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Anti-SS-A/Ro antibody positivity as a risk factor for relapse in patients with polymyositis/dermatomyositis
Noriko Tatebe1, Ken-Ei Sada1, Yosuke Asano1
1a Department of Nephrology, Rheumatology, Endocrinology and Metabolism , Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences , Okayama , Japan.
Objective:
The objective of this study is to elucidate predictors of relapse in patients with polymyositis and dermatomyositis (PM/DM).
Methods:
Fifty PM/DM patients who achieved disease stabilization at Okayama University Hospital in 2004-2014 were enrolled retrospectively. Candidate predictors such as demographic factors, clinical symptoms, laboratory data, and treatment status were compared.
Results:
The mean age of enrolled patients was 58 years; 34 were female. The patient groupings were as follows: 21 with PM, 27 with DM, and two with clinically amyopathic DM. During a mean observation period of 685 d, 5 patients (10%) died and 20 (40%) relapsed. The relapsed patients displayed baseline muscle weakness less frequently (85% versus 100%, p = .03) and anti-SS-A/Ro antibody more frequently (65% versus 27%, p = .007). Anti-SS-A/Ro-positive patients exhibited a higher relapse rate than anti-SS-A/Ro-negative patients (log-rank test, p = .03). Anti-SS-A/Ro-positive patients also exhibited higher anti-Jo-1 antibody positivity and lower levels of serum complement. After adjusting anti-Jo-1 antibody positivity, age, sex, CK <500 IU/L, and lung involvement, anti-SS-A/Ro positivity was still an independent risk factor for higher relapse-rate (odds ratio, 5.5; 95% confidence interval, 1.4-25.1).
Conclusions:
Anti-SS-A/Ro antibody positivity may be a useful biomarker for prediction of relapse.
Insights
Predicting relapse in polymyositis and dermatomyositis is crucial. Anti-SS-A/Ro antibody positivity is a key predictor of relapse in these inflammatory myopathies.
Area of Science:
- Rheumatology
- Immunology
- Internal Medicine
Background:
- Polymyositis and dermatomyositis (PM/DM) are chronic autoimmune diseases.
- Predicting relapse is essential for effective patient management and treatment strategies.
Purpose of the Study:
- To identify predictors of disease relapse in patients diagnosed with polymyositis and dermatomyositis.
- To investigate the association between baseline characteristics and relapse in PM/DM patients.
Main Methods:
- Retrospective analysis of 50 PM/DM patients achieving disease stabilization between 2004-2014.
- Comparison of demographic factors, clinical symptoms, laboratory data, and treatment status between relapsed and non-relapsed patients.
Main Results:
- A 40% relapse rate was observed during a mean follow-up of 685 days.
- Patients who relapsed were less likely to present with baseline muscle weakness (85% vs. 100%) and more likely to be positive for anti-SS-A/Ro antibodies (65% vs. 27%).
- Anti-SS-A/Ro antibody positivity was an independent risk factor for relapse (OR, 5.5; 95% CI, 1.4-25.1), even after adjusting for other factors.
Conclusions:
- Anti-SS-A/Ro antibody positivity serves as a potential biomarker for predicting relapse in PM/DM patients.
- Early identification of anti-SS-A/Ro positivity may aid in proactive management to prevent disease flares.
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