Associação entre acesso livre aos medicamentos anti-hipertensivos e adesão terapêutica

Abstract

Often it is identified the cost of treatment as one of the main barriers to therapeutic adherence. The Unified Health System (SUS) has a coverage of 75% of the Brazilian population, and it has among its attributions to guarantee free access to essential medicines, eliminating an important barrier to the control of blood pressure (BP) in patients with hypertension. The objective of the present study is to evaluate the relationship between free access to antihypertensive drugs and therapeutic adherence. This is a cross-sectional study with patients with hypertension, over 18 years of age, attended at public and private community pharmacies in Maceió, Brazil, between January 2011 and December 2014. Patients were divided into two groups, according to the access to antihypertensive treatment: free access and paid access. The values of systolic BP and diastolic BP were obtained according to the 6th Brazilian Directive of Hypertension. Adhesion was determined using the MMAS-8 scale. The therapeutic adherence rate in the sample of 1228 patients included was 55.7%, with a BP control rate (<140/90 mmHg) of 44.1% among non-diabetic hypertensive patients and 8.0 % among patients with hypertension and diabetes (BP <130/80 mmHg). Therapeutic adherence was related to BP control in non-diabetic patients (p = 0.005); however, among patients with diabetes, this relation was not observed (p = 0.099). Being over 60 years old (p = 0.007), not having a low level of education (p = 0.006) and practicing physical activity (p = 0.001) were some of the factors associated with a higher degree of adherence. The rate of adherence among patients with paid access was 60.8%, against 53.7% among patients with free access to medication (p = 0.026). Both hypertensive patients without diabetes and those with diabetes with paid access to their antihypertensive treatments had higher BP control rates (p = 0.000 and p = 0.007, respectively). After analysis by logistic regression, it was observed that monotherapy and low schooling were related to low adherence, while physical activity and being over 60 years old were factors related to adherent behavior. It should, it was noted that free access to medication was not associated with better therapeutic adherence. However, among the low-income population, free access corresponded to the only access route to antihypertensive treatments. Monotherapy was the factor with the greatest strength of association with low adherence. The results of the present study indicate that greater knowledge of the therapeutic scheme and higher educational level of the patients are the main contributing factors for therapeutic adherence.