Effect of preoperative psychiatric morbidity on postoperative outcomes of lung cancer surgery: A nationwide cohort study in South Korea

Objective: Lung cancer is the leading cause of cancer-related mortality worldwide, and cancer is associated with severe psychological distress. We aimed to investigate whether preoperative psychiatric morbidities affect clinical outcomes of lung cancer surgery in South Korea. Methods: Using the National Health Insurance Service database, all adult patients who were diagnosed with lung cancer and underwent lung cancer surgery from January 1, 2011, to December 31, 2018, were included in this retrospective, population-based cohort study. Depression, anxiety disorder, schizophrenia, alcohol abuse, non-alcohol substance abuse, and post-traumatic stress disorder were considered as preoperative psychiatric morbidities. Results: Overall, 60,031 adult patients who underwent lung cancer surgery were included in the final analysis. Of these, 17,255 (28.7%) patients had preoperative psychiatric morbidity before lung cancer surgery. Multivariable logistic regression modeling revealed patients with preoperative alcohol abuse (odds ratio [OR]: 2.51, 95% confidence interval [CI]: 1.24, 5.08; P = 0.011) and those with bipolar disorder (OR: 2.91, 95% CI: 1.94, 4.53; P < 0.001) to be associated with increased in-hospital mortality. Moreover, patients with preoperative psychiatric morbidities were associated with longer length of hospitalization (LOS), higher cost of hospitalization, and increased 1-year all-cause mortality. Conclusion: In South Korea, patients with preoperative alcohol abuse and bipolar disorder were associated with increased in-hospital mortality after lung cancer surgery. Moreover, they were associated with increased 1-year all-cause mortality, longer LOS, and higher total costs for lung cancer surgery.