Factors associated with death among HIV-uninfected TB patients in Thailand, 2004-2006

In countries with both TB and human immunodeficiency virus (HIV) epidemics, HIV is known to be the most powerful risk factor for death during tuberculosis (TB) treatment. Few recent studies have evaluated risk factors for death among HIV-uninfected TB patients in these countries. We analysed data from a multi-province demonstration project in Thailand to answer this question.

We prospectively collected data from HIV-uninfected TB patients treated for TB in four provinces and the national infectious diseases hospital in Thailand from 2004-2006. Standard WHO definitions were used to classify treatment outcomes. We used log-binomial multivariate regression to calculate adjusted relative risk (aRR) and 95% confidence intervals (CI) for factors associated with death.

Of 5318 cases, 441 (8%) died during TB treatment. The mean age was 47 years (range 8 months-97 years). Multidrug-resistant (MDR)-TB was diagnosed in 62 (1%). In multivariate analysis, patients older than 44 years were significantly more likely to die than patients aged 15-44 years [age 45-64, aRR 2.9 (CI 2.2-3.8)] [age > 64 years, aRR 5.0 (CI 3.9-6.6)]. Other independent risk factors for death included Thai nationality [aRR 3.9 (CI 1.6-9.5)], MDR-TB [aRR 2.8 (CI 1.7-4.8)], not being married [aRR 1.4 (CI 1.2-1.7)], and living in Chiang Rai province [aRR 2.7 (CI 1.7-4.4)].

The death rate was high among HIV-uninfected TB patients in Thailand. Efforts to improve TB diagnosis and treatment in the elderly and to improve MDR-TB treatment may help reduce mortality.