Initial predictors of skin thickness progression in patients with diffuse cutaneous systemic sclerosis: Results from a multicentre prospective cohort in Japan

Abstract

Objective

To identify initial parameters that predict worsening of skin thickening in patients with diffuse cutaneous systemic sclerosis (dcSSc) using a multicentre, prospective, observational cohort in Japan.

Methods

A total of 171 patients with dcSSc were selected from a prospective cohort database based on the following criteria: dcSSc, modified Rodnan total skin thickness score (mRSS) ≥7, disease duration <60 months, and valid mRSS data at one year. Worsening of skin thickness was defined as an increase in mRSS ≥3 points and an increase ≥25% from baseline to one year. Initial demographic and clinical parameters useful for predicting the progression of skin thickness were identified using univariate and multivariable analysis, and prediction models of skin thickening progression were built based on combinations of independent predictive parameters.

Results

Only 23 patients (13.5%) experienced worsening mRSSs at one year. Short disease duration, low mRSS, absence of nailfold bleeding, arthritis, and a high erythrocyte sedimentation rate at diagnosis were identified as predictors of subsequent worsening of the mRSS even after adjusting for the treatment. Assessment of the best predictive model revealed that patients with a disease duration ≤12 months and mRSS ≤19 had a risk of mRSS worsening within one year, with a sensitivity of 73.9% and specificity of 81.1%.

Conclusion

Identification of predictors of subsequent worsening of skin thickness in dcSSc patients is useful for identifying patients who require intensive treatment with potential disease-modifying agents and for improving clinical trial design by characterizing eligible progressors in the Japanese population.

Keywords:

• Prediction model
• skin sclerosis
• scleroderma
• systemic sclerosis

Acknowledgements

The authors are grateful to all the patients who participated and the physicians who contributed to assembling the data at each participating centre.

Author contributions

MK, MH, and KT conceived and designed the study; RF and YS conducted the statistical analyses; MK, MH, OI, HE, FO, DG, YK, SS, HI, and KT collected data; and all authors participated in the interpretation of the study results and in the drafting, critical revision, and approval of the final version of the manuscript.

Conflicts of interest

MK has received research grants from Actelion and consulting fees from AbbVie, Bayer, Boehringer-Ingelheim, Chugai, Corbus, Galapagos, GlaxoSmithKline, and CSL Behring and serves on the speaker bureaus for Actelion, Boehringer-Ingelheim, and Chugai. The other authors have nothing to disclose.

Additional information

Funding

This work was supported by funds for research on intractable diseases from the Ministry of Health, Labour, and Welfare of Japan.