Screening, preventive antibiotics lowered TB, mortality risk in patients with HIV

A community health program that included tuberculosis screening and isoniazid therapy for patients with HIV reduced the incidence of both tuberculosis and death, according to an international research team.

"Our study results show that routine testing for TB and preventive isoniazid therapy works well at the community level in people with HIV disease in curbing the spread of TB and lowering the number who die," study researcher Richard Chaisson, MD, director, Center for Tuberculosis Research at Johns Hopkins University, said in a press release.

Richard Chaisson

Chaisson and colleagues performed a cluster-randomized trial that included 12,816 patients aged 16 to 84 years who visited one of 29 HIV clinics across Brazil. All clinics were selected at random times to implement an intervention that included training staff to screen HIV-infected patients for TB, provide tuberculin skin tests and treat latent TB infection with isoniazid (300 mg daily for 6 months).

During the study, 475 patients developed TB and 838 died. The intervention resulted in a significant increase of patients receiving skin tests, from 19 per 100 person-years to 59 per 100 person-years (P<.0001). Among those who were eligible to receive isoniazid therapy, the rate increased from 36 per 100 person-years to 144 per 100 person-years (P<.0001).

In unadjusted analyses, the intervention led to a 24% (HR=0.76; 95% CI, 0.66-0.87) reduction in TB or death, and a 13% (HR=0.87; 95% CI, 0.69-1.1) reduction in new TB cases alone. However, controlling for clinical characteristics such as age, sex, CD4 count and the use of ART, the researchers observed a 31% (adjusted HR=0.69; 95% CI, 0.57-0.83) reduction in TB or death, and a 27% (adjusted HR=0.73; 95% CI, 0.54-0.99) reduction in new TB cases.

When the analyses were limited to patients who remained in contact with the clinic, there was a 55% (adjusted HR=0.45; 95% CI, 0.35-0.56) reduction in TB or death and a 58% (adjusted HR=0.42; 95% CI, 0.29-0.60) reduction in active TB cases.

The researchers also said initial TB screening as part of the intervention resulted in the diagnosis of 250 (34%) of the 725 patients found to have TB. These patients were excluded from the analyses, however.

Study researcher Jonathan Golub, PhD, MPH, an epidemiologist at Johns Hopkins, said the results underscore the effectiveness of TB screening in community health programs such as the one featured in the study.

Jonathan Golub

"Our study shows that HIV-infected patients will benefit if they are screened for active and latent tuberculosis and appropriately treated, and that these individual benefits can have an impact on disease and mortality in the HIV population as a whole," Golub told Infectious Disease News.

In an accompanying editorial, Molebogeng Xheedha Rangaka, MD, and Robert John Wilkinson, PhD, FRCP, of the Institute of Infectious Disease and Molecular Medicine, said despite some study limitations and the "modest effect" of the intervention, the results show that "tuberculosis or death in people with HIV could be reduced through policies that introduce isoniazid preventive therapy with complementary strategies in the context of reforms to modify social determinants of health."

For more information:

Durovni B. Lancet Infect Dis. 2013;doi:10.1016/S1473-3099(13)70187-7.

Rangaka MX. Lancet Infect Dis. 2013;doi:10.1016/S1473-3099(13)70218-4.

Jonathan Golub, PhD, MPH, can be reached at 1550 Orleans Street, Baltimore, MD, 2132; email: jgolub@jhmi.edu.

Disclosure: The researchers report no relevant financial disclosures.