Incidence and Determinants of Tuberculosis among Adults Initiating Antiretroviral Therapy – Mozambique, 2004–2008

BACKGROUND In Mozambique, tuberculosis (TB) is thought to be the most common cause of death among antiretroviral therapy (ART) enrollees. Monitoring proportions of enrollees screened for TB, and incidence and determinants of TB during ART can help clinicians and program managers identify program improvement opportunities. METHODOLOGY/PRINCIPAL FINDINGS We conducted a retrospective cohort study among a nationally representative sample of the 79,500 adults (>14 years old) initiating ART during 2004-2007 to estimate clinician compliance with TB screening guidelines, factors associated with active TB at ART initiation, and incidence and predictors of documented TB during ART follow-up. Of 94 sites enrolling >50 adults on ART, 30 were selected using probability-proportional-to-size sampling; 2,596 medical records at these sites were randomly selected for abstraction and analysis. At ART initiation, median age of patients was 34, 62% were female, median baseline CD4(+) T-cell count was 153/µL, and 11% were taking TB treatment. Proportions of records with TB screening documentation before ART initiation improved from 31% to 66% during 2004-2007 (p<0.001). TB screening compliance varied widely by ART clinic [n = 30, 2%-98% (p<0.001)] and supporting non-Governmental Organization (NGO) [n = 7, 27%-83% (p<0.001)]. Receiving TB treatment at ART enrollment was associated with male sex (p<0.001), weight <45 kg (p<0.001) and CD4<50/µL (p = 0.001). Isoniazid preventive therapy (IPT) was prescribed to <1% of ART enrollees not taking TB treatment. TB incidence during ART was 2.32 cases per 100 person-years. Factors associated with TB incidence included adherence to ART <95% (AHR 2.06; 95% CI, 1.32-3.21). CONCLUSION Variations in TB screening by clinic and NGO may reflect differing investments in TB screening activities. Future scale-up should target under-performing clinics. Scale-up of TB screening at ART initiation, IPT, and ART adherence interventions could significantly reduce incident TB during ART.