Factors of loss to follow-up during tuberculosis treatment in a low-incidence region

Objective The proportion of successfully treated tuberculosis (TB) patients remains below the WHO target in France, because of a high proportion of loss to follow-up. We aimed to identify factors associated with loss to follow-up in northern France, a low-incidence area. Methods Between 1997 and 2017, all consecutive patients diagnosed with TB at the Tourcoing Hospital, except those infected with multidrug-resistant or extensively drug-resistant strains, were included in a retrospective cohort study. A logistic regression analysis was performed to determine factors associated with loss to follow-up. Results One hundred and ninety patients were included. Previous TB treatment was reported in 32 patients (17%), extrapulmonary TB in 107 (56%), and HIV infection in 44 (23%). The proportion of loss to follow-up was 15%. In multivariate analysis, the risk of loss to follow-up decreased in case of first TB treatment (OR 0.36; 95% CI: 0.14-0.92, P=0.03) and increased in non-HIV-infected patients (OR 7.67; 95% CI: 1.00-59.0, p=0.05). Support for compliance was more frequent in HIV-infected patients (23% vs. 7%, p=0.005). Conclusion The proportion of loss to follow-up was high. HIV infection was associated with a lower risk of loss to follow-up, likely to be due to more frequent support for compliance.