Colorectal Cancer and the Risk of Mortality Among Individuals with Suicidal Ideation

Suicide is a major public health problem that has grown at alarming rates in the last two decades. Colorectal cancer (CRC) is one of the most common causes of cancer deaths in the United States in both males and females. However, the influence of suicidal ideation (SI) on the association between CRC and risk of mortality has not been well examined. Methods: For this study, the 2005–2018 National Health and Nutrition Examination Survey (NHANES), a nationally representative survey of United States adults aged 20 years or older, was utilized. CRC survivorship was determined from self-reported data on CRC, and mortality was ascertained by linking the NHANES data with death files from the National Death Index up to December 2019. Suicidal ideation (SI) confirmation was based on a response to a survey question. Results: People with SI had a significantly higher rate (12.3% vs. 7.5%, p < 0.01) of mortality than those without SI. Also, individuals with CRC (2.4%) had a statistically significant higher rate of frequent SI (almost daily) than individuals without CRC (0.6%). Upon a mean follow-up of 7.5 years, more CRC survivors (34.6%) died than non-CRC survivors (7.6%). The adjusted HR was elevated HR = 5.4 among individuals who had CRC and SI but close to 1.0 among individuals who had a history of CRC alone after adjusting for demographic and health variables. Conclusions: In this first national study in the U.S., we found that SI and CRC combined had worse mortality outcomes than CRC alone. Additionally, people with CRC were more likely to experience frequent SI. Our findings underscore the importance of mental healthcare and psychological well-being promotion among individuals with chronic diseases and the high need for integrated care approaches that address both physical and mental health needs.