Psychiatric Disorders and Risk of Colorectal Cancer: A UK Biobank Cohort Analysis

Background: Psychiatric disorders are associated with a number of chronic health conditions, including cancer. However, data on the association between multiple types of psychiatric disorders and colorectal cancer (CRC) are scarce. The aim of the present study was to determine whether there is an association between psychiatric disorders and subsequent CRC using UK Biobank.Methods We excluded participants who had previous cancer diagnosis (except non-melanoma skin cancer) prior to baseline, and conducted a matched cohort study with new-onset psychiatric disorder patients after recruitment as the exposure group and matched individuals from the general population as the reference group. Through UK Biobank, we obtained clinical diagnoses for the psychiatric-disorder patients from their hospital records. The Cox model was used to estimate the hazard ratios (HRs) with 95% confidence intervals (CIs) of CRC risk after diagnosis of a psychiatric disorder, controlling for multiple risk factors.Findings: We identified 29,769 individuals with psychiatric disorders. During follow-up (median duration of 5.69 [IQR: 5.43] years), 190 cases of CRC were identified in the psychiatric patients (1.13 per 1000 person-years), compared with 921 cases in the reference individuals (0.53 per 1000 person-years). Individuals with clinically confirmed psychiatric disorders were at increased risk of CRC (HR, 1.93 [95% CI, 1.64–2.27]). The association with psychiatric disorders is more pronounced for colon cancer (HR, 2.15 [95% CI, 1.77–2.60]), particularly men (HR, 2.06 [95% CI, 1.67–2.53]). The risk of CRC in psychiatric patients is higher for individuals with multiple pre-pandemic psychiatric disorders (HR 2.53 [95% CI, 1.90–3.37]).Interpretation: Our findings suggest that patients with psychiatric disorders, particularly men, are at increased risk of CRC, specifically colon cancer. These findings highlight the need for measures to decrease the risk of CRC in individuals with psychiatric disorders, such as monitoring and early intervention.Funding Information: This work was supported by the National Natural Science Foundation of China (grant numbers: 82173253, 82103539), Sichuan Science and Technology Program (grant numbers: 2021YFH0005, 2022YFH0003).Declaration of Interests: All others authors declare no competing interests.Ethics Approval Statement: The UK 139 Biobank has full ethical approval from the NHS National Research Ethics Service (16/NW/0274).