Prevalence, incidence and mortality associated with tuberculosis in HIV-infected patients initiating antiretroviral therapy in rural Uganda

Abstract
Tuberculosis (TB) is the leading cause of death among people with HIV in sub-Saharan Africa. Expanding access to antiretroviral therapy (ART) may reduce the burden of TB, but to what extent is unknown. In a study of 1044 adults who initiated home-based ART in Tororo, Uganda between 1 May 2003 and 30 June 2005, participants were screened for active TB at baseline and then monitored at weekly home visits. Participants with TB at baseline or follow-up were compared with those without TB to determine factors associated with mortality in those with TB. At baseline, 75 (7.2%) subjects had TB and a total of 53 (5.5%) were diagnosed with TB over a median of 1.4 years of follow-up (3.90 cases/100 person years). Cumulative mortality was 17.9/100 person-years for those with TB and 3.8/100 person-years for those without TB (P < 0.001). Mortality was associated with low baseline CD4 cell counts [relative hazard (RH), 0.99 per 1 cell/μl increase; P = 0.03] and marginally associated with a body mass index ≤ 18 (RH, 2.04; P = 0.10) and increasing age (RH, 1.04 per year; P = 0.11). TB incidence and TB-associated mortality were highest within the first 6 months of ART and declined to 52% and 61% of expected values, respectively, from months 7 to 18 after ART initiation. TB remains an important cause of illness and death in patients receiving ART in Uganda. However, both appear to decline markedly, after 6 months of ART.