Depression and risk of tuberculosis: a nationwide population based cohort study

BACKGROUND: Studies on the association between depression and risk of tuberculosis (TB) are lacking. OBJECTIVE: To determine the association between depression and risk of TB. METHODS: From a nationwide database, patients with depression were identified to form the exposure cohort between 2003 and 2013. The control cohort comprised an equivalent number of subjects without any mood disorders, with each subject age-and sex-matched to a patient in the exposure cohort. The incidence of TB was identified in the exposure cohort and control cohort between 2003 and 2013. A multivariable Cox proportional hazards model was used to estimate the association between depression and the subsequent risk of TB. RESULTS: A total of 32 372 patients with depression and the same number of controls were identified. The risk of TB in the depression cohort was 2.63-fold (95%CI 1.74-3.96) higher than in the control cohort. When the depression was classified as 'mild' and 'severe', the risk of TB was proportional to depression severity. CONCLUSIONS: Patients with depression are at a higher risk for TB, and a dose-response relationship exists between depression and the subsequent risk of TB.