Very-low-dose glucocorticoid therapy in rheumatoid arthritis: impact of b/tsDMARDs initiation timing on glucocorticoid withdrawal

<bold>Objectives: </bold>We investigated the effectiveness and safety of very low-dose (<5 mg daily) glucocorticoids (GCs) in patients with RA treated with biological and targeted synthetic disease-modifying anti-rheumatic drugs (b/tsDMARDs). <bold>Methods: </bold>In this prospective cohort study, we included all RA patients who started their first b/tsDMARDs at our institution between 2015 and 2020 and were monitored every 6 months for 3 years. Relationships between exposure to very low-dose GCs and disease activity were examined through multivariable logistic regression and repeated-measures analysis of variance. The impact of very low-dose GCs on safety was also evaluated. <bold>Results: </bold>We enrolled 229 RA patients, of whom 68% were prescribed very low-dose GCs and 32% received no GCs. After three years on b/tsDMARDs, 32% had never abandoned, 20% had gone on and off, and 23% had permanently discontinued very low-dose GCs, while 25% had never taken GCs. Shorter disease duration at b/tsDMARD initiation was the single modifiable predictor of very low-dose GCs cessation (OR 1.1, 95% CI 1.03-1.14 for any 1-year decrease; p= 0.001). A significant association existed between ongoing utilization of very low-dose GCs and persistent moderate disease activity. Use of very low-dose GCs was associated with hypertension (20% vs 11%) and myocardial infarction (2.3% vs 0%). <bold>Conclusion: </bold>A substantial proportion of RA patients treated with b/tsDMARDs continue to receive very low-dose GCs without significantly improving disease control. However, this appears to increase cardiovascular morbidity.