Risk of Lung Cancer and Risk Factors of Lung Cancer in People Infected with Tuberculosis

This study investigated lung cancer risk in people infected with tuberculosis (TB) compared to the general population and evaluated factors associated with lung cancer in TB-infected individuals. Mandatory reported TB infection case data in Gyeonggi Province, South Korea (2010 to 2016) were obtained and linked with medical usage and health screening data from the National Health Information Database. Lung cancer incidence in patients with TB was compared to that in the general population using standardized incidence ratio (SIR), adjusted for age and sex. Lung cancer risk factors in patients with TB were studied using the Cox proportional hazards model. By April 2022, 1.26% (n = 444) of 35,140 patients developed lung cancer after TB diagnosis. Compared to the incidence in the general population, increased lung cancer risk in people with TB was observed (SIR: 2.04, 95% CI: 1.85-2.23). Multivariate analysis showed increased lung cancer in TB-infected individuals, associated with being male (hazard ratio [HR]: 2.24, 95% CI: 1.65-3.04), 1-year increase of age (HR: 1.09, 95% CI: 1.08-1.10), ever smoking (HR: 1.42, 95% CI: 1.02-1.97), and amount of daily smoking with one pack or more (HR: 2.17, 95% CI: 1.63-2.89). Increased lung cancer risk was noted in patients with TB compared to the general population, and sex, age, and smoking were factors associated with lung cancer in patients with TB.