(004) Clinical and Economic Burden of Polymyalgia Rheumatica in Patients with an Inadequate Response to Glucocorticoids or Glucocorticoids Taper in a Real-World Setting

Background: Glucocorticoids (GCs) are the primary therapy for polymyalgia rheumatica (PMR). Nearly 50% of patients experience flares upon GC taper/discontinuation. The burden of continuing GC in such cases may offer insight into the value of GC-sparing therapies.

Objectives: To assess the clinical and economic outcomes of continuing GC in PMR patients who have an inadequate response (IR) to GC or GC-taper.

Methods: A new-onset PMR cohort from Medicare claims identified from 10/1/2016 to 12/31/2019 included patients age ≥50, with no PMR/ giant cell arteritis history and 1) ≥1 inpatient or ≥2 outpatient claims for PMR ≥30 days (D) to < 365D apart, 2) GC initiation 7.5–25 mg/D < 30D after 1st inpatient or from 1st outpatient code to 30D after 2nd code with GC dose ≥200 mg in 1st ≤30D GC use ≥4 months (Mo), 3) enrollment ≥1 year before index and 4) ≥2 years follow-up. Index date was the latter of diagnosis or GC criteria being met. Patients with seropositive rheumatoid arthritis, other rheumatic disease, organ transplant, multiple sclerosis, treatment for malignancy or conventional immunomodulatory drugs/interleukin-6 receptor inhibitors during baseline were excluded. Patients were split into two groups 1) IR to GC/GC taper: presumed flare if GC dose ≥7.5 mg/D at 6 Mo or GC use >12 Mo or relapse if GC used after discontinuation (>60D gap) or 2) non-IR to GC/GC taper.
All-cause healthcare resource utilization (HCRU) cost, and incidence rate of GC-related adverse events (GC-AEs) were reported from 6 Mo after index over 12 Mo intervals. For GC-AEs incidence rate, only the 1st event was counted except hospitalized infections and fractures. Poisson methods were used to estimate event rates/100 patient-years (PY). A subgroup analysis of the IR group estimated outcomes by cumulative GC dose quartiles.

Results: This analysis included 6054 PMR patients (65.4% females) with mean age 77.1 years. All-cause HCRU cost was higher in IR vs non-IR (mean difference US Dollar: 4781, 6051, 4168, and 6461 at >6–18, >18–30, >30–42, and >42–54 Mo) and most GC-AE incidences were higher in the IR vs non-IR group (i.e., hospitalized infections events/100 PY: 26 vs 17, 25 vs 13, 19 vs 13 and 19 vs 15 at >6–18, >18–30, >30–42, and >42–54 Mo). In the IR group, all-cause HCRU cost, and most GC-AEs decreased over time and exhibited a GC dose-response relationship with most outcomes.

Conclusions: The clinical and economic burden of persistent GC use in PMR patients unable to taper GC or who relapse is significant, lasting appreciably after discontinuation. These results emphasize the need for effective GC-sparing therapies to mitigate the long-term impact of GCs.