Long-Term Dysphagia Severity in Patients With Idiopathic Inflammatory Myopathy: A Single-Center Retrospective Study.

Objective To investigate long-term dysphagia severity and survival outcomes in patients with idiopathic inflammatory myopathy (IIM). Methods We retrospectively included consecutive Japanese patients with IIM between April 2000 and March 2022. The primary endpoint was the complete oral intake rate according to the Food Intake LEVEL Scale (FILS) within one year after the onset of dysphagia in patients with IIM.The secondary outcome was the overall mortality rate in IIM patients with dysphagia.  Results Of the 108 patients with IIM, 18 (16.7%) developed dysphagia during the observation period. The baseline median dysphagia severity in IIM patients with dysphagia using the FILS was 7.0 and improved to 10.0 at the final observation. Almost all IIM patients recovered from dysphagia severity, and the complete oral intake rate within one year in IIM patients with dysphagia was 72.2%. The overall mortality rate of patients with IIM patients with dysphagia was 44.4%, which is significantly lower than that of those without dysphagia (P < 0.05). Cox regression analysis demonstrated that malignancy-associated myositis was a poor prognostic factor in patients with IIM and survival outcomes in IIM patients with dysphagia were poor compared with those in patients without dysphagia when with malignancies. Conclusions The dysphagia severity in patients with IIM improved; however, their survival rate was lower than that of those without dysphagia when malignancy occurred.