Incidence and risk factors for tuberculosis at a rural HIV clinic in Uganda, 2012-2019; A retrospective cohort study

Background Tuberculosis (TB) is the leading cause of death among people living with HIV (PLHIV). Antiretroviral therapy (ART) initiation lowers the risk of HIV-associated TB. Earlier studies have shown TB incidence to be high in the first year of ART. We undertook a study to (1) assess the incidence of TB and (2) associated factors among persons initiating ART in a rural cohort. Methods We conducted a retrospective cohort analysis study among PLHIV aged ≥ 18 years, initiated on ART from January 1, 2012, to December 31, 2019, and TB disease-free at the time of ART initiation, at Kalisizo ART clinic. TB disease incidence was calculated by dividing the number of new TB cases by the total follow-up time expressed per 100 person-years among persons followed up until the date of incident TB disease, loss to follow-up, transfer out, death or censored at the end of the study; whichever occurred first. Factors associated with TB disease incidence were assessed in the multivariable analysis by Poisson regression analysis at 5% significance level. Results For the period 2012 to 2019, 2,589 PLHIV were initiated on ART; 57% (1,470/2,589) were female. Females were more likely to be aged below 35 years while males were more likely to be aged 25-44 years (p 24 months (adj IRR 0.20 (95% CI: 0.09-0.46), 0.14 (95% CI: 0.06-0.33), 0.16 (95% CI: 0.08-0.31) p Conclusions and recommendations Incidence of TB among PLHIV on ART was low in this rural population. Clinicians offering care to people with HIV in the rural setting should have a heightened index of suspicion for TB disease.