Effect of cotrimoxazole prophylaxis on malaria occurrence among HIV-infected adults in West Africa: The MALHIV Study.

IntroductionCotrimoxazole (CTX) should be given to all HIV-infected adults with mild or severe HIV-disease or those with CD4 counts below 350/mm(3) according to 2006 WHO guidelines. We assessed the impact of CTX prophylaxis on the risk of malaria episodes in HIV-1-infected adults from four West African countries with different patterns of malaria transmission. MethodMulticentric cohort study, conducted between September 2007 and March 2010 in four West African cities. Antiretroviral therapy (ART) naive HIV-infected adults started CTX at enrolment (CTX group) if they had CD4 < 350 cells/mm(3) or were at WHO clinical stage 2. For patients who did not start CTX at enrolment (non-CTX group) and started CTX afterwards, follow-up was censored at CTX initiation. We used Cox's proportional hazard model to compare the risk of malaria between CTX groups. ResultsA total of 514 participants (median CD4 count 238 cells/mm(3)) were followed for a median of 15 months. At enrolment, 347 started CTX, and 261 started ART. During the follow-up, 28 started CTX. The incidence of malaria was 8.7/100 PY (95%CI 6.3-11.5) overall, 5.2/100 PY (95%CI 3.1-8.3) in the CTX group and 15.5/100 PY (95%CI 10.3-22.1) in the non-CTX group. In multivariate analysis, CTX led to a 69% reduction in the risk of malaria (aHR 0.31, 95%CI 0.10-0.90). ConclusionPatients in the CTX group had an adjusted risk of malaria three times lower than those in the non-CTX group. The prolonged large-scale use of CTX did not blunt the efficacy of CTX to prevent malaria in this region.