Treatment outcomes of multidrug-resistant tuberculosis patients in Zhejiang, China, 2009-2013

Abstract

Objectives: To examine treatment outcomes and factors associated with poor outcome of multidrug-resistant (MDR) tuberculosis (TB) in China.

Methods: We conducted a prospective observational cohort study including consecutive patients with MDR-TB between 2009 and 2013 in six regions of Zhejiang province. Patients were prescribed treatments by infectious disease specialists, and treatment outcomes were recorded. Sociodemographic characteristics were obtained through a structured questionnaire. The primary endpoint was poor treatment outcomes, defined as treatment failure based on microbiologic persistence, default (lost to follow-up) or death at 24 months. We assessed risk factors for poor treatment outcomes using a Cox proportional hazards model.

Results: A total of 820 MDR-TB patients were observed, and 537 with known treatment outcomes were included in our study. Overall, the treatment success rate was 40.2 per 100 years (374/537 participants, 69.6%), while treatment failure, death and default rates were 10.0 per 100 years (101 participants, 18.8%), 3.4 per 100 years (36 participants, 6.7%) and 2.7 per 100 years (26 participants, 4.8%) respectively. Independent predictors of poor treatment outcomes included age >60 years (hazard ratio (HR) 2.3, 95% confidence interval (CI) 1.2-4.2), patients registered as experiencing relapse (HR 2.2, 95% CI 1.1-4.4), patients registered as receiving treatment after failure (HR 2.4, 95% CI 1.2-4.9), use of standardized MDR-TB regimens (HR 0.6, 95% CI 0.4-1.0), cavitary disease (HR 4.9, 95% CI 2.8-8.6) and adverse events (HR 2.5, 95% CI 1.2-5.5).

Conclusions: Under well-designed treatment and management scheme, high treatment success rates were achieved in a high-MDR-TB-burden country. Antimicrobial susceptibility testing for all second-line drugs should be conducted to further assist in the treatment of MDR-TB.

Keywords: Drug-resistant tuberculosis; MDR-TB; Standardized treatment; Treatment outcomes; Tuberculosis.