Survival rate and risk factors of mortality among HIV/tuberculosis-coinfected patients with and without antiretroviral therapy

Background: The impact of antiretroviral therapy (ART) on survival among patients coinfected with HIV and tuberculosis (TB) has not been well established. Methods: A retrospective cohort study was conducted among HIV-infected patients with TB between January 2000 and December 2004. Patients were categorized into ART+ group (received ART) and ART- group (did not receive ART) and were followed until April 2005. Results: A total of 1003 patients were identified; 411 in ART+ group and 592 in ART- group. Median (interquartile range) CD4 count was 53 (20-129) cells/mm(3). Survival rates at 1, 2, and 3 years after TB diagnosis were 96.1%, 94.0%, and 87.7% for ART+ group and 44.4%, 19.2%, and 9.3% for ART- group (log-rank test, P < 0.001). Cox proportional hazard model showed that ART was associated with lower mortality rate; gastrointestinal TB and multidrug resistant TB were associated with higher mortality rate (P < 0.05). Among patients in ART+ group, the patients who delayed ART >= 6 months after TB diagnosis had a higher mortality rate than those who initiated ART < 6 months after TB diagnosis (P 0.018, hazard ratio = 2.651, 95% confidence interval = 1.152-6.102). Conclusions: Antiretroviral therapy substantially reduces mortality rate among HIV/TB-coinfected patients. Initiation of ART within 6 months of TB diagnosis is associated with greater survival.