Burden of tuberculosis in an antiretroviral treatment programme in sub-Saharan Africa: Impact on treatment outcomes and implications for tuberculosis control
Desmond Tutu HIV Centre, Institute for Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa; Infectious Diseases Epidemiology Unit, School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa; Clinical Research Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom; Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY, United States; Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Anzio Road, Observatory 7925, Cape Town, South Africa
OBJECTIVES: To determine burden and risk factors for tuberculosis (TB) in an antiretroviral treatment (ART) programme and its impact on ART outcomes. DESIGN: Prospective cohort study. METHODS: Prevalent TB was assessed at baseline and incident TB was ascertained prospectively over 3 years among 944 patients accessing a community-based ART programme in South Africa. RESULTS: At enrollment, median CD4 cell count was 96 cells/μl and 52% of patients had a previous history of TB. Prevalent TB (current antituberculosis treatment or active TB) was present in 25% and was strongly associated with advanced immunodeficiency. During 782 person-years of ART, 81 cases of TB were diagnosed. The incidence was 22.1/100 person-years during the first 3 months of ART and decreased to an average of 4.5/100 person-years during the second and third years. In multivariate analysis, risk of incident TB during follow-up was only associated with the current absolute CD4 cell count at that time point; an increase of 100 cells/μl was associated with a 25% lower risk (P = 0.007). Although prevalent and incident TB were associated with greater than two-fold increased mortality risk, they did not compromise immunological and virological outcomes among survivors at 48 weeks. CONCLUSIONS: Late initiation of ART was associated with a major burden of TB in this ART programme. TB reduced survival but did not impair immunovirological outcomes. Reductions in TB incidence during ART were dependent on CD4 cell count; however, after 3 years of treatment, rates were still 5- to 10-fold higher than among non-HIV-infected people. Earlier initiation of ART may reduce this burden of TB. © 2006 Lippincott Williams & Wilkins.
antiretrovirus agent; cotrimoxazole; dapsone; didanosine; efavirenz; isoniazid; lamivudine; lopinavir plus ritonavir; nevirapine; RNA directed DNA polymerase inhibitor; stavudine; tuberculostatic agent; zidovudine; adult; article; CD4 lymphocyte count; controlled study; disease association; female; follow up; highly active antiretroviral therapy; human; Human immunodeficiency virus infection; immunology; major clinical study; male; mortality; multivariate analysis; patient assessment; priority journal; South Africa; treatment outcome; tuberculosis; tuberculosis control; Adult; Africa South of the Sahara; Anti-Retroviral Agents; CD4 Lymphocyte Count; Cost of Illness; Female; HIV Infections; Humans; Incidence; Male; Prevalence; Prospective Studies; Recurrence; Risk Factors; Treatment Outcome; Tuberculosis; Viral Load