Cotrimoxazole prophylaxis for people with HIV reduces illness and death in other family members too

Cotrimoxazole prophylaxis appears to provide an indirect benefit to HIV-negative members of the household if an HIV-positive person is taking it, a prospective study from Uganda shows. The findings, published in the July 1^st edition of the journal AIDS, show that children under the age of ten were nearly two-thirds less likely to die if a family member was receiving cotrimoxazole; all family members were less likely to become sick or die, and malarial parasitamia declined among HIV-negative family members too.

Cotrimoxazole prophylaxis is recommended by the World Health Organization (WHO) for all HIV-positive adults with CD4 cell counts below 500 cells/mm³ in resource-limited settings; for children with signs or symptoms of HIV disease, and for all potentially HIV-exposed infants up to the age of 18 months. It is intended to prevent bacterial infections and Pneumocystis pneumonia (PCP). Cotrimoxazole prophylaxis has been shown to dramatically reduce the risk of illness and death in HIV-positive adults and children.

Investigators in Uganda recruited a cohort of HIV-positive individuals and their households through AIDS support group TASO. A total of 879 people with HIV and 2771 HIV-negative family members were identified and followed for at least a year through weekly home visits. After five months of follow-up, HIV-positive family members who knew their HIV status were provided with cotrimoxazole prophylaxis. The five month period without prophylaxis was designed to allow a comparison in rates of illness and death between periods with and without prophylaxis, and was approved by ethics committees in Uganda and the United States.

A comparison between death rates in the prophylaxis and pre-prophylaxis periods showed HIV-negative family members below the age of ten had a mortality rate that was 63% lower during the prophylaxis period (hazard ratio 0.37, 95% confidence interval 0.14-095, p = 0.04). A similar effect was not seen in older family members. Nine of 22 children below the age of ten died after an HIV-positive parent, reinforcing the view that young children of HIV-positive parents are highly vulnerable after a parent’s death. “For 90% of children in our population, all living parents had HIV”, the authors report.

The incidence of malaria also declined during the prophylaxis period, from 37 to 22 episodes per 100 person years (incidence rate ratio 0.62, CI 0.53-0.74, p

Episodes of diarrhoea among HIV-negative family members declined by 41% and hospitalisation by 43% during the prophylaxis period.

Antimicrobial resistance in pathogens isolated from the stools of family members with diarrhoea did not increase during the prophylaxis period, suggesting that cotrimoxazole prophylaxis does not result in the transmission of drug-resistant microbes to other family members at a higher rate.

The authors note: “Prolonging the lives of persons with HIV…could have a profound impact on the incidence of orphans. In addition, preventing illness and mortality among persons with HIV may improve health and longevity of their family members.”