Autoantibodies and damage in patients with idiopathic inflammatory myopathies: A longitudinal multicenter study from the MYONET international network
Authors' conclusion
Patients with anti-PM/Scl scored a greater extent of damage, whereas patients with dermatomyositis-specific antibodies had less damage than seronegative patients. Severity in muscle damage had moderate to strong correlation with functional disability among the IMNM and seronegative subgroups with lower correlations for the other subgroups.
Study context
- Population
- Adults with idiopathic inflammatory myopathies (IIM) in the MYONET registry, tested for autoantibodies, with ≥1 Myositis Damage Index (MDI) damage assessment
- Participants
- 757 adult patients
- Exposure
- Autoantibody-defined subgroups vs seronegative
- Outcome
- Longitudinal trajectory of damage (Myositis Damage Index score) with autoantibody status as main predictor
Methodological detailsmulticentre, international registry (MYONET), linear mixed models
- Multicentre
- International registry (MYONET)
- Linear mixed models
Main finding
As reported in the abstract
MDI score change per year since diagnosis
Difference in annual MDI increase
0.08 less score
P = 0.04
DM-specific autoantibodies
Difference in annual MDI increase
0.28 higher score
P = 0.03
Anti-PM/Scl
- Estimated MDI increase per year of disease duration, seronegative (reference)
- 0.16 units
Observational data: associations, not effects.
Further findings
| Outcome | Seronegative |
|---|---|
| Correlation of muscle damage severity with HAQ-DI · 5 years of follow-up | rho 0.84 |
| P | P < 0.001 |
- Correlation of muscle damage severity with HAQ-DI: IMNM autoantibodies rho 0.72 · P P < 0.001
Correlation of muscle damage severity with HAQ-DI · 5 years of follow-up
- Lower correlations for the other subgroups
Original publication
Autoantibodies and damage in patients with idiopathic inflammatory myopathies: A longitudinal multicenter study from the MYONET international network. Semin Arthritis Rheum. Published 8 August 2024. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →