Pain is Common in Myositis and Associated with Disease Activity

Anjana Chandrasekhara Pillai; Tissa Bijoy George; Ren Dianxu; Siamak Mogadham-Kia; Chester V Oddis; Shiri Keret; Rohit Aggarwal

doi:10.1093/rheumatology/keae126

Pain is Common in Myositis and Associated with Disease Activity

Rheumatology (Oxford). 2024 Feb 26:keae126. doi: 10.1093/rheumatology/keae126. Online ahead of print.

Authors

Anjana Chandrasekhara Pillai¹, Tissa Bijoy George¹, Ren Dianxu¹, Siamak Mogadham-Kia², Chester V Oddis², Shiri Keret³, Rohit Aggarwal²

Affiliations

¹ Department of Internal Medicine, UPMC McKeesport, Pittsburgh, PA, USA.
² Division of Rheumatology and Clinical Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
³ Rheumatology unit, Bnai Zion Medical Center, Haifa, Israel.

PMID: 38410059
DOI: 10.1093/rheumatology/keae126

Abstract

Background: Understanding pain in myositis remains challenging. This study aimed to assess patient-reported pain and its correlation with myositis core set measures (CSMs), patient-reported outcomes (PROs), and functional measures.

Methods: Fifty subjects underwent baseline, 3-month, and 6-month assessments, evaluating myositis CSMs, functional measures, and patient-reported outcomes. Pain was measured using three methods: (1) a 10-cm Visual Analogue Scale (VAS), (2) pain score from the HAQ-DI, and (3) SF-36 (Short Form survey) pain questions. Correlations between disease activity measures and pain were examined at baseline, and changes in both were assessed at 6 months, along with longitudinal change of pain. The change in pain was also correlated with the published 2016 ACR/EULAR myositis response criteria, physician/patient's assessment of change.

Results: Nearly half of patients (45%) reported moderate to severe pain in all 3 pain scales, with higher severity of pain in PM/NM subset. At baseline, pain severity showed a strong correlation with most CSMs, PROs and functional outcomes in all the 3 pain scales and similar trends were noted for change in pain at the 6 months. On longitudinal analysis, the physical function scores and fatigue showed strong correlation with pain. Pain improved in myositis patients with improvement in disease activity over time.

Conclusions: Pain is common in myositis and is associated with multiple measures of disease activity, PROs, and functional outcomes in myositis. Most importantly pain improves with improvement in disease activity. SF-36 pain questions have good psychometric properties.

Keywords: HAQ-DI; Pain; SF-36; VAS; core set measures; dermatomyositis; fatigue; polymyositis.