Risk factors associated with non-adherence to anti-hypertensive medication among patients treated in family health care facilities

In order to estimate the prevalence of treatment non-adherence and associated factors among individuals with systemic arterial hypertension treated at family health care facilities, a cross-sectional study was performed with 595 patients. The dependent variable non-adherence was measured with a Medication Adherence Questionnaire (MAQ). A hierarchical logistic regression model was used to analyze socioeconomic, health care-related, personal, and treatment-related variables. Prevalence of non-adherence was 53%. Variables associated with non-adherence were: (1) socioeconomic - belonging to economic classes C, D, or E; work market participation in unskilled labor; (2) health care - out-of-pocket payment for medication; more than six months since last physician consultation; and (3) personal and treatment characteristics - previous interruption of treatment; being on treatment for less than three years; and presence of a common mental disorder. The study of determinants of non-adherence articulated in a hierarchical model suggests that social inequalities are either directly associated with non-adherence or mediated by personal and health services factors.