Efficacy and safety of thrice weekly DOTS in tuberculosis patients with and without HIV co-infection: an observational study

BACKGROUND: Despite the latest World Health Organization guidelines advocating daily therapy in HIV-TB co-infected individuals, there are few recent studies comparing outcomes of thrice-weekly anti-tuberculosis treatment in HIV-positive and HIV-negative patients with TB. The present study sets out to compare TB treatment outcomes in these two groups in the Indian national programme, which currently involves thrice-weekly therapy for all, regardless of HIV status. METHODS: HIV-positive and HIV-negative were consecutively screened for enrolment into this prospective observational study, carried out at the All India Institute of Medical Sciences hospital, New Delhi, India, between 2006 and 2010. Patients were given short-course thrice-weekly rifampicin-based therapy, with all HIV-positive patients being started on highly active antiretroviral therapy at least 14 days after commencing TB treatment. Patients were regularly followed-up for 24 months after completion of treatment. RESULTS: 150 HIV-positive, 155 HIV-negative patients were enrolled consecutively for the study. Significantly higher treatment success (93.5% vs. 76.7% at end of treatment, p < 0.001) and lower mortality (2.8% vs. 21.6% on follow up, p < 0.001) were observed in HIV-negative patients. No significant difference was found in treatment failure (p = 0.16), sputum smear (p = 0.58) and culture conversion (p = 0.55), and non-serious adverse event incidence (p = 0.851) between the two groups. Low baseline CD4 cell count (<100 cells/ mm(3)) was the only predictor of mortality in HIV-TB patients (odds ratio 8 · 43, p = 0 · 013). CONCLUSIONS: Thrice-weekly anti-tuberculosis therapy is more effective in HIV-negative than in HIV-positive patients. However, outcomes in this HIV co-infected cohort were found to be similar to those reported previously with daily therapy, with no safety concerns. This should prompt further study into whether intermittent or daily therapy should be used universally in resource-poor settings, using large well executed randomised controlled trials. TRIAL REGISTRATION: NCT No. 00698334