The clinical outcomes and healthcare resource utilization in IgG4-related disease: a claims-based analysis of commercially insured adults in the United States

Zachary S Wallace; Gandarvaka Miles; Ekaterina Smolkina; Natalia Petruski-Ivleva; Duane Madziva; Krishan Guzzo; Claire Cook; Xiaoqing Fu; Yuqing Zhang; John H Stone; Hyon K Choi

doi:10.1093/rheumatology/keae230

The clinical outcomes and healthcare resource utilization in IgG4-related disease: a claims-based analysis of commercially insured adults in the United States

Rheumatology (Oxford). 2024 Apr 19:keae230. doi: 10.1093/rheumatology/keae230. Online ahead of print.

Authors

Zachary S Wallace^{1

2}, Gandarvaka Miles³, Ekaterina Smolkina⁴, Natalia Petruski-Ivleva³, Duane Madziva⁵, Krishan Guzzo¹, Claire Cook¹, Xiaoqing Fu¹, Yuqing Zhang^{1

2}, John H Stone^{1

2}, Hyon K Choi^{1

2}

Affiliations

¹ Division of Rheumatology, Allergy, and Immunology, Massachusetts General Hospital, Boston, MA, US.
² Harvard Medical School, Boston, MA, US.
³ Sanofi, Cambridge, MA, US.
⁴ Sanofi, Amsterdam, The Netherlands.
⁵ Sanofi, Mississauga, Ontario, Canada.

PMID: 38637947
DOI: 10.1093/rheumatology/keae230

Abstract

Objectives: IgG4-related disease (IgG4-RD) can affect nearly any organ and is often treated with glucocorticoids, which contribute to organ damage and toxicity. Comorbidities and healthcare utilization in IgG4-RD are poorly understood.

Methods: We conducted a cohort study using claims data from a United States managed care organization. Incident IgG4-RD cases were identified using a validated algorithm; general population comparators were matched by age, sex, race/ethnicity, and index date. The frequency of 21 expert-defined clinical outcomes associated with IgG4-RD or its treatment and healthcare-associated visits and costs were assessed 12 months before and 36 months after the index date (date of earliest IgG4-RD-related claim).

Results: There were 524 cases and 5,240 comparators. Most cases received glucocorticoids prior to (64.0%) and after (85.1%) the index date. Nearly all outcomes, many being common glucocorticoid toxicities, occurred more frequently in cases vs comparators. During follow-up, the largest differences between cases and comparators were seen for gastroesophageal reflux disease (prevalence difference: +31.2%, p< 0.001); infections (+17.3%, p< 0.001); hypertension (+15.5%, p< 0.01); and diabetes mellitus (+15.0%, p< 0.001). The difference in malignancy increased during follow-up from +8.8% to + 12.5% (p< 0.001). 17.4% of cases used pancreatic enzyme replacement therapy during follow-up. Over follow-up, cases were more often hospitalized (57.3% vs 17.2%, p< 0.01) and/or had an ER visit (72.0% vs 36.7%, p< 0.01); all costs were greater in cases than comparators.

Conclusions: Patients with IgG4-RD are disproportionately affected by adverse outcomes, some of which may be preventable or modifiable with vigilant clinician monitoring. Glucocorticoid-sparing treatments may improve these outcomes.

Keywords: Comorbidity; Cost; Epidemiology; IgG4-RD.