Long-term effects of early pulse methylprednisolone and intravenous immunoglobulin in patients with dermatomyositis and polymyositis

Objective To evaluate the long-term effects of pulse i.v. methylprednisolone (IVMP) or IVIG administered during the first year of diagnosis in DM and PM patients. Methods This is a retrospective single-centre cohort study of patients with PM/DM followed for up to 4 years from 2001 to 2017. We used Cox regression models to estimate hazard ratios (HRs) and assess the effects of early pulse IVMP or IVIG on three outcomes: complete clinical response, CS discontinuation, and survival. Analysis was adjusted for clinical, laboratory and treatment covariates. Results A total of 204 patients were included and categorized into four initial treatment groups: pulse IVMP (n = 46), pulse IVMP + IVIG (n = 55), IVIG (n = 10), and without IVMP or IVIG (n = 93). The groups of early pulse IVMP and pulse IVMP + IVIG had a higher HR for complete clinical response in the multivariate models (HR = 1.56, 95% CI: 1.05, 2.33, P = 0.029; and HR = 1.58, 95% CI: 1.02, 2.45, P = 0.041, respectively). Only the group of pulse IVMP + IVIG had a significant association with CS discontinuation in the multivariate analysis (HR = 1.65, 95% CI: 1.02, 2.68, P = 0.043). Early pulse IVMP or IVIG had no impact on mortality. Conclusion Despite having a more severe disease profile, patients with PM/DM submitted to pulse IVMP or pulse IVMP + IVIG during the first year of diagnosis had a higher HR for complete clinical response, whereas the combination of pulse IVMP + IVIG had an association with CS discontinuation. Prospective long-term studies are warranted to confirm these benefits of early pulse IVMP and IVIG on patients with PM/DM.

Automated summary

This study aimed to evaluate the long-term effects of pulse intravenous methylprednisolone (IVMP) or intravenous immunoglobulin (IVIG) in patients with dermatomyositis (DM) and polymyositis (PM) during the first year of diagnosis. The results showed that patients who received early pulse IVMP or pulse IVMP + IVIG had a higher hazard ratio for complete clinical response, while the combination of pulse IVMP + IVIG was associated with discontinuation of corticosteroids.