S0313 Psychiatric Diagnosis May Result in a Higher Incidence of Colorectal Cancer in Patients with a Positive Fecal Immunochemical Test in a Veteran Patient Population

INTRODUCTION: The fecal immunochemical test (FIT) is used widely as a screening method for colorectal cancer (CRC). Limited data is available on colonoscopy compliance or outcomes in psychiatric patients. In addition, the impact of a positive FIT in this population has not been assessed to date. The primary aim of our study was to determine colonoscopy outcomes of patients with psychiatric illness who were noted to have a positive FIT within a large, heterogenous veteran population. METHODS: The VA Loma Linda Healthcare System electronic medical record was queried for all patients having FIT between October 1, 2014 and September 30, 2015. Inclusion criteria were positive FIT and the presence of a psychiatric diagnosis. Data collected included demographic information, FIT result, endoscopist performing colonoscopy, type, and quality of preparation, withdrawal time, Endocuff use, adenoma size and location along with the presence of psychiatric diagnosis. Primary outcome measures were adenoma detection rate (ADR), advanced adenoma detection rate (AADR), sessile serrated adenoma/polyps (SSA/P), CRC, preparation quality and duration to colonoscopy. Statistical analysis was performed with R software with Mann-Whitney test, chi-square, Fisher’s exact test, logistic regression and linear regression analysis as indicated. RESULTS: During the study period, 7778 FIT tests were distributed. Of those distributed, 638 patients (8%) were positive and met study criteria. 380 (59.5%) underwent diagnostic colonoscopy. The average age was 66 years old. Psychiatric illness was present in 204 patients (67.6%) undergoing colonoscopy. The prevalence of ADR, AADR, SSA/P, ASSA/P and CRC was 64.4%, 25%, 13.95%, 2.6% and 3.42% respectively. Patients with a psychiatric illness were observed to have a higher rate of colonoscopy follow-up (OR = 1.89, P = 0.04) as well as a higher incidence rate of CRC, (OR = 5.21, P = 0.01). There was no significant difference in any other parameter compared to veterans without psychiatric illness. CONCLUSION: Contrary to previous studies, patients diagnosed with a psychiatric illness and were noted to have a positive FIT were observed to have higher adherence to colonoscopy as well as higher CRC incidence. Increased adherence to colonoscopy may be secondary to a systematic approach remind these patients about their clinical appointments. Larger, prospective studies will need to be performed to determine why this conflict in observations exists among psychiatric patients.Table 1