Abstract Background Growing evidence supports the diagnostic accuracy and utility of intestinal ultrasound (IUS) in inflammatory bowel disease (IBD). However, few studies have explored the impact of IUS availability on diagnostic decision-making and healthcare costs, including whether there are differences between IBD-subtypes. This study evaluated whether access to IUS reduced magnetic resonance enterography (MRE) and colonoscopy use and estimated corresponding cost-savings. Methods This observational study was designed a priori using a prospectively maintained IUS referral database at a tertiary Australian IBD centre over 24 months. At referral, IBD clinicians indicated whether IUS was requested instead of or in addition to MRE and/or colonoscopy using a standardised electronic IUS referral form. “Instead of” was defined at referral as no corresponding MRE or colonoscopy within 3 months before or 6 months after IUS. Only IUS referrals designated for completion within 3 months were eligible to ensure that IUS referrals were clinically contemporaneous with substitution decisions. The primary outcome was investigation avoidance defined as the number of MRE and colonoscopy procedures not performed when IUS was requested as a substitute. Secondary outcomes were estimated healthcare cost-savings and differences between IBD subtype. Substitution of IUS for MRE and colonoscopy yielded savings of AUD599 and AUD2, 061, respectively. Results Among 427 referrals (Crohn’s disease: 70. 5%, ulcerative colitis: 19. 2%, suspected IBD: 10. 3%), IUS replaced 184 MREs and 130 colonoscopies over 24 months (Table 1). This resulted in estimated cost-savings of AUD378, 284 (MRE: AUD110, 315; Colonoscopy: AUD 267, 969), with colonoscopy-related savings 2. 4 times greater than those of MRE (Table 2). IUS referral patterns varied according to IBD subtype (Figure 1). In patients with Crohn’s disease, IUS was twice as likely to be requested instead of an MRE (65. 3%) compared to colonoscopy. In contrast, among patients with ulcerative colitis, IUS was requested instead of a colonoscopy in almost all cases (97. 7%). The estimated cost-saving associated with substituting IUS for MRE and colonoscopy were AUD261, 355 for Crohn’s disease and AUD87, 174 for ulcerative colitis. This indicates IUS use in Crohn’s disease yielded three times the cost savings compared to ulcerative colitis. Conclusion Integration of IUS into IBD care reduced the use of MRE and colonoscopy, resulting in cost-savings, mostly attributable to colonoscopy avoidance. Substitution patterns were disease subtype-specific, with IUS replacing MRE in Crohn’s disease and colonoscopy in ulcerative colitis. IUS is a clinically useful and cost-effective tool that helps reduce the health economic burden of IBD investigations. Conflict of interest: Dr. Srinivasan, Ashish: AS has served as a speaker for Arrotex Pharmaceuticals and has received advisory fees or conference support from AstraZeneca, AbbVie, Takeda Pharmaceuticals, and Dr Falk Pharma. Wong, Darren: No conflict of interest Porwal, Riva: No conflict of interest Schulberg, Julien: Grant: Falk Pharma Other: Abbvie - advisory board Grace, Josephine: No conflict of interest De Cruz, Peter: PDC is sup¬ported by an NHMRC Emerging Leader 2 Fellowship and has received research support from AbbVie, Ferring, Shire, Janssen, Pfizer, and Takeda.
Srinivasan et al. (Thu,) studied this question.