A Multi-Component Intervention to Improve Therapeutic Adherence in Uncontrolled Hypertensive Patients Within the Primary Care Level: A Before-and-After Study

Introduction Non-adherence to medication severely affects chronic disease control. Aim To assess whether a multi-component intervention implemented at the public primary care level in Argentina improves adherence to antihypertensive medication and helps to reduce blood pressure (BP) levels in uncontrolled hypertensive patients. Methods A before-and-after study was conducted in five public primary care clinics located in the city of Almirante Brown, Argentina. One hundred and twenty-five uncontrolled hypertensive patients received a multi-component intervention based on the Chronic Care model and the 5As strategy (Ask, Advise, Agree, Assist, and Arrange). Medication possession ratio (MPR) and BP values were assessed before and after a 6-month period. Results The follow-up rate was 96.8%. Main baseline characteristics were as follows, male: 44.8%, mean age: 57.1 years (+/- 8.1), exclusive public healthcare coverage: 83.5%, primary school level or less: 68.8%, and mean systolic/diastolic BP: 157.4 (+/- 13.6)/97.7 (+/- 8.2) mmHg. After implementing the intervention, a significant increase in the proportion of adequate adherence (MPR >= 80%) was observed, from 16.8% at baseline to 47.2% (p < 0.001). A significant reduction of 16.4 mmHg (CI 95%: 19.6, 13.1) was observed for systolic blood pressure (SBP) and 12.0 mmHg (CI 95%: 14.2, 9.9) for diastolic blood pressure (DBP) (p < 0.001). At 6 months, 51.2% of the population achieved blood pressure control (SBP < 140 mmHg and DBP < 90 mmHg). Conclusions The study intervention was associated with an increased adherence rate, achieving a significant reduction in BP values and reaching BP control in more than half of the population.