BACKGROUND: Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare necrotizing small-to-medium vessel vasculitis with a relapsing-remitting course involving prodromal (various allergic reactions), eosinophilic (infiltration into organs), and vasculitic (widespread inflammation of small and medium blood vessels) phases, with symptoms depending on the affected organ. Using a retrospective analysis of US administrative health insurance claims data (Merative™ MarketScan® databases), we assessed the clinical burden of EGPA.
METHODS: Patients with newly diagnosed EGPA from 2017 to 2021 with ≥12 months of continuous pre-diagnosis health plan enrolment and ≥1 inpatient or ≥2 outpatient EGPA-related diagnoses (≥90 days apart, ICD-10-CM code M.30.1) were included. Follow-up was from date of first observed EGPA diagnosis (index date; ID) until health plan disenrollment or database end. Major and non-major comorbidities and symptoms were analyzed in patients with EGPA and in a general population cohort matched on demographic characteristics.
RESULTS: In total, 236 patients with EGPA were identified (‘EGPA cohort’); 88% had commercial insurance. At ID, mean (standard deviation [SD]) age was 50.4 (14.5) years, 88% were <65 years and 58% were female. Mean (SD) duration of follow-up from ID was 21.7 (14.6) months; 26% had ≥30 months’ follow-up. Of these, 213 patients with EPGA (‘matched EGPA cohort’) were matched to a general population cohort (‘matched general population cohort’; N=779; mean [SD] age 50.6 [13.7] years, 90% were <65 years, 59% were female). The most common comorbidities at ID in the EGPA cohort were asthma (74% of patients), allergic rhinitis (57%), throat and chest pain (46%), and dyslipidemia (42%) (Table 1). After the ID, 79.2% of patients in the EGPA cohort reported ≥1 new EPGA symptom, with 31.4% experiencing a major symptom, of which the most common was hematuria (8.1%). In the matched EGPA cohort, 44% of patients had major symptoms, the most common of which were respiratory failure (19%), hematuria (9%), hemoptysis/alveolar hemorrhage (6%) and cardiomyopathy (6%). More patients in the matched EGPA cohort had a major symptom compared with the matched general population cohort at ID (prevalence ratio 8.0 [95% CI 5.8–11.1]; p<0.001) as well as new symptoms after ID (prevalence ratio 3.0 [95% CI 2.2–4.0]; p<0.001) (Table 2). The symptoms with the three highest prevalence ratios in the matched EGPA cohort versus the matched general population cohort at ID were respiratory failure (73.1 [17.8–300.2]; p<0.001), hemoptysis or alveolar hemorrhage (23.8 [5.4–104.5]; p<0.001) and congestive heart failure (21.9 [4.9–97.3]; p<0.001).
CONCLUSIONS: At ID, over 40% of patients with EGPA had major symptoms. New EGPA events continued to occur after ID, with many occurring significantly more frequently than in a matched population without EGPA. These data highlight the substantial burden of EGPA, with a large portion of symptoms within the respiratory system. Greater awareness of EGPA symptoms is needed to ensure proper disease management between different specialties and multidisciplinary teams.
