Factors associated with adherence to antiretroviral therapy in HIV/AIDS patients: a cross-sectional study in Southern Brazil

RESUMO

A cross-sectional study was conducted on HIV-infected adults being treated with antiretroviral drugs at a reference service in Southern Brazil. Participants answered a sociodemographic questionnaire and were tested by scales assessing sociocognitive variables. Adherence to treatment was assessed by a self-report inventory developed for the study. Clinical information was obtained from the patients' records. Significance tests were conducted using univariate logistic regressions followed by multivariate logistic regression analysis. A total of 195 patients participated in the study and 56.9 percent of them reported > or = 95 percent adherence on the previous two days. In univariate analysis, the odds of adherence increased with self-efficacy (a person's conviction that he/she can successfully execute the behavior required to produce a certain desired outcome) in taking medications as prescribed (OR = 3.50, 95 percent CI 1.90-6.55), and decreased with perception of negative affect and physical concerns (OR = 0.71, 95 percent CI 0.53-0.95). The odds were lower for taking antiretroviral medications >4 times a day (OR = 0.44, 95 percent CI 0.20-0.94) and higher for patients with 8 years of schooling (OR = 2.28, 95 percent CI 1.12-4.66). In the multivariate analysis, self-efficacy (OR = 3.33, 95 percent CI 1.69-6.56) and taking medication >4 times a day (OR = 0.34, 95 percent CI 0.14-0.80) were independently associated with adherence. Self-efficacy was the most important predictor of adherence, followed by number of times antiretroviral medication was taken per day. Among sociodemographic and clinical variables, only the number of years of schooling was associated with adherence. Motivational interventions based on self-efficacy may be useful for increasing treatment adherence