Disparities in Clinical Outcomes Between Younger and Older IBD Patients With Respect to Insurance Status: An Analysis of the National Inpatient Sample 2016-2020

Background: Usage of biological therapy to manage moderate to severe Inflammatory Bowel Disease (IBD) has revolutionized disease management. However, the cost of medication has been found to be the greatest contributor to medical costs. Furthermore previous studies have found that the highest economic burden of IBD was in patient populations ages 40 and older. Given the cost and the bimodal distribution of diagnosis of IBD, our study aims to evaluate the impact of insurance status on mortality rates between patients ages 18-40 and ages 65 and older. Methods: The National Inpatient Sample (NIS) database (2016-2020) was analyzed to identify adult patients admitted with ICD-10 codes for IBD. Multivariate logistic/linear regressions were used to compare effects of insurance status (Private insurance, no insurance, Medicare, Medicaid) on mortality outcomes, length of stay (LOS), and total hospital charges (TOTCHG) in two patient populations: younger patients ages 18-40 and older patients ages 65 and older. Patient age, race, gender, Charlson Comorbidity Index (CCI) were controlled. Weighted analysis using Stata 17 MP was performed. Results: A total of 313,778 adult patients were identified with IBD. We found patients that were 18 to 40 years old with IBD (YIBD) with private insurance had a significantly lower mortality rate (OR 0.52, P< 0.05, CI 0.35-0.78) and LOS (-0.65 days, P< 0.01, CI -0.82- -0.48) when compared to YIBD patients that were uninsured despite not having a significant TOTCHG. However, YIBD patients with no insurance also had a shorter LOS (-0.68 days, P< 0.01, CI -0.88- -0.48) and lower TOTCHG (-$10,816.61, P< 0.01, CI -$16814.19- -$4819.03). We found that patients with IBD with ages over 65 (OIBD) with private insurance (OR 1.27, P< 0.01, CI 1.12-1.45) and no insurance (OR 2.20, P< 0.01, CI 1.81-2.68) had significantly higher mortalities compared to those with Medicare. However, OIBD patients with Medicaid had a significantly longer LOS (+1.69 days, P< 0.01, CI 0.91-2.47) and TOTCHG (+$16,790.02, P< 0.05, CI $2252.89-$31,327.14) compared OIBD patients with Medicare. Conclusions: We found that YIBD patients with private insurance had a significantly lower mortality rate and LOS compared to uninsured YIBD patients. However, OIBD patients with private insurance and no insurance actually had much higher mortalities compared to those with Medicare. Furthermore, uninsured YIBD patients had a shorter LOS and lower TOTCHG. In comparison, it was the OIBD patients with Medicaid that had longer LOS and higher TOTCHG compared to patients with Medicare. We found that differences in insurance statuses have profound effects on mortality, LOS, and TOTCHG particularly between younger and older populations. Given the current rise of biologic usage and even dual biologic usage in treatment of moderate to severe IBD, it is important to consider the effects of insurance status on clinical outcomes. Further investigation should be targeted towards identifying underlying causes behind these disparities and economical treatment methods for patients of all insurance statuses.