Temporal Trends in Mental Disorder Rates among Patients with Colorectal Cancer: A Comprehensive Analysis

Background: Colorectal cancer (CRC) stands as one of the most prevalent and burdensome malignancies worldwide. Similar to other cancers, CRC has been associated with the development of psychiatric diseases, including anxiety and depression. However, temporal trends in psychiatric disorders rates within CRC patients have not been investigated so far. Methods: The present study included 15,619 individuals with colorectal cancer and 78,095 propensity score-matched individuals without cancer, who were identified within the Disease Analyzer (IQVIA) database in Germany between 2005 and 2022. Cox regression analysis was conducted to assess the association between CHC and subsequent psychiatric diseases, including depression, anxiety disorders, and adjustment disorder, by period (2005-2010, 2011-2016, 2017-2022). Results: The 12-month cumulative incidence of any psychiatric disorder diagnosis in the CRC cohort increased from 6.3% in 2005-2010 to 8.2% in 2017-2022. The strongest increase was observed for reaction to severe stress and adjustment disorder (1.0% in 2005-2010 to 2.6% in 2017-2022). Notably, the strong increase in psychiatric disorders was not specific for cancer patients since a slight increase in psychiatric disorders was also observed in the non-cancer cohort. Regression analyses revealed that CRC was strongly and significantly associated with an increased risk of depression, anxiety disorders, reaction to severe stress and adjustment disorders, as well as any psychiatric disorder. Of note, the extent of the association was stronger in 2017-2022 compared to 2005-2010, clearly proving a "real" increase in the rates of psychiatric disorders over time. Conclusions: This study presents novel data from a large cohort of outpatients in Germany, providing strong evidence for an increase in psychiatric disorders in the recent years. These findings contribute to the existing body of literature and should trigger the recognition of psychiatric problems in cancer survivors.