Predictors of failure to complete tuberculosis treatment in London, 2003-2006

Setting: London, 2003-2006. Objectives: To investigate tuberculosis (TB) treatment completion failure in London and associated risk factors during 2003-2006. Design: Cross-sectional analysis of treatment outcome and other explanatory variables in a cohort of TB patients reported to the London TB Register from 2003 to 2006. Methods: An innovative definition of TB treatment outcome more suitable for low-incidence industrialised countries, such as the United Kingdom, was adopted. A multivariable logistic approach was used to assess predictors of unsuccessful outcome. Results: A total of 12,929 TB cases were notified from 2003 to 2006, of which 12% (n = 1536) failed to complete TB treatment. The proportion of cases failing to complete treatment showed a significant decrease from 2003 to 2006 (13% in 2003 vs. 10% in 2006). Males, the elderly, hospitalised patients, short- and long-term immigrants, Whites and the least deprived were more likely to fail to complete treatment. Conclusions: The proportion of TB treatment success in London exceeded the World Health Organization recommended threshold of 85%. Some specific categories of patients that are more likely to fail to complete treatment should be targeted by health services to enhance their engagement and adherence to the treatment regimen.