Aortic Stenosis Is Associated With Worse Outcomes in Patients Admitted With Lower Gastrointestinal Bleeding

Introduction: The association between aortic stenosis (AS) and lower Gastrointestinal bleeding (LGIB) has been described in various studies, however very few reports have described the prognostic implications of lower GI bleeding in patients with AS. Our study aims to ascertain the in-hospital outcomes of AS patients who were admitted to the hospital with a principal diagnosis of lower GI bleeding using a national representative sample. Methods: A retrospective analysis of patients admitted for Lower GI bleeding from 2016 – 2019 using the National Inpatient Sample (NIS) was conducted. ICD 10 codes were used to Identify individuals with Lower GI bleeding which were further divided into 2 groups based on the presence or absence of a history of AS. Following control for confounders, we compared the risk of in hospital mortality and other outcomes including artery embolization, hypovolemic shock, frequency of blood transfusion, Length of stay and total hospitalization charges amongst both groups. Results: There were 250,895 patients admitted with LGIB and 3% (6950) had co existing Aortic stenosis. There were a greater proportion of females (51%) presenting with AS and lower GI bleeding. Mean age of presentation was also noted to be higher in the Aortic stenosis group vs no aortic stenosis (82.2 ± 0.4 vs 74.4 ± 0.2) respectively. Comparing both groups of patients, we observed that there was a significantly increased risk of in hospital mortality in the AS group (AOR 1.85, 95% CI 1.2-2.7, p = 0.03). We also observed a statistically significant increase in the length of stay (Adjusted coefficient 0.5, 95% CI 0.3 -0.7, p = 0.00), Total hospitalization charges (Adjusted coefficient 6173, 95% 3211-9134.52, p = 0.00) and frequency of blood administration (AOR 1.32, 95% CI 1.16-1.50, p = 0.00) amongst the AS group. There was no significant increase in the incidence of hypovolemic shock (AOR 1.07, 95% CI 0.75-1.54, p = 0.698) or utilization of lower gastrointestinal artery embolization (AOR 0.88, 95% CI 0.22 -3.56, p = 0.868). Conclusion: This study showed worse in-hospital outcomes in patients admitted for lower GI bleed and co-morbid aortic stenosis with an increased risk of In-hospital mortality, blood transfusion, length of stay and total hospitalization charges.