A national estimate of mental disorders and mortality outcomes in cancer survivors

Abstract

Background: This study evaluated the prevalence of various mental disorders and their influence on mortality outcomes in individuals with cancer. Methods: The authors' institutional database included patients with cancer diagnosed between 2011 and 2015 who had mental disorders and death information up to 2021. Mental disorders included nonaffective psychotic disorders, affective psychotic disorders, anxiety-related and stress-related disorders, alcohol or drug misuse, and mood disorders without psychotic symptoms. The causes of death were classified as all-cause, cancer-related, or suicide. Individual matching was performed to randomly match cancer survivors with and without mental disorders according to age at cancer diagnosis, year of cancer diagnosis, sex, and cancer site. The association between mental disorders and mortality risk was assessed using a Cox proportional hazards model and competing-risk analyses. Results: Among 637,491 cancer survivors (mean age, 58.9 years), there were 238,654 deaths from any cause and 2255 deaths from suicide. Incidence rates varied across disorders, with the highest rates observed for anxiety-related and stress-related disorders and mood disorders without psychotic symptoms. Mental disorders were associated with an increased risk of all-cause and cancer-related mortality. Adjusted hazard ratios (HRs) for nonaffective psychotic disorders, affective psychotic disorders, anxiety-related and stress-related disorders, alcohol and drug misuse, and mood disorders without psychotic symptoms were as follows: HR, 2.49 (95% confidence interval [CI], 2.22-2.80); HR, 2.38 (95% CI, 2.21-2.57); HR, 1.02 (95% CI, 1.01-1.04); HR, 2.13 (95% CI, 1.87-2.43); and HR, 1.27 (95% CI, 1.24-1.30), respectively, for all-cause mortality. Suicide risk was higher in patients who had mental disorders, especially within the first 6 months after diagnosis. Conclusions: The current findings underscore the impact of mental illness on mortality among cancer survivors in Korea, specifically highlighting the elevated rates of anxiety, stress, and mood disorders.