Domains and outcome measures for the assessment of limited cutaneous systemic sclerosis: an international collaborative scoping review

Composite measures to assess disease damage, disease severity and treatment response in systemic sclerosis clinical trials

PURPOSE OF REVIEW

The aim of this study was to summarize the composite outcome measures available to assess disease damage, severity and treatment response in systemic sclerosis (SSc).

RECENT FINDINGS

There have been many recent efforts to rigorously develop and validate composite outcome measures to assess the totality of the impact of SSc on patients. All initiatives have used both consensus and data-driven methods. Recently developed are a SSc-specific damage index, a patient-reported disease impact questionnaire (ScleroID) and a treatment response index (ACR-CRISS).

SUMMARY

Multiorgan, composite measures are being increasingly applied to assess treatment efficacy in clinical trials. Although a fully validated, disease-specific composite measure is not yet available, there has been significant recent progress towards developing measures of treatment response, damage and overall impact of SSc for application in randomized controlled trials.

The long-term course of the Health Assessment Questionnaire in patients with systemic sclerosis

Objective

The Health Assessment Questionnaire-Disability Index is an important outcome measure reflecting functional disability, but knowledge on its course over time in patients with systemic sclerosis is scarce. Therefore, we investigated the long-term course of the Health Assessment Questionnaire-Disability Index and its association with baseline characteristics in systemic sclerosis patients.

Methods

Systemic sclerosis patients, fulfilling the European League Against Rheumatism and the American College of Rheumatology 2013 criteria, were included from the Leiden Combined Care in Systemic Sclerosis cohort with annual assessments including the Scleroderma Health Assessment Questionnaire-Disability Index (range = 0-3). The course of the Health Assessment Questionnaire-Disability Index was evaluated over the total follow-up (baseline to last available Health Assessment Questionnaire-Disability Index) and between yearly visits. Based on a minimal clinical important difference of 0.22, courses were categorized into worsening, stable or improvement. The course of the Health Assessment Questionnaire-Disability Index over time was evaluated with linear mixed models. Baseline characteristics were compared between patients with a worsening or improvement of the Health Assessment Questionnaire-Disability Index over the total follow-up period with logistic regression analyses.

Results

A total of 517 systemic sclerosis patients were included, with a median follow-up of 7 years (interquartile range = 4-9; 2649 visits) and a baseline Health Assessment Questionnaire-Disability Index of 0.625 (interquartile range = 0.125-1.25). On group level, the Health Assessment Questionnaire-Disability Index is stable with an annual increase of 0.019 (95% confidence interval = 0.011 to 0.027). Looking at subgroups, patients >65 years or who died/were physically unable to come during follow-up had a worse mean Health Assessment Questionnaire-Disability Index. In individual courses from baseline to the last follow-up, the proportions of patients with a clinically meaningful worsening, stable or improved Health Assessment Questionnaire-Disability Index were 35%, 42% and 23%, respectively. Patients with immunosuppressants (odds ratio = 0.5, 95% confidence interval = 0.3 to 0.9) or gastrointestinal involvement (odds ratio = 0.6, 95% confidence interval = 0.4 to 0.9) at baseline showed a reduced chance of worsening of the Health Assessment Questionnaire-Disability Index over the total follow-up period.

Conclusion

Over time, the average course of the Health Assessment Questionnaire-Disability Index was stable in systemic sclerosis patients. However, individual courses vary, with worsening occurring in one-third. Worsening occurred less often in individuals using immunosuppressants or with gastrointestinal involvement at baseline.

Cutaneous Manifestations, Clinical Characteristics, and Prognosis of Patients With Systemic Sclerosis Sine Scleroderma: Data From the International EUSTAR Database

Importance

Systemic sclerosis (SSc) sine scleroderma (ssSSc) is a subset of SSc defined by the absence of skin fibrosis. Little is known about the natural history and skin manifestations among patients with ssSSc.

Objective

To characterize the clinical phenotype of patients with ssSSc compared with patients with limited cutaneous SSc (lcSSc) and diffuse cutaneous SSc (dcSSc) within the EUSTAR database.

Design, Setting, and Participants

This longitudinal observational cohort study based on the international EUSTAR database included all patients fulfilling the classification criteria for SSc assessed by the modified Rodnan Skin score (mRSS) at inclusion and with at least 1 follow-up visit; ssSSc was defined by the absence of skin fibrosis (mRSS = 0 and no sclerodactyly) at all available visits. Data extraction was performed in November 2020, and data analysis was performed from April 2021 to April 2023.

Main Outcomes and Measures

Main outcomes were survival and skin manifestations (onset of skin fibrosis, digital ulcers, telangiectasias, puffy fingers).

Results

Among the 4263 patients fulfilling the inclusion criteria, 376 (8.8%) were classified as having ssSSc (mean [SD] age, 55.3 [13.9] years; 345 [91.8%] were female). At last available visit, in comparison with 708 patients with lcSSc and 708 patients with dcSSc with the same disease duration, patients with ssSSc had a lower prevalence of previous or current digital ulcers (28.2% vs 53.1% in lcSSc; P < .001; and 68.3% in dcSSc; P < .001) and puffy fingers (63.8% vs 82.4% in lcSSc; P < .001; and 87.6% in dcSSc; P < .001). By contrast, the prevalence of interstitial lung disease was similar in ssSSc and lcSSc (49.8% and 57.1%; P = .03) but significantly higher in dcSSc (75.0%; P < .001). Skin telangiectasias were associated with diastolic dysfunction in patients with ssSSc (odds ratio, 4.778; 95% CI, 2.060-11.081; P < .001). The only independent factor for the onset of skin fibrosis in ssSSc was the positivity for anti-Scl-70 antibodies (odds ratio, 3.078; 95% CI, 1.227-7.725; P = .02). Survival rate was higher in patients with ssSSc (92.4%) compared with lcSSc (69.4%; P = .06) and dcSSc (55.5%; P < .001) after up to 15 years of follow-up.

Conclusions and Relevance

Systemic sclerosis sine scleroderma should not be neglected considering the high prevalence of interstitial lung disease (>40%) and SSc renal crisis (almost 3%). Patients with ssSSc had a higher survival than other subsets. Dermatologists should be aware that cutaneous findings in this subgroup may be associated with internal organ dysfunction. In particular, skin telangiectasias in ssSSc were associated with diastolic heart dysfunction.