Burden of glucocorticoid use in commercially insured adults with generalized myasthenia gravis in the United States: A retrospective claims-based analysis

Generalized myasthenia gravis (gMG) is a chronic autoimmune condition characterized by muscle weakness. If frontline treatments inadequately manage symptoms, patients may require use of glucocorticoids (GC); however, long-term use of GCs is associated with toxicities. Few studies have examined the incidence of GC-related toxicities and economic burden among patients with gMG. This study aims to describe GC toxicities, healthcare resource utilization, and costs among US adults with gMG, stratified by level of GC use. Adults with gMG were identified using IQVIA PharMetrics® Plus data and classified into 2 mutually exclusive cohorts based on GC use during the most recent 12 months of health plan enrollment (study period): "no GC use" (no GC fills) or "any GC use" (≥1 GC fill). The "any GC use" cohort was stratified into "≥5 mg/d" (mean prednisone equivalent daily dose ≥5 mg) and "≥10 mg/d" (mean prednisone equivalent daily dose ≥10 mg) subgroups. GC use, incident GC toxicities, and all-cause healthcare resource utilization and costs were described during the study period for each cohort and subgroup. Among 8833 patients with gMG, 5076 (57.5%) had no GC use and 3757 (42.5%) had any GC use (≥5 mg/d: 1537 [40.9%]; ≥10 mg/d: 860 [22.9%]). Use of nonsteroidal immunosuppressants was higher among patients with GC use than those without (37.6% any GC use vs 19.6% no GC use). Incident GC toxicities were higher in patients with any GC use than those without (61.9% vs 52.3%). Common acute toxicities included nausea and vomiting, pneumonia, fungal infections, sepsis, and urinary tract infection; chronic toxicities were dyslipidemia, sleep disturbances, obesity, cardiac arrhythmias, and hypertension. Annual all-cause costs were >2x higher among patients with any GC use than those with no GC use ($76,381 vs $35,309). GC acute and chronic toxicities and costs tended to increase with increasing GC use. Since claims data do not contain reasons for diagnoses, toxicities could not be confirmed to be related to GC use. Additionally, results may be confounded by disease severity or concomitant medications. Effective GC-sparing treatments are needed to mitigate the clinical and economic burden of GC use in adults with gMG.