Blood pressure-lowering medication prescribing, its adherence to guidelines and relationship with blood pressure control at a family medicine department.

Abstract

In many resource-constrained countries, control of blood pressure (BP) is low. Antihypertensive drug prescribing practices may influence BP control. However, adherence of prescribing to treatment guidelines may not be optimal in resource-constrained settings. The aim of this study was to evaluate the pattern of blood pressure-lowering medication prescribing, and how it adheres to treatment guidelines, and to identify the relationship between medication prescriptions and BP control. It was a cross-sectional study of hypertensive outpatients at the Korle Bu Teaching Hospital (KBTH) Family Medicine department (FMD)/Polyclinic. Data was collected with a validated structured form. Adherence of "prescribing" to recommendations of the 2017 Standard Treatment Guidelines of Ghana and 2018 European Society of Cardiology guidelines was assessed using a composite measure. We analyzed data with SPSS. About 81% (247/304) of patients received two or more antihypertensive drugs. Most patients (41%; 267/651) received calcium channel blockers (CCB), and 21.8% (142/651), 15.7% (102/651) and 12.7% (83/651) were on diuretics, angiotensin-receptor blockers (ARBs) and angiotensin converting enzyme (ACE) inhibitors respectively. CCB plus RAS inhibitor (50%) was the most prescribed two-drug combination. Number of BP drugs per patient had a statistically significant inverse relationship with BP control (beta Coefficient = -0.402; 95% Cl: 1.252-2.470; p = 0.015). The composite adherence score was 0.73 (moderate adherence) but Single-pill combination (SPC) was poor (3.2%; n = 8). Most patients received multiple-pill combination treatment, and overall adherence to guidelines was suboptimal, largely owing to complex drug therapy. Number of drugs predicted BP control. Our findings suggest a need to prioritize simplified treatment, and implement other strategies to improve hypertension guideline adherence. Further research on the influence of SPC on BP control may inform future hypertension guidelines in Ghana and elsewhere in Africa.