Impact of Age and Teaching Hospital Status on Outcomes in Hemolytic Uremic Syndrome: An Analysis Using the NIS 2021 Database Abstract
Authors: Babu Kalaivani , Rajarajan Srinishant , Ramanan Sruthi P , Ramesh Nithya , Correa Amit , Ayanambakkam Attanathi Adanma Anji , Nusrat Sanober , Roy Arya Mariam , Chattaraj Asmi , Helfand Alexander 
Published: December 2024

Abstract:
Background:
This study investigates the impact of age and treatment at teaching hospitals on hospitalization charges, mortality rates, and length of stay in patients diagnosed with Hemolytic Uremic Syndrome (HUS). The analysis utilizes data from the 2021 National Inpatient Sample (NIS) database.
Methods:
A diagnosis of HUS was identified using the appropriate ICD-10 codes. Demographic data, including gender, race, and hospital teaching status, were analyzed. The study employed multivariate regression models to evaluate the outcomes, using STATA programming. Linear regression was used for analyzing total hospitalization charges and length of stay, while logistic regression was used for mortality analysis. The sample consisted of adult patients hospitalized with HUS, with data weighted to represent the U.S. population.
Results:
A total of 2,290 adult patients admitted to the hospital with HUS were identified from the NIS 2021. The cohort was comprised of 60% female and 40% male patients. The racial distribution was as follows: 56.04% White, 25.74% Black, 9.57% Hispanic, 4.33% Asian or Pacific Islander, 0.23% Native American, and 4.1% Other. The overall mortality rate among these patients was 7.0%, translating to approximately 160 deaths. A one-year increase in age was associated with a 4.4% increase in mortality odds (p&lt;0.01).
Treatment at teaching hospitals was associated with higher charges, with a coefficient of 105703.5 (p=0.039). The coefficients for hospital bed size were 14582.49 (p=0.788) for medium and 102051.8 (p=0.085) for large, indicating no significant impact. Additionally, a one-year increase in age was associated with an increase of $3,456 in charges (p=0.039) and a 0.11-day increase in length of stay (p=0.021). Patients treated at teaching hospitals also had longer stays by an average of 3.29 days compared to those at non-teaching hospitals (p=0.046).
Age was significantly associated with an increase in total charges, with a coefficient of $3456.079 (p=0.039). Gender did not have a significant impact on charges, with a coefficient of -36299.21 (p=0.345). For race, the coefficients were 43053.77 (p=0.518) for Black, 35038.42 (p=0.690) for Hispanic, and 276656.1 (p=0.217) for Asian or Pacific Islander, indicating no significant differences. The third quartile of income was associated with a significant negative effect on charges, with a coefficient of -131706.7 (p=0.020). The Charlson Comorbidity Index had a coefficient of -13550.48 (p=0.237), indicating no significant impact.
Conclusion:
In patients with Hemolytic Uremic Syndrome, both age and treatment at teaching hospitals are associated with higher hospitalization charges, increased mortality odds, and longer hospital stays. The results indicate that older patients and those treated in teaching hospitals may require more intensive care or experience more complications, leading to higher costs and longer hospital stays. Further research is warranted to explore the factors that significantly influence key healthcare outcomes in this patient population.