Summed and Weighted Summary Scores for the Medsger Disease Severity Scale Compared with the Physician’s Global Assessment of Disease Severity in Systemic Sclerosis

Contribution of Left Ventricular Diastolic Dysfunction to Survival and Breathlessness in Systemic Sclerosis-Associated Interstitial Lung Disease

OBJECTIVE

To explore the effect of left ventricular (LV) diastolic dysfunction (LVDD) in systemic sclerosis (SSc)-associated interstitial lung disease (ILD), and to investigate SSc-specific associations and clinical correlates of LVDD.

METHODS

There were 102 Australian Scleroderma Cohort Study participants with definite SSc and radiographic ILD included. Diastolic function was classified as normal, indeterminate, or abnormal according to 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines for assessment of LV diastolic function. Associations between clinical features and patient- and physician-reported dyspnea were evaluated using logistic regression. Survival analyses were performed using Kaplan-Meier survival estimates and Cox regression modeling.

RESULTS

LVDD was identified in 26% of participants, whereas 19% had indeterminate and 55% had normal diastolic function. Those with ILD and LVDD had increased mortality (hazard ratio 2.4, 95% CI 1.0-5.7; P = 0.05). After adjusting for age and sex, those with ILD and LVDD were more likely to have severe dyspnea on the Borg Dyspnoea Scale (odds ratio [OR] 2.6, 95% CI 1.0-6.6; P = 0.05) and numerically more likely to record World Health Organization Function Class II or higher dyspnea (OR 4.2, 95% CI 0.9-20.0; P = 0.08). Older age (95% CI 1.0-6.4; P = 0.05), hypertension (OR 5.0, 95% CI 1.8-13.8; P < 0.01), and ischemic heart disease (OR 4.8, 95% CI 1.5-15.7; P < 0.01) were all associated with LVDD, as was proximal muscle atrophy (OR 5.0, 95% CI 1.9-13.6; P < 0.01) and multimorbidity (Charlson Comorbidity Index scores ≥ 4, OR 3.0, 95% CI 1.1-8.7; P = 0.04).

CONCLUSION

LVDD in SSc-ILD is more strongly associated with traditional LVDD risk factors than SSc-specific factors. LVDD is associated with worse dyspnea and survival in those with SSc-ILD.

Patient and Physician Global Assessments of Disease Status in Systemic Sclerosis

Global assessments of disease by both patients and physicians are widely used in clinical studies of systemic sclerosis (SSc). They are commonly secondary end points in randomized controlled trials (RCTs) and are considered important items in composite measures of treatment response. A comprehensive literature review was conducted of the formats, wording, and clinimetric properties of the patient global assessment of disease status (PtGA) and physician global assessment of disease status (PhGA) used in RCTs of SSc. Marked heterogeneity was found in the wording and measurement scales of the global assessments applied in RCTs. These instruments were not developed using rigorous methodology and have not been fully validated. There is a pressing need for standardization and validation of patient and physician global assessment tools in SSc to enable universal application of these measures across RCTs in SSc.

Agreement Between Physician Evaluation and the Composite Response Index in Diffuse Cutaneous Systemic Sclerosis

OBJECTIVE

Diffuse cutaneous systemic sclerosis (SSc) is a highly heterogeneous disease. A provisionally approved Composite Response Index in diffuse cutaneous SSc (CRISS) was developed as a 1-year outcome measure for clinical trials. Our goal was to further validate the CRISS by examining agreement between CRISS definitions for improved/non-improved with physicians' evaluation of disease.

METHODS

Patient profiles from a large observational cohort were created for 50 random diffuse cutaneous SSc patients of <5 years disease duration with improved CRISS scores after 1 year and 50 with non-improved CRISS scores. Profiles described disease features used during the initial CRISS development at baseline and at 1 year. Each profile was independently rated by 3 expert physicians. Majority opinion determined whether a patient was improved or not improved, and kappa agreement with the CRISS cutoff of 0.6 was calculated.

RESULTS

Patients had mean ± SD disease duration of 2.2 ± 1.3 years. There was substantial agreement between the physician majority opinion about each case and the CRISS (κ = 0.76 [95% confidence interval (95% CI) 0.64-0.88]). The agreement between each individual physician opinion and the CRISS was also substantial (κ = 0.70 [95% CI 0.62-0.78]). All CRISS non-improvers were also rated as non-improved by physician majority; however, 12 CRISS improvers were rated as non-improved by physicians.

CONCLUSION

There was substantial agreement between the dichotomous CRISS rating and physician assessment of diffuse cutaneous SSc patients after 1 year. This supports the use of a CRISS cutoff at 0.6 for improvement versus non-improvement, although the CRISS tended to rate more patients as improved than did physicians.

A Narrative Review of Pathogenetic and Histopathologic Aspects, Epidemiology, Classification Systems, and Disease Outcome Measures in Systemic Sclerosis

Systemic sclerosis (SSc) is a rare systemic autoimmune disease, characterized by the presence of three main actors: vasculopathy, immune activation, and fibrosis. This pathologic process is then translated in a clinical picture with great variability among different patients in terms of type of organ involvement, disease severity and prognosis. This heterogeneity is a main feature of SSc, which, in addition to the presence of early phases of the disease characterized by mild symptoms, can explain the high difficulty in establishing classification criteria, and in defining patients' subsets and disease outcomes. The definition of disease outcomes is particularly relevant in the setting of clinical trials, where the aim is to provide reliable endpoints, able to measure the magnitude of the efficacy of a certain drug or intervention. For this reason, in the last years, increasing efforts have been done to design measures of disease activity, damage, severity, and response to treatment, often in the context of composite indexes. When considering disease outcomes, the experience of the patient represents a relevant and complementary aspect. The tools able to capture this experience, the patient-reported outcomes, have been increasingly used in the last years in clinical practice and in clinical trials, both as primary and secondary endpoints. This comprehensive narrative review on SSc will therefore cover pathogenetic and histopathologic aspects, epidemiology, classification systems, and disease outcome measures, in order to focus on issues that are relevant for clinical research and design of clinical trials.

Outcomes in patients with systemic sclerosis undergoing early versus delayed intervention with potential disease-modifying therapies

OBJECTIVE

To examine whether early therapeutic intervention, compared with delayed intervention, is beneficial for patients with early systemic sclerosis (SSc).

METHODS

This is a single-center, retrospective cohort study of SSc patients who received cyclophosphamide, mycophenolate mofetil, methotrexate, or tocilizumab for diffuse cutaneous SSc (dcSSc) or interstitial lung disease (ILD) within 6 years after disease onset. The patients were divided into early and delayed intervention groups based on the disease duration of ≤ 18 and >18 months at treatment introduction, respectively. Clinical worsening was defined as the development of any original or revised ACR Composite Response Index in Systemic Sclerosis (CRISS) step 1 event or progressive fibrosing ILD (PF-ILD).

RESULTS

There was no difference in baseline characteristics between the early (n = 25) and delayed (n = 21) intervention groups except forced vital capacity (FVC), which was better in the early vs delayed intervention groups. The early intervention group less frequently had stable pulmonary function over one year than did the late intervention group (odds ratio 0.087, 95% confidence interval 0.0079-0.51, p = 0.003). The active disease was significantly decreased from 79% to 42% in the early intervention group (p = 0.007), but the change in the delayed intervention group was not statistically significant (68% to 42%, p = 0.11). Cumulative rates free from clinical worsening events defined by revised ACR-CRISS and PF-ILD were significantly higher in the early vs delayed intervention groups (p = 0.03 and 0.003, respectively).

CONCLUSION

A therapeutic "window of opportunity" might exist in SSc patients.

Changes in skin score in early diffuse cutaneous systemic sclerosis are associated with changes in global disease severity

OBJECTIVE

To determine whether skin score changes are associated with changes in overall disease severity, function and quality of life in early dcSSc patients.

METHODS

A total of 154 and 128 dcSSc patients from the Canadian Scleroderma Research Group database with 1 and 2 year follow-up and a disease duration ⩽5 years without end-stage organ damage and/or significant comorbidity at the initial visit were included. Skin was assessed using the modified Rodnan skin score (mRSS) and disease severity by the summed Medsger disease severity score (DSS) (without skin domain), physician and patient global assessments, function [HAQ disability index (HAQ-DI)] and quality of life [36-item Short Form Health Survey (SF-36) physical component summary (PCS)]. Analyses were repeated in patients with a disease duration ⩽3 years.

RESULTS

At 2 years, 64 (50%) patients had improved skin (mRSS decrease of ⩾5 points and/or ⩾25%). Skin improvers had improved summed DSS (P = 0.002); better physician global assessments of disease activity, severity and damage (all P ⩽ 0.003); better HAQ-DI (P = 0.001) and SF-36 PCS (P = 0.005). Changes in the mRSS were positively correlated with changes in summed DSS (P = 0.006) and other disease outcomes. In the 26 (20.3%) patients with worsened skin (mRSS increase of ⩾5 points and/or ⩾25%), the summed DSS and physician global assessments were worse (P = 0.01 and P ⩽ 0.009, respectively). In the subgroup with a disease duration ⩽3 years, similar associations were found.

CONCLUSION

At 1 and 2 years, overall disease improvement parallels skin improvement in early dcSSc. This is important for prognosis and reflects the value of mRSS as an outcome measure in trials with these patients.

Less severe disease in patients with early systemic sclerosis?

Objectives: To evaluate the disease severity and activity in patients with a diagnosis of systemic sclerosis (SSc) after the 2013 American College of Rheumatology and the European League Against Rheumatism (ACR/EULAR) classification criteria development compared to patients diagnosed before 2013.Methods: One hundred and fifty-four subjects were included and assigned to the following groups: 120 SSc patients meeting the 1980 ACR criteria and with a diagnosis before 2013 (historical group), and 34 patients diagnosed after 2013, fulfilling the new ACR/EULAR criteria (early SSc group). Disease activity was assessed by the 2001 European Scleroderma Study Group Activity Index (EScSG-AI) and by the revised European Scleroderma Trials and Research group (EUSTAR) activity index. Disease severity was assessed using the Medsger Disease Severity Scale (DSS) and the summed DSS score.Results: The time between the first non-Raynaud's symptom and the diagnosis was shorter in early SSc than in the historical group (p = .001). The EScSG-AI and the EUSTAR activity index were similar between groups. The summed DSS score and the general, skin and gastrointestinal tract DSS scores were significantly lower in early SSc than in the historical group.Conclusion: SSc patients with a diagnosis after the new ACR/EULAR criteria development were diagnosed earlier and had a less severe disease than historical patients.

A normal diffusing capacity of the lungs for carbon monoxide is rare in incidental pulmonary arterial hypertension in systemic sclerosis: Data from the Pulmonary Hypertension Assessment and Recognition of Outcomes in Scleroderma cohort

Objective:

Our purpose was to determine the frequency of normal diffusing capacity for carbon monoxide defined as ⩾70% predicted, in those diagnosed with pulmonary arterial hypertension in the Pulmonary Hypertension Assessment and Recognition of Outcomes in Scleroderma cohort. We compared those with normal diffusing capacity for carbon monoxide to those with reduced diffusing capacity for carbon monoxide <70% in order to better clarify the role of pulmonary function testing as a screening test for pulmonary arterial hypertension and to better understand this population.

Methods:

Entry criteria included a right heart catheterization with mean pulmonary artery pressure ⩾25 mm Hg and pulmonary capillary wedge pressure ⩽15 mm Hg. Demographics, echocardiogram variables, B-type natriuretic peptide levels, right heart catheterization findings, and survival were described for both groups.

Results:

Of (n = 202), 11 (5.4%) had a diffusing capacity for carbon monoxide of ⩾70% versus 191 (94.6%) who had a diffusing capacity for carbon monoxide <70%. There were no identified statistical differences between the groups. Left atrium size was 4.1 cm in the normal diffusing capacity for carbon monoxide patients compared to 3.7 cm in the low diffusing capacity for carbon monoxide group but did not reach statistical significance. There were no statistically significant differences in survival. On repeat testing, seven patients subsequently developed a diffusing capacity for carbon monoxide <70%.

Conclusion:

Pulmonary Hypertension Assessment and Recognition of Outcomes in Scleroderma data suggest that it is very rare for a patient to develop pulmonary arterial hypertension with a preserved diffusing capacity for carbon monoxide. The data support the importance of obtaining diffusing capacity for carbon monoxide and that a patient with a normal diffusing capacity for carbon monoxide while suspected to have systemic sclerosis-pulmonary arterial hypertension should be considered critically. Diffusing capacity for carbon monoxide >70% was present in too few patients to find significant differences in B-type natriuretic peptide and atrium size. Future research should seek to confirm abnormal B-type natriuretic peptide, increased left atrium size, and other evidence of myocardial involvement on diffusing capacity for carbon monoxide.

The challenges and controversies of measuring disease activity in systemic sclerosis

Major alteration of the natural history of systemic sclerosis is limited with current treatments, and the development of novel therapies has been hampered, in part, by the lack of fully validated multi-system outcome measures. There remains a lack of consensus as to the very definition of systemic sclerosis disease activity, complicating efforts to measure activity in clinical trials. Previously published multi-system measures of disease status are yet to be fully validated according to the Outcome Measures in Rheumatology (OMERACT) filter. There is currently significant research interest in developing new systemic sclerosis-specific measures to better describe and compare patient cohorts and measure therapeutic responses in clinical trials. An accurate measure of disease activity in systemic sclerosis will facilitate the enrichment of clinical trials with patients who have active disease, targeting a group of patients most likely to benefit from therapeutic intervention. In addition, following on from successes in other rheumatic conditions, a state of low disease activity, measured by an activity index, may become a clinical trial end point and therapeutic target. The Scleroderma Clinical Trials Consortium has undertaken to develop a definition of disease activity and fully validate a new systemic sclerosis activity index. The Scleroderma Clinical Trials Consortium Activity Index will be developed using consensus and data-driven methods and is envisaged to be widely used in research and clinical settings.

The European Scleroderma Trials and Research group (EUSTAR) task force for the development of revised activity criteria for systemic sclerosis: derivation and validation of a preliminarily revised EUSTAR activity index

BACKGROUND

Validity of European Scleroderma Study Group (EScSG) activity indexes currently used to assess disease activity in systemic sclerosis (SSc) has been criticised.

METHODS

Three investigators assigned an activity score on a 0-10 scale for 97 clinical charts. The median score served as gold standard. Two other investigators labelled the disease as inactive/moderately active or active/very active. Univariate-multivariate linear regression analyses were used to define variables predicting the 'gold standard', their weight and derive an activity index. The cut-off point of the index best separating active/very active from inactive/moderately active disease was identified by a receiver-operating curve analysis. The index was validated on a second set of 60 charts assessed by three different investigators on a 0-10 scale and defined as inactive/moderately active or active/very active by other two investigators. One hundred and twenty-three were investigated for changes over time in the index and their relationships with those in the summed Medsger severity score (MSS).

RESULTS

A weighted 10-point activity index was identified and validated: Δ-skin=1.5 (Δ=patient assessed worsening during the previous month), modified Rodnan skin score (mRss) >18=1.5, digital ulcers=1.5, tendon friction rubs=2.25, C-reactive protein >1 mg/dL=2.25 and diffusing capacity of the lung for CO (DLCO) % predicted <70%=1.0. A cut-off ≥2.5 was found to identify patients with active disease. Changes in the index paralleled those of MSS (p=0.0001).

CONCLUSIONS

A preliminarily revised SSc activity index has been developed and validated, providing a valuable tool for clinical practice and observational studies.