Comprehensive description of the prevalence, serological and clinical characteristics, and visceral involvement of systemic sclerosis (scleroderma) in a large cohort from the United Arab Emirates Systemic Sclerosis Registry

Abstract

Systemic sclerosis is an autoimmune condition characterized by a wide range of clinical presentations. Registries may serve to expand understanding about systemic sclerosis and aid in patient care and follow-up. The objective of this study was to analyze the prevalence of systemic sclerosis in a large cohort from the United Arab Emirates Systemic Sclerosis Registry and find the significant similarities and differences between the different subsets. All scleroderma patients in the United Arab Emirates were included in this multicenter national retrospective analysis. Data on demographics, comorbidities, serological characteristics, clinical aspects, and treatment were collected and analyzed, highlighting the most common traits identified. A total of 167 systemic scleroderma patients from diverse ethnic backgrounds were enrolled. Overall, 54.5% (91/167) of the patients were diagnosed with diffuse cutaneous systemic sclerosis, and 45.5% (76/167) with limited cutaneous systemic sclerosis. The prevalence of systemic sclerosis was 1.66 per 100,000 for the total registry and 7.78 per 100,000 for United Arab Emirates patients. Almost all patients in the diffuse cutaneous systemic sclerosis and limited cutaneous systemic sclerosis groups tested positive for the immunofluorescence antinuclear antibody. Antibodies against Scl-70 were significantly more associated with diffuse cutaneous systemic sclerosis, whereas anticentromere antibodies were significantly more associated with the limited cutaneous systemic sclerosis group (p < 0.001). Sclerodactyly, shortness of breath, and digital ulcers were more common in diffuse cutaneous systemic sclerosis patients compared with the limited cutaneous systemic sclerosis subtype in terms of clinical symptoms and organ involvement. Telangiectasia was much more common in the limited cutaneous systemic sclerosis group. Furthermore, diffuse cutaneous systemic sclerosis patients had more lung fibrosis (interstitial lung disease) than limited cutaneous systemic sclerosis patients (70.5% vs 45.7%), and pulmonary arterial hypertension was twice as common in limited cutaneous systemic sclerosis patients as it was in diffuse cutaneous systemic sclerosis patients. Local registries are paramount to understanding the clinical/serological characteristics of scleroderma. This study emphasizes the importance of raising disease awareness and distinguishing between the various systemic sclerosis subsets to implement patient-tailored strategies for early detection, better management, and higher quality of care.

Keywords: Cohort; United Arab Emirates; diffuse cutaneous systemic sclerosis; limited cutaneous systemic sclerosis; prevalence; scleroderma; systemic sclerosis.

Figure 1.

Representation of the clinical manifestations of scleroderma for (a) the Whole registry and (b) Emirati patients (to the right favors lcSSc, to the left favors dcSSc).