To the Editor: We commend Kisley and colleagues1 for highlighting the low uptake of colorectal cancer screening in individuals with a severe mental illness. In Canada, our Cancer and Severe Mental Illness Project (CaSMIP) collaborations2,3 have made similar observations and identified several challenges, which may explain the findings. In our experience, health system, psychopathology and social determinants of health can influence screening uptake shared in some of our observations below.
First, the receipt of the mailed faecal immunochemical test (FIT) packages can be affected by the stability of housing as well as access to mail. Homeless individuals, those with insecure housing and the unsupported are particularly vulnerable.
Second, illness‐related factors such as distraction, inattention or cognitive deficits can impair ability to follow the written or visual instructions on the FIT without assistance. The presence of addictions, positive symptoms of psychosis such as hallucinations, agitation or paranoid delusional beliefs in combination with negative symptoms such as amotivation or lack of volition can compromise test completion.4
Third, access to a toilet and mechanical aspects of obtaining a faecal sample, storing or returning the FIT kit can be challenging for some individuals.
Fourth, regarding colonoscopies, bowel preparation is critical to this procedure. We have observed significant difficulties associated with unassisted bowel preparation for some individuals. In our experience, several hours of bowel preparation can be distressing, confusing or even incorporated into paranoid beliefs, such as being poisoned. In addition, regular, reliable ease of access to toilet facilities is important, and fasting regimes may be difficult to adhere to.4
Inadequate or unsuccessful bowel preparation often leads to suspended colonoscopies. In our experience, several individuals who are paranoid, severely anxious or living with trauma find the concept of a rectally inserted tube with a light and camera distressing and may decline consent at any stage of the process. They may benefit from further psychiatric support.4
Considering these real‐world issues in supporting individuals with severe mental illness, we have developed a person‐centred collaborative psychiatric case management and oncology navigation model that supports both FIT and colonoscopy screening, providing advocacy when required (unpublished data).
- 1. Kisely S, Seth R, Jordan SJ, et al. Participation in the National Bowel Cancer Screening Program by people with severe mental illness, Australia, 2006–2019: a national data linkage study. Med J Aust 2024; 221: 617‐622.
- 2. Faculty of Health Sciences, Queen's University. Navigating the complexities of cancer and severe mental illness. Kingston, Queen's University, 2023. https://healthsci.queensu.ca/stories/feature/navigating‐complexities‐cancer‐and‐severe‐mental‐illness (viewed Mar 2025).
- 3. Gorodensky JH, Davis L, Griffiths R, et al. Inequities in the time to colon cancer diagnosis among individuals with severe psychiatric illness. Cancer Med 2025; 14: e70623.
- 4. Queen's Health Sciences. Dr Oyedeji Ayonrinde — don’t leave me behind: navigating cancer and psychosis, 5 à 7 research talks [video]. https://youtu.be/oShiVMtvI40?si=IVnr57FSpdKyNmIT (viewed Mar 2025).


No relevant disclosures.
Author contributions:
Ayonrinde O: Conceptualization (lead); writing – original draft (lead) review and editing (equal). Mohamed S: Review and editing (equal). Nensi J: Review and editing (equal).