Mortality outcomes in early versus late onset colorectal cancer: A US National Inpatient Sample (NIS) analysis (2020).

e15651 Background: Colorectal Cancer (CRC) is the third most common cancer diagnosed in the United States and contributes to significant cancer-related morbidity and mortality. An upward trend in the incidence is noticed in the population below 50 years of age. For similar reasons, U.S. Preventive Services Task Force recommended screening at the age of 45 in 2021.For the sake of this study, we categorized early onset (EO) for age 45 and below, and late onset (LO) for above 45 years per new screening criteria. We compared socioeconomic characteristics, mortality, length of stay and hospital cost between EO and LO CRC. Methods: It is a retrospective cohort study of adult patients hospitalized in 2020 with Colorectal cancer in acute care hospitals across the USA. Patients were selected from the Nationwide Inpatient Sample (NIS) database. IRB approval was not obtained as de-identified data was utilized. Our study population included all patients with a discharge diagnosis of colorectal cancer as their primary diagnosis using the International Classification of the Diseases (ICD-10). The primary outcome was in-hospital mortality, secondary outcomes were length of hospital stay and total hospitalization charges. Analysis was performed using STATA version 18.0. Univariable and Multivariable logistic regression analysis were used to adjust for potential confounders. Results: There were 32 million discharges included in the NIS database in 2020, our study included 153809 with colorectal cancer which includes 12043 in EO and 141750 in LO CRC. Both population groups are mostly similar in terms of baseline characteristics, however EO group were more likely to have Hispanic population (18.7% vs 9.5%), history of inflammatory bowel disease (2.9% vs 1.2%), family history of CRC (6.4% vs 3.8%) and smoker (15.8% vs 12.8%). Multivariable analysis revealed that Age, Sex, Charlson Comorbidity Index, Family history, Smoking, and Median household income for patients were predictors of mortality. There was no statistically significant difference found in the adjusted mortality between the two groups (odds ratio 1.08, 95% CI 0.84-1.39). Lower length of stay was noticed in the EO group (odds ratio 0.48, 95% CI 0.07-0.89). Total deaths are lower in EO than LO group (0.04% vs 0.06%). Conclusions: There is no difference in mortality in early and late onset CRC in our study. However, EO CRC is associated with shorter length of stay in hospital. EO CRC disproportionately affects non-White patients, particularly Hispanic patients. Table: see text