Psychiatric Disorders Linked to Higher CRC Risk but Not Mortality

Patients with psychiatric disorders were associated with an elevated hazard of colorectal cancer (CRC), underscoring the need for increased monitoring and early intervention, according to a study published in Scientific Reports.1

Patients with psychiatric disorders had higher CRC risk but no increase in CRC-specific mortality. | Image Credit: Olivier Le Moal - stock.adobe.com

More Robust Evidence Needed on the Association Between Psychiatric Disorders and CRC

CRC is the third most common cancer worldwide, with more than 1.8 million new cases reported annually.2 Given this substantial disease burden, the researchers emphasized the importance of identifying associated risk factors to help reduce CRC incidence and associated health care burden.1

Psychiatric disorders such as anxiety and depression are connected with a range of chronic health conditions, including cancer.3 Potential causative links are psychological stress and poor health behaviors, which may drive neuroendocrine, immunological, and behavioral changes that increase cancer risk and promote its development.4

The researchers, however, highlighted the inconsistent findings of previous studies on psychiatric disorders and CRC incidence, with most stunted by moderate sample sizes or gender-limited cohorts.1 Consequently, they noted that more detailed, accurate information is needed to inform both clinical and psychological interventions better. To close this knowledge gap, the researchers used data from the UK Biobank to investigate whether psychiatric disorders increased patients’ risk of CRC incidence and mortality.

They created an exposed cohort of all eligible participants in the database who received their first diagnosis of a psychiatric disorder between July 2006 and December 2021. Then, the researchers matched each patient by gender and birth year with 10 comparators from the UK Biobank; matched individuals were alive and had no history of psychiatric disorders or cancer at the diagnosis date of the index patient’s psychiatric disorder. They used the Cox proportional hazards model to estimate the HRs of CRC risk after patients received a psychiatric disorder diagnosis.

Psychiatric Disorders Linked to Increased CRC Incidence, Not CRC-Specific Mortality

Among the 502,416 UK Biobank participants, 29,769 met the study’s eligibility criteria, 46.2% of whom were male, with a median age of 62 (IQR, 14) at first psychiatric diagnosis. After matching, the reference group comprised 297,690 individuals. Compared with the matched individuals, patients with psychiatric disorders were more likely to smoke, have higher body mass indexes, report a family history of CRC, and have lower socioeconomic and educational statuses.

During a median follow-up time of 5.69 years (IQR, 5.43), 190 CRC cases occurred among the exposed patients vs 921 in the unexposed cohort. The 15-year cumulative hazard of CRC was 0.64% (95% CI, 0.55%-0.74%) among patients with psychiatric disorders vs 0.31% (95% CI, 0.29%-0.33%) in the matched group (P < .0001).

CRC incidence rates were particularly higher among exposed patients diagnosed at older ages (1.67 per 1000 person-years and 0.58 per 1000 person-years for subjects aged ≥ 60 and < 60 years, respectively), among males (1.51 per 1000 person-years and 0.82 per 1000 person-years for males and females, respectively), and among smokers (1.35 per 1000 person-years and 0.71 per 1000 person-years for ever smokers and never smokers, respectively).

Regarding CRC-specific mortality, 47 related deaths occurred in individuals with psychiatric disorders vs 246 in the reference group, representing CRC death rates of 64.38 and 71.51 per 1000 person-years, respectively. As a result, the 15-year cumulative hazard of CRC death was 24.74% (95% CI, 18.78%-31.50%) in patients with psychiatric disorders vs 26.71% (95% CI, 23.88%-29.70%) in the matched cohort.

After controlling for confounders in the sex-combined multivariable models, the researchers found an increased CRC risk among patients with psychiatric disorders compared with matched unexposed individuals (adjusted HR [aHR], 1.93; 95% CI, 1.64-2.27). Specifically, the aHRs were 2.51 (95% CI, 1.04-6.06) for psychotic disorders, 2.11 (95% CI, 1.73-2.58) for substance abuse, 1.85 (95% CI, 1.40-2.44) for anxiety, and 1.74 (95% CI, 1.36-2.24) for depression. In addition, patients with numerous psychiatric disorders had higher aHRs for CRC incidence than those with a single disorder (2.53 [95% CI, 1.9-3.37] vs 1.78 [95% CI, 1.48-2.13]).

In contrast, no elevated hazard of CRC-specific mortality was observed among patients with vs without psychiatric disorders (aHR, 0.88; 95% CI, 0.64-1.22; P = .46). Similarly, no significantly elevated CRC-specific mortality risk was seen by psychiatric disorder type.

Clinical Implications and Opportunities for Targeted CRC Prevention

The authors acknowledged several limitations, including that the UK Biobank primarily consists of White participants and has an older age distribution. Because of this, the study may not accurately represent the general population. Additionally, the national cancer registries from which CRC cases were identified may be subject to misclassification or underreporting. Nonetheless, they expressed confidence in their findings and used them to suggest future treatment strategies.

“…the rising incidence of CRC diagnoses indicates a potential need for targeted health services,” the authors concluded. “This could involve integrating this population into existing CRC screening programs, such as fecal immunochemical testing and colonoscopy surveillance, to facilitate earlier detection and intervention.”

References

1. Wang Z, Zhu T, Huang L, et al. Psychiatric disorders associated with increased risk of colorectal cancer in the UK Biobank cohort. Sci Rep. 2026;16(1):1597. doi:10.1038/s41598-025-31083-1
2. Rawla P, Sunkara T, Barsouk A. Epidemiology of colorectal cancer: incidence, mortality, survival, and risk factors. Prz Gastroenterol. 2019;14(2):89-103. doi:10.5114/pg.2018.81072
3. Moussavi S, Chatterji S, Verdes E, Tandon A, Patel V, Ustun B. Depression, chronic diseases, and decrements in health: results from the World Health Surveys. Lancet. 2007;370(9590):851-858. doi:10.1016/S0140-6736(07)61415-9
4. Lutgendorf SK, Sood AK. Biobehavioral factors and cancer progression: physiological pathways and mechanisms. Psychosom Med. 2011;73(9):724-730. doi:10.1097/PSY.0b013e318235be76