaya Kikwete Cardiac Institute, Dar es Salaam, Tanzania.

Abstract

Background: Notwithstanding the availability of effective treatments, asymptomatic nature and the interminable treatment length, adherence to medication remains a substantial challenge among patients with hypertension. Suboptimal adherence to BP-lowering agents is a growing global concern that is associated with the substantial worsening of disease, increased service utilization and health-care cost escalation. This study aimed to explore medication adherence and its associated factors among hypertension outpatients attending a tertiary-level cardiovascular hospital in Tanzania.

Methods: The pill count adherence ratio (PCAR) was used to compute adherence rate. In descriptive analyses, adherence was dichotomized and consumption of less than 80% of the prescribed medications was used to denote poor adherence. Logistic regression analyses was used to determine factors associated with adherence.

Results: A total of 849 outpatients taking antihypertensive drugs for ≥1 month prior to recruitment were randomly enrolled in this study. The mean age was 59.9 years and about two-thirds were females. Overall, a total of 653 (76.9%) participants had good adherence and 367 (43.2%) had their blood pressure controlled. Multivariate logistic regression analysis showed; lack of a health insurance (OR 0.5, 95% CI 0.3-0.7, p<0.01), last BP measurement >1 week (OR 0.6, 95% CI 0.4-0.8, p<0.01), last clinic attendance >1 month (OR 0.4, 95% CI 0.3-0.6, p<0.001), frequent unavailability of drugs (OR 0.6, 95% CI 0.3-0.9, p = 0.03), running out of medication before the next appointment (OR 0.6, 95% CI 0.4-0.9, p = 0.01) and stopping medications when asymptomatic (OR 0.6, 95% CI 0.4-0.8, p<0.001) to be independent associated factors for poor adherence.

Conclusion: A substantial proportion of hypertensive outpatients in this tertiary-level setting had good medication adherence. Nonetheless, observed suboptimal blood pressure control regardless of a fairly satisfactory adherence rate suggests that lifestyle modification plays a central role in hypertension management.

Keywords: blood pressure control; drug adherence; hypertension; medication adherence; nonadherence.

Grants and funding

This work was funded by PedPal Research Initiative. The funder had no role in the design of this study, collection of data, data analysis, interpretation of results or writing of this manuscript.