Cotrimoxazole cuts TB incidence up to 30% in Swiss HIV Cohort Study

Mark Mascolini
March 26, 2014, 4:47 p.m.

Taking cotrimoxazole decreased tuberculosis incidence 13% to 30% in HIV-positive adults in Switzerland, depending on whether they were already taking antiretrovirals.

Cotrimoxazole lowers deaths rates in HIV populations with tuberculosis, and lab studies suggest that cotrimoxazole may have activity against Mycobacterium tuberculosis. The World Health Organization recommends cotrimoxazole for HIV-positive adults with a CD4 count below 350 cells/μL in resource-limited settings, continuing after people start antiretroviral therapy (ART).

To assess the impact of cotrimoxazole in HIV-positive adults in a high-income country, Swiss HIV Cohort Study (SHCS) researchers determined TB incidence from January 1992 to December 2012 in antiretroviral-naive people and people taking ART. The analysis adjusted for CD4 count, sex, region of origin, injection drug use, and age.

Among 13,431 SHCS members with 107,549 person-years of follow-up, TB developed in 182 people—132 (73%) who had not started ART and 50 (27%) who had.

Among people who had not started ART, taking cotrimoxazole lowered TB incidence 30% (incidence rate ratio 0.70, 95% confidence interval 0.55 to 0.89). Among people taking ART, cotrimoxazole cut TB incidence 13% (incidence rate ratio 0.87, 95% confidence interval 0.74 to 1.0).

The investigators propose that cotrimoxazole “may prevent the development of TB among HIV-positive persons, especially among those with no previous ART.”

Source: Barbara Hasse, A. Sarah Walker, Jan Fehr, Hansjakob Furrer, Matthias Hoffmann, Manuel Battegay, Alexandra Calmy, Jacques Fellay, Caroline Di Benedetto, Rainer Weber, Bruno Ledergerber, the Swiss HIV Cohort Study. Co-trimoxazole prophylaxis is associated with reduced risk of incident tuberculosis in participants in the Swiss HIV Cohort Study. Antimicrobials Agents and Chemotherapy. 2014 ; 58: 2363-2368.

For the study abstract

(Downloading the complete article requires a subscription to Antimicrobials Agents and Chemotherapy or an online payment; the abstract is free.)

For WHO cotrimoxazole guidelines

Source: IAS