EP373 - Independent and Cumulative Association of Psychosocial Risks with Colectomy Outcomes in United States Veterans

Purpose/Background: Social isolation, suicide risk, mental health disorders, substance abuse, food insecurity, and housing instability (psychosocial risks) are emerging as important determinants of health outcomes. This study evaluates the prevalence of perioperative psychosocial risks and their association with complications independent of conventional risks after elective colectomy in a national U.S. Veterans cohort.

Methods/Interventions: We conducted a retrospective cohort study of adult patients in the United States who underwent elective colectomy within the Veterans Health Administration (VHA) system between 2009 and 2024. Demographic and comorbidity data were captured using the Veterans Affairs Surgical Quality Improvement Program (VASQIP). High-risk medical comorbidities were defined in similar fashion to the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP). Structured electronic medical record data from the VHA Corporate Data Warehouse were used to generate a composite psychosocial risk score within 90 days of surgery by summing risks across six domains: social isolation, suicide risk, mental health disorders, substance abuse, food insecurity, and housing instability. The primary outcome was any 30-day VASQIP-defined post-operative complication. Multivariable logistic regression models were used to estimate the odds of complication as a function of psychosocial risk.

Results/Outcomes: A total of 31,971 patients who underwent elective colectomies were included [partial colectomy: n=30,895 (97%), total colectomy: n=1,076 (3%), open approach: n=17,484 (55%), minimally invasive approach: n=14,487 (45%)]. The most common surgical indication was malignancy (n=16,743, 52%). Non-malignant indications (n=15,228, 48%) included diverticular disease (n=4,244, 28%), inflammatory bowel disease (n=804, 5%), and other conditions (n=10,180, 67%). Overall, 7,654 (24%) patients had ≥2 psychosocial risks, 1,718 (5%) were female, 9,768 (30%) were non-white, 15,521 (48%) had ≥1 high-risk medical comorbidity, and 5,512 (21%) experienced ≥1 post-operative complication. Veterans with ≥2 psychosocial risks had longer post-operative hospital stays (9.6 vs. 7.1 days, p< 0.001) and were more likely to return to the operating room within 30 days (10% vs. 6.4%, p< 0.001) compared to those with < 2 psychosocial risks. On multivariable logistic regression, psychosocial risk demonstrated a strong and graded exposure-response relationship with post-operative complications. A single psychosocial risk was associated with significantly higher odds of a complication (OR 1.50, 95% CI 1.39-1.61, p< 0.001; Table 1), and the odds increased incrementally with additional psychosocial risks. Veterans with 5 or 6 psychosocial risks experienced the greatest vulnerability, with more than a fourfold increase in odds of a complication (OR 4.57, 95% CI 2.17-9.62, p< 0.001; Table 1).

Conclusion/Discussion: Psychosocial risk is common among Veterans undergoing elective colectomy and is strongly associated with an increased odds of post-operative complications in a exposure-response manner. This strong, linear relationship of patient-level psychosocial risk burden and post-operative complications has been posited but not previously observed. These findings emphasize the need for systematic psychosocial risk assessment and potentially targeted perioperative interventions to improve surgical outcomes in vulnerable populations.

Multivariable logistic regression of post-operative complications among Veterans undergoing elective colectomy within the Veterans Health Administration between 2009 and 2024 (n=31,971).
Abbreviations: OR, odds ratio; CI, confidence interval; ASA classification, American Society of Anesthesiologists Physical Status Classification System.