P1079 - Why Do IBD Patients Experience Diagnostic Delays? A Tertiary Care Center Study of Patient Journeys Using Large Language Models

Mao-Yuan Chen, MD, Goktug Onal, , Aryan Ayati, MD, MPH, Anshu Mukherjee, , Vivek Rudrapatna, MD, PhD
University of California San Francisco, San Francisco, CA

Introduction: Timely diagnoses of inflammatory bowel disease (IBD) are necessary to initiate early effective treatment and ensure the best long-term outcomes. However, the root causes of diagnostic delays have remained poorly understood. Given the nuances of diagnosing and treating IBD, patient journeys often involve multiple providers and health systems. We sought to identify the root causes of diagnostic delays and explore potential opportunities for intervention.

Methods: We identified 406 adult patients newly diagnosed with IBD after 2012 from our center’s clinical data warehouse. The diagnosis date was operationally defined as the earliest date at which an IBD ICD code was assigned. We compiled all available inpatient, gastroenterology, and primary care de-identified notes dated from 3 years before up to 2 years after the diagnosis. A HIPAA-compliant o1 model was utilized to extract the earliest date of symptoms, route of discovery, and the first-ever gastroenterology and non-gastroenterology visit related to features of IBD. Large language model outputs were validated by manual review of a 10-patient random sample, showing 80–100% accuracy.

Results: In this cohort, 94% of IBD patients initially presented with a hallmark gastrointestinal symptom, while 6% were incidentally diagnosed (Figure 1A). In addition, 69% of the patients initially sought medical evaluation in primary care or non-gastroenterology specialties for IBD symptoms. The greatest delays, affecting more than 20% of the patients, occurred when transitioning from external gastroenterology services (median delay: 233 days) or primary care/non-gastroenterology specialties (median delay: 66 days) to in-system gastroenterology (Figure 1B). The median time from an in-system gastroenterology visit to an in-system endoscopy was 38 days.

Discussion: The transition from an external gastroenterology service to a tertiary center accounts for important delays for patients with features of IBD. In addition, facilitating the transition from primary care services to gastroenterology may also be potentially streamlined. Nevertheless, whether these delays stem from scheduling, insurance, uncaptured diagnosis that were reached externally, or other causes needs more granular investigation.


Figure: Figure 1. Diagnostic Delays for Patients with Newly Diagnosed IBD. A. The flow of transitions between the stages of care. The percentages indicate the proportion of patients in the transition (arrow), relative to the whole cohort. Transitions experienced by more than 20% of the cohort are labelled the extent of delay with plus (“+”) signs; higher number of plus signs indicate longer delays. Bold numbers 1–5 reference each transition to the corresponding cumulative curve in Panel B. B. The cumulative percentage of patients relative to days spent in each transition. Each number on the upper left corner of each grid indicates the transition in Panel A. Abbreviation: GI, gastroenterology service.

Disclosures:
Mao-Yuan Chen indicated no relevant financial relationships.
Goktug Onal indicated no relevant financial relationships.
Aryan Ayati indicated no relevant financial relationships.
Anshu Mukherjee indicated no relevant financial relationships.
Vivek Rudrapatna: Acucare – Advisory Committee/Board Member. Blueprint Medicines – Grant/Research Support. Data Unite – Advisory Committee/Board Member. Genentech – Grant/Research Support. Ironwood – Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events. Merck – Grant/Research Support. Microsoft – Grant/Research Support. Mitsubishi Tanabe – Grant/Research Support. Natera – Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events. Stryker – Grant/Research Support. Takeda – Grant/Research Support. ZebraMD – Advisory Committee/Board Member.

Mao-Yuan Chen, MD, Goktug Onal, , Aryan Ayati, MD, MPH, Anshu Mukherjee, , Vivek Rudrapatna, MD, PhD. P1079 - Why Do IBD Patients Experience Diagnostic Delays? A Tertiary Care Center Study of Patient Journeys Using Large Language Models, ACG 2025 Annual Scientific Meeting Abstracts. Phoenix, AZ: American College of Gastroenterology.