Trajectory analysis of glucocorticoid treatment highlights issues in the current tapering strategy for polymyalgia rheumatica.

OBJECTIVES

To identify glucocorticoid (GC) treatment patterns in patients with polymyalgia rheumatica (PMR) and explore patient profiles that may benefit from GC-sparing interventions.

METHODS

This descriptive study was conducted using an electronic medical record database in Japan. We identified patients with PMR aged ≥50 years who were initiated 5-<30 mg/day of GCs with increased inflammatory markers. Group-based trajectory modelling (GBTM) was used to characterise GC treatment patterns over 52 weeks. We analysed clinical characteristics, including changes in GC doses, longitudinal C-reactive protein levels, immunosuppressant use and GC-related toxicities.

RESULTS

Among 452 eligible patients with PMR, four treatment trajectories were identified: rapidly-declining (19.0%), low-dose (36.9%), intermediate-dose (32.5%) and high-dose (11.5%). The rapidly declining and low-dose groups had more patients aged ≥80 years and with comorbidities. The median doses at week 52 in the low-dose, intermediate-dose and high-dose groups were 3.0, 4.0 and 7.5 mg/day, respectively. These groups had higher cumulative doses and greater GC-related toxicities compared with the rapidly declining group, which was reduced to 0 mg/day by week 8. The cumulative incidence of immunosuppressant use at week 52 was 6.1%-10.5%, even in the high-dose group.

CONCLUSIONS

GBTM analysis indicates that many patients who do not discontinue GC use within 1 year are exposed to high cumulative GC doses, which are associated with an elevated risk of GC-related toxicities. Our findings highlight the need to reconsider treatment strategies for patients with PMR, including the use of GC-sparing agents.