IBD AND RHEUMATOLOGICAL DISEASE OVERLAP IN A PREDOMINATELY AFRICAN AMERICAN CLINIC POPULATION AS COMPARED TO A NATIONAL INPATIENT DATABASE
Authors: Almujarkesh Mohamad Khaled , Haider Maryam , Kaur Jasleen , Abu-Heija Ahmad , Naylor Paul , Sarakbi Housam , Mutchnick Milton 
Published: January 2023

Abstract

INTRODUCTION
Extraintestinal manifestations (EIM) of inflammatory bowel disease (IBD) are common and can involve nearly any organ. EIM can cause a significant impact on morbidity and quality of life and can be a challenge to physicians to manage IBD patients.
Arthropathies occur in 6–53% of IBD patients and is considered the most common EIM. This study compares IBD- Rheumatological overlap in our university clinic with inpatients identified via the NIS database. We also evaluated the overlap in our clinic population concerning patient care. The objective of the study was to further characterize IBD-Rheumatological overlap by comparing our institution’s clinic population to patients identified via the NIS database.

METHODS
We used ICD-10 codes to identify IBD patients and further used a broad range of ICD-10 codes for rheumatological manifestation to identify overlapping patients in 2018 in our clinic population, the inpatient database population and NIS database. Incidence of coordinated care was determined in the clinic population.

RESULTS
In the clinic population there were 228 IBD patients and 2240 rheumatologic patients. Dual ICD-10 codes were found for 46 patients and further analysis resulted in 21 clinic patients with true overlap and recent visits (21/228 = 9.2%). For the inpatient analysis, there were 65,379 IBD patients with 3741 having a diagnosis for a rheumatologic disease (3741/65,379= 6%). In the clinic population, the majority of patients had diagnosed Crohn’s Disease (95.2%), were female (60%) and were African American (77%). The most common rheumatological manifestation was AS. While the inpatient data analysis also suggests that AS is more likely to be associated with Crohn’s Disease (0.64 % vs 0.43%), the most frequent manifestation was the general category of RA (3.54% vs 3.03%)
In the National inpatient database, 22,552 patients had a diagnosis of UC out of which 81% were Caucasian, 10% African American, and 9% Hispanic. There were 38,962 patients with Crohn’s disease out of which 82% were Caucasian, 15.2% African American and 7% were Hispanic. The most common rheumatological manifestation was RA.

DISCUSSION
In the clinic population study where rheumatological disease was well characterized by experienced rheumatologists, the most frequent disease was AS and the primary IBD manifestation was Crohn’s disease. In the inpatient population, rheumatological disease in general was present in 6% of patients but it is unknown if more specific rheumatological evaluation was performed on the patients.
The fact that the majority of clinic patients were seen by both GI and Rheumatology and were on effective therapies for their IBD and Rheumatological manifestations is encouraging. Both gastroenterologists and rheumatologists should be vigilant to identify the co-existence of these conditions and follow-up these patients for better outcomes.