Characteristics of ScleroID highlighting musculoskeletal and internal organ implications in patients afflicted with systemic sclerosis

BACKGROUND: Systemic sclerosis (SSc) is a multi-organ disease with impaired health-related quality of life (HRQoL). The EULAR SSc Impact of Disease (ScleroID) is a newly introduced SSc-specific patient-reported outcome to evaluate HRQoL in SSc. OBJECTIVE: To investigate the correlation between the ScleroID and the involvement of organ systems as well as disease activity/damage in a SSc cohort from a large tertiary care centre. PATIENTS AND METHODS: The ScleroID and clinical characteristics including internal organ involvement and hand function were investigated in 160 consecutive patients with SSc (median age 46 (43;56) years; diffuse cutaneous SSc 55%). RESULTS: A strong correlation was found between the ScleroID and articular disease activity scores (DAS28-CRP, DAS28-ESR, CDAI, SDAI), a hand function performance test, the Hand Anatomy Index and muscle strength tests. Additionally, a strong significant correlation was discovered using instruments representing hand function and musculoskeletal disability including the Cochin Hand Function Scale, the Quick Questionnaire of the Disability of the Hands, Arms and the Shoulders and the Health Assessment Questionnaire Disability Index. A significant negative correlation was found between the ScleroID score and the 6-min walking test (6MWT) (rho − 0.444, p < 0.001). Clinically mild lung/heart disease did not show increased ScleroID values. The Mouth Handicap in the Scleroderma Scale and the University of California Los Angeles Scleroderma Clinical Trials Consortium gastrointestinal tract 2.0 also showed significant positive correlations to the ScleroID score (rho: 0.626, p < 0.001; rho: 0.646, p < 0.001, respectively). Patients experiencing oesophageal difficulties bore a significantly higher score compared to individuals with a normal functioning oesophagus (3.2/1.5;4.5/ vs. 2.2/1.0;3.2/, p = 0.011). Moreover, the ScleroID showed a significant positive correlation to the revised EUSTAR disease activity index and modified activity index. CONCLUSION: In a large single-centre cohort, the previously described ScleroID-related findings were confirmed. Furthermore, several organ involvement-related functional and performance tests showed a good correlation to the ScleroID including the 6MWT and gastrointestinal-related complaints. Many aspects of musculoskeletal damage, overall disease activity, pain and fatigue were also well represented in the ScleroID, which efficiently reflects the impact of organ involvement, disease activity and functional damage.