Social and structural determinants of blood transfusion in hospitalized patients with colorectal cancer and lower gastrointestinal bleeding.

208 Background: Lower gastrointestinal bleeding (LGIB) is a common and potentially life-threatening complication in patients with colorectal cancer (CRC). Blood transfusions are frequently required in this setting, but disparities in their utilization based on sociodemographic and hospital-related factors remain underexplored. This study aims to evaluate disparities in blood transfusion utilization among adult patients hospitalized with LGIB and a concurrent diagnosis of CRC in the United States. Methods: We conducted a retrospective analysis using the National Inpatient Sample (NIS) database from 2016 to 2020. Adult patients hospitalized with a primary diagnosis of LGIB and a concurrent diagnosis of CRC were identified using ICD-10 codes. The primary outcome was the receipt of blood transfusion. Baseline characteristics were compared using t-tests and chi-square tests. Multivariable logistic regression was used to assess the odds of receiving a transfusion, adjusting for age, sex, race, Charlson Comorbidity Index, insurance type, hospital region, hospital location and teaching status, and median household income by ZIP code. A two-tailed p-value < 0.05 was considered statistically significant. Results: Among 450,305 patients hospitalized with LGIB and CRC, 59,700 (13.3%) received a blood transfusion. Transfused patients were older (mean age 71.2 vs. 67.2 years, p < 0.001) and more likely to be female (52.6% vs. 47.3%, p < 0.001). Each one-year increase in age was associated with a 2.4% increase in the odds of transfusion (adjusted OR [aOR] 1.024; p < 0.001). Compared to White patients, African American (aOR 1.76), Hispanic (aOR 1.38), and Asian (aOR 1.42) patients had higher odds of receiving transfusions (all p < 0.001). Patients in teaching hospitals had 20.9% lower odds of transfusion compared to non-teaching hospitals (aOR 0.79; p < 0.001). Patients treated in urban hospitals had 12% lower odds compared to those in rural settings (aOR 0.88; p = 0.009). Regional differences were noted, with patients in the Midwest (aOR 0.57), South (aOR 0.81), and West (aOR 0.78) having lower odds compared to those in the Northeast (all p < 0.001). Compared to those with private insurance, patients with Medicare (aOR 1.23), Medicaid (aOR 1.75), and self-pay status (aOR 1.73) were more likely to receive transfusions (all p < 0.001). Conclusions: Significant disparities exist in blood transfusion practices among hospitalized patients with colorectal cancer and lower gastrointestinal bleeding. Older age, racial and ethnic minority status, public or no insurance, and treatment at non-teaching, rural, or non-Northeastern hospitals were associated with increased odds of transfusion. These findings call for more equitable, evidence-based transfusion strategies and targeted interventions to eliminate systemic differences in supportive cancer care.