Reações adversas a medicamentos antirretrovirais em coorte histórica de pacientes acompanhados em serviço de assistência especializada a portadores do HIV e doentes de AIDS

Abstract

OBJECTIVE: A historical cohort study was conducted to describe the frequency and reason for the exchange of initial antiretrovirals schemes, analyze the exchanges due to adverse reactions and investigate the associated factors in patients who initiated therapy at a referral center for HIV/AIDS in Porto Alegre/RS, Brazil. METHODS: The study is part of a multicentric protocol where only data from Porto Alegre/RS were used. The study included 819 HIV-infected individuals that started antiretroviral therapy (ART) between 2003 and2010. Sociodemographic characteristics and clinical behavior were described. A Cox regression model was used to verify the association of study factors with the outcome. A Kaplan Meier curve was designed to evaluate the probability of being free from adverse reactions over time. RESULTS: The sample average age was 38 years, 53% were men, the majority had up to 4 years of education (48.6%) and reported infection by heterosexual contact (74.9%). Seventy percent had initial CD4 <250 cells/mm3 and 46.5% a viral load between 10000-99999 copies/mL. The scheme mostly used was AZT+3TC+EFV (56.8%). The median time to the shift of the first regimen was 34 weeks. In total there were 328 exchanges of the first scheme, 172 (52,4%) due to adverse reactions. The most common adverse reactions that led to the exchange were gastrointestinal symptoms (23%), anemia (19%), neuropsychiatric symptoms (14%) and dyslipidemia (11%). Factors independently associated with increased risk for exchange of the first scheme, were schooling between 5-8 years (HR 1.57 95% CI 1.11 to 2.22), use of regimens containing AZT + 3TC combined with a boosted PI (LOP/R [HR 1.95 95% CI 1.02 to 3.74] and ATZ/R [HR 3.32 95% CI 1.63 to 6.76) besides antiretrovirals classified as "other" (HR 3, 24 95% CI 1.36 to 7.78), which are currently unused. CONCLUSIONS: Adverse reactions caused by antiretrovirals were the main reason for changing the first treatment schema and may impair the treatment outcome. The choice of treatment and individual close monitoring are conditions that should receive special attention, thus seeking to avoid disruptions and exchanges which, if not properly managed, can contribute to the therapeutic failure.