Impact of Persistent Organic Pollutants on AIDS progression and all-cause mortality. A longitudinal study in HIV-2 infected individuals in Guinea-Bissau

Abstract

Background: Persistent organic pollutants (POPs) may be harmful to human health. In a previous study we found high levels of organochlorine (OC) pesticides in an occupational cohort in Guinea-Bissau. We investigated if POP levels in serum were associated with clinical progression to AIDS and mortality in individuals infected with HIV-2, an AIDS-causing virus that is circulating in West Africa. Methods: We selected HIV-2 infected individuals entering an open prospective cohort of police officers in Guinea-Bissau between 1990 and 1996, who progressed to AIDS within five years after inclusion (progressors, n=30). For comparison, HIV-2 infected individuals without AIDS during at least five years of follow-up were selected (non-progressors, n=52). Biobanked sera were analysed for 22 POPs, including OC pesticides and polychlorinated biphenyls (PCB). Associations of individual POP concentrations with the development of AIDS within 5 years were first evaluated with logistic regression adjusted for age and sex. Cox proportional hazard models adjusting for age and sex were then used to determine associations between POPs and progression to AIDS or all-cause mortality during prolonged follow-up that continued until 2013. Results: High serum levels of OC pesticides were detected at cohort entry. The development of AIDS was not related to baseline serum POP levels. During prolonged follow-up, 58 individuals developed AIDS (71%) and 53 died (65%). An increased risk for all-cause mortality was observed for beta- hexachlorocyclohexane (HR 1.35, 95%CI 1.01-1,82), p,p´-DDT (HR 1.32, 95%CI 0.99-1.77) and p,p´-DDE (HR 1.34, 95%CI 0.99-1.81). Eight PCBs were also evaluated without any association with development of AIDS or all-cause mortality. Conclusions: An association was indicated between higher levels of OC pesticides and increased all-cause mortality risk, but not with progression to AIDS among HIV-2 infected individuals in Guinea-Bissau, West Africa. Our results reinforce that public health actions should be considered to minimize exposure to OC pesticides.