Abstract
BACKGROUND: Many individuals with tuberculosis (TB) experience various psychological problems after TB diagnosis, and they may also have suicidal ideations and suicidal attempts associated with TB-related depression or stigma. Until now, little is known about suicide rates among individuals with TB. We aimed to investigate the trends, characteristics, and contributing factors of suicide deaths among individuals with TB, using a Republic of Korea nationwide cohort. METHODS: This was a retrospective nationwide cohort study using data of the K-TB-N cohort. We analyzed 310,194 individuals with TB registered in the Korean National Tuberculosis Surveillance System between 2012 and 2021. Suicidal deaths were identified using the International Classification of Diseases 10th revision codes (X60-X84) from the Statistics Korea database. Participants were followed up until death, censoring, or December 2022. We calculated suicide incidence rates, examined temporal distribution of suicide occurrence following TB diagnosis using Poisson regression, and used multivariate Cox proportional hazards models, including age-stratified analyses, to identify factors associated with suicide. RESULTS: Altogether, 1314 (0.42%) died by suicide [1.6% of all deaths (1314/80,323)]. Men and individuals aged ≥ 60 years accounted for 76.9% and 56.1% of suicide deaths, respectively. Overall suicide incidence was 0.77/1000 person-years, more than twice as high in men compared to that in women (1.03 vs. 0.42/1000 person-years), and increased with age (from 0.32 in 20-29 years to 1.59 in ≥ 80 years/1000 person-years). Suicide incidence within one year after TB diagnosis was 2.04/1000 person-years. Notably, 31.3% of the suicides occurred during TB treatment. The incidence of suicide was highest immediately after TB diagnosis and tended to decrease over time. Male sex, older age, pulmonary TB, sputum smear positivity, comorbidities, and mental disorders were significantly associated with higher suicide risk. The risk factors for suicide showed different patterns across age groups (younger adults: pre-existing mental health conditions; middle-aged adults: low income and infectiousness; and older adults: comorbidities and disability). CONCLUSIONS: Suicide is a notable cause of death among individuals with TB in Republic of Korea, particularly early after diagnosis. The factors contributing to suicide risk differed depending on sex and age. Routine mental health screening and early targeted psychosocial intervention strategies should be integrated into national TB care programs to reduce preventable deaths.