Prevalence of Active Tuberculosis in People Living with HIV

On enrollment and at subsequent visits every 6 months, PLWH completed a physical examination, medical history, sociodemographic questionnaire, TB symptom screening, and phlebotomy. Participants were classified as having a history of TB if they had a TB diagnostic WHO code abstracted from their medical records before enrollment. Demographic variables collected include sex, age, marital status, education, employment status, number of residents in household, year of enrollment (dichotomized into before vs after 2017 to reflect the time of PEPFAR program wide scale-up of isoniazid preventive therapy), and clinical site. HIV-specific variables included antiretroviral therapy (ART) use (yes, no) and regimen abstracted from medical records, self-reported ART adherence in the past month (no missed ART doses, missed $\ge$ 1 doses), duration on ART, length of time in HIV clinical care, length of time since HIV diagnosis, CD4 count (<200 cells/mm³, $\ge$ 200 cells/mm³), VL (on ART for less than 6 months, on ART for 6 or more months and VL <1000 copies/mL and on ART for 6 or more months and VL ≥1000 copies/mL), TB diagnosis method (bacteriological, clinical), hyperglycemia, and body mass index (BMI). Additional variables included in the analysis were substance use and incarceration status. Definitions and categorizations of analytic variables not specified here have been previously described and summarized in Table S1, Supplemental Digital Content, http://links.lww.com/QAI/C13.^{13 (link)}Active TB was defined as meeting one of the following criteria: (1) bacteriologically confirmed through smear microscopy, culture, or WHO-approved rapid diagnostics (including GeneXpert MTB/RIF), (2) clinically indicated and having initiated combination therapy for active TB in the absence of bacteriological confirmation, or (3) identified by medical record abstraction within 3 months of enrollment. Participants were considered to be on combination therapy for active TB at enrollment if they were receiving (1) rifampicin (RIF), isoniazid (INH), ethambutol, and pyrazinamide or (2) INH and RIF for the final 4 months of treatment for active TB. Participants solely prescribed INH-based TB regimens were considered to be on preventative therapy.
We determined TB prevalence at entry or within 3 months of enrollment into AFRICOS, counting (1) previous diagnoses (those receiving continued combination TB therapy); (2) diagnoses made because of initial testing on entry into the cohort and within 3 months of enrollment; and (3) diagnosis based on WHO or ICD-10 codes in medical records at entry or within 3 months of enrollment.