To investigate the determinants of health care utilization and costs with use of glucocorticoid (GC) drugs among adult systemic lupus erythematosus (SLE) patients.
This cross-sectional study analyzed established SLE patients identified by International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes from a large US insurance claims database in 2007-2011. Five patient groups were defined by their oral GC use during a 1-year period: non-GC users, <60 days of GC use, and ≥60 days of GC use in low dosage (≤7.5 mg/day), medium dosage (>7.5 to ≤15 mg/day), or higher dosage (>15 mg/day). Annual health care utilization and costs were compared across these groups. Incremental costs of GC groups, calculated as the difference in total health care costs compared with those of the non-GC group, were estimated from multivariable regressions adjusting for demographic/clinical characteristics and stratified by concomitant immunosuppressant use.
A total of 50,230 SLE patients were identified (52% non-GC users, 20% <60 days of GC use, and 10% low dose, 10% medium dose, and 8% higher dose of ≥60 days of GC use). GC users had higher health care utilization and costs. Incremental costs were significant (all P < 0.01) for medium-dose ($5,319 and $6,913) and higher-dose ($12,517 and $15,019) GC groups, regardless of concomitant immunosuppressant use. The incremental costs for the low-dose GC group with concomitant immunosuppressants ($1,285; P = 0.04) were smaller than the incremental costs for the low-dose GC group without concomitant immunosuppressants ($2,514; P < 0.01).
GC use, especially at higher doses, was associated with higher health care utilization and costs. Findings in users with concomitant immunosuppressants suggest that therapies with a GC-sparing effect may be associated with lower economic burden in SLE treatment.