Background Granulomatosis with polyangiitis (GPA), an ANCA-related vasculitis, is a severe condition that can result in organ damage and death.
Objectives The objective was to describe the clinical and economic burden of patients with GPA in the US.
Methods A retrospective claims-based cohort study was conducted using MarketScan® Commercial and Medicare Supplemental Databases in the period of 2009-2013. Inclusion criteria were: ≥2 claims with an ICD-9-CM diagnosis code for GPA (446.4), with date of first claim defined as index date; ≥18 years old at index date; and continuous enrollment for 12 months after index date. Incident cases were defined as patients with 12 months of continuous enrollment prior to index date with no diagnosis code for GPA. Major relapse-related events were defined via input from a clinical expert. Patient characteristics, all-cause and GPA-specific healthcare resource use and costs (inflated to US$ 2013) were reported. Descriptive analyses of all outcomes were stratified by incident and prevalent GPA cases.
Results 2784 patients met the study criteria (2215 prevalent cases, 569 incident cases). Mean age was 56.4 years, study population was 54% female, and post-index Charlson Comorbidity Index was 1.6. The most common physician specialty on the index date for GPA patients was primary care (26%), followed by rheumatology (24%). The most common post-index relapse-related diagnosis was acute or chronic renal failure (31%), followed by lung disease (8%). 12% of patients had at least one major relapse-related event in the post-index period. 25% of the patients had ≥1 hospitalization for any cause in the post-index period (22% GPA-related hospitalization). Among patients with ≥1 hospitalization, the mean number of inpatient admissions was 1.8 (1.7 GPA-related inpatient admissions). 32% of patients had ≥1 emergency room visit (7% GPA-related emergency room visits), and all patients had an outpatient visit or service (Figure). Mean total all-cause annual cost was $41,400. Mean total GPA-related annual cost was $24,319. On average, 58.7% of all–cause costs per GPA patient was associated with GPA.
Conclusions In the US, GPA is associated with significant healthcare resource use and is an important driver of cost of care. Reducing the risk of relapse can contribute to the decrease the clinical burden and total healthcare costs for this population. Future studies are needed to explore whether similar trends are seen in other countries.
Disclosure of Interest K. Raimundo Employee of: Genentech, Inc., A. Farr Employee of: Truven Health Analytics which performs consulting work for pharmaceutical companies, including Genentech, Inc., G. Kim Employee of: Truven Health Analytics which performs consulting work for pharmaceutical companies, including Genentech, Inc., G. Duna Employee of: Genentech, Inc.