Risk factors for feelings of sadness and suicide attempts among cancer survivors in South Korea: findings from nationwide cross-sectional study (KNHANES IV-VI)

Introduction As the number of cancer survivors is rapidly increasing with the increased incidence of the disease and improved survival of patients, the prevalence of, and risk factors for, mental health problems and suicidality among cancer survivors should be examined. Methods and analysis Using data obtained from the Korean National Health and Nutrition Examination Survey (2007-2013), we examined 1285 and 33 772 participants who had been and never been diagnosed with cancer, respectively. We investigated the risks of feelings of sadness and suicide attempts among cancer survivors and general population and examined differences in the risks of cancer survivors among subgroups according to cancer-related characteristics. Results The median age of survivors at the time of the survey and at diagnosis was 63 and 54 years, respectively. After adjusting for sex, level of education, household income, occupation, marital status, cancer type, current status of treatment, age at diagnosis and years since diagnosis, the risk of suicide attempts was significantly higher in participants diagnosed with cancer before 45 years of age compared with those diagnosed at 45-64 years (adjusted OR=3.81, 95% CI 1.07 to 13.60, P=0.039), and the higher risk of suicide attempts with borderline significance was found in those for whom more than 10 years had passed since diagnosis compared with those for whom the diagnosis was made only 2-10 years ago (adjusted OR=3.38, 95% CI 0.98 to 11.70, P=0.055). However, feelings of sadness were not significantly associated with any cancer-related characteristic. Conclusion Our results reveal an increased risk of suicide attempts among cancer survivors diagnosed early in life and in those for whom more than 10 years has passed since the diagnosis, suggesting the need for intensive monitoring and support for mental health problems and suicidal risks in this population.