The prevalence and incidence of tuberculosis (TB) is high among people living with HIV (PLWH) but is often underdiagnosed in HIV programmatic settings. As part of MHRP’s ongoing African Cohort Study (AFRICOS), researchers assessed the prevalence and incidence of HIV-TB among participants receiving services supported by the President’s Emergency Plan for AIDS Relief (PEPFAR) to identify factors associated with co-morbidity and better understand gaps in TB screening and diagnosis. Epidemiological findings from eight years of the AFRICOS study, from 2013 to 2021, were recently published in the Journal of Acquired Immune Deficiency Syndromes.
MHRP launched the AFRICOS study in 2013. This planned 15-year study takes place at research sites in Kenya, Nigeria, Tanzania and Uganda and examines current national treatment regimens and a range of outcomes, such as viral load and antiretroviral drug resistance. All four AFRICOS research countries ranked in the top 30 globally for HIV TB burden in 2021, according to the World Health Organization.
One of the strengths of AFRICOS is that researchers prospectively screen participants for co-morbidities and co-infections—including TB—over time regardless of symptoms. The prevalence and incidence of TB was notably high in the AFRICOS cohort. Using data from January 2013 to December 2021, the study found a TB prevalence of 3% in the 3,171 PLWH enrolled in AFRICOS.
The overall TB incidence rate was 600 per 100,000 person-years, which means there would be, on average, 600 new TB cases if 100,000 people in the cohort were observed for one year. More new TB cases occurring after enrollment in AFRICOS were associated with shorter time since HIV diagnosis (compared to those for whom it had been 5 or more years since their diagnosis), being underweight, taking antiretroviral therapy less than 6 months, and having a CD4 count <200 cells/mm3. Prescribed ART regimen was also linked to TB incidence; participants on dolutegravir/lamivudine/tenofovir had a 78% lower risk of incident TB compared with those on tenofovir/lamivudine/efavirenz.
Given these findings, researchers concluded early HIV diagnosis and immediate ART initiation among PLWH can reduce the risk of acquiring TB. Providers should ensure those newly diagnosed with HIV or newly in care are screened for TB with fidelity as these individuals have the highest TB prevalence in the study. There is still a need to scale-up and implement nutrition-based interventions to prevent and manage TB among PLWH.