WEDNESDAY, June 28, 2023 -- Systemic sclerosis (SSc) sine scleroderma (ssSSc) accounts for almost 10 percent of patients with SSc, according to a study published online June 28 in JAMA Dermatology.

Alain Lescoat, M.D., Ph.D., from the University of Rennes in France, and colleagues characterized the clinical phenotype of patients with ssSSc compared with patients with limited cutaneous SSc (lcSSc) and diffuse cutaneous SSc (dcSSc) in a study based on information from the international EUSTAR database.

Data were included for 4,263 patients with SSc; 376 (8.8 percent) were classified as having ssSSc. The researchers found that at the last available visit, patients with ssSSc had a lower prevalence of previous or current digital ulcers compared to the 708 patients with lcSSc and 708 patients with dcSSc (28.2 percent versus 53.1 and 68.3 percent, respectively) and lower prevalence of puffy fingers (63.8 percent versus 82.4 and 87.6 percent, respectively). The prevalence of interstitial lung disease was similar in ssSSc and lcSSc and was significantly higher in dcSSc (49.8 and 57.1 percent, respectively, versus 75.0 percent). In ssSSc, skin telangiectasias were associated with diastolic dysfunction (odds ratio, 4.778). Positivity for anti-Scl-70 antibodies was the only independent factor for the onset of skin fibrosis in ssSSc (odds ratio, 3.078). After up to 15 years of follow-up, the survival rate was higher in patients with ssSSc versus lcSSc and dcSSc (92.4 percent versus 69.4 and 55.5 percent, respectively).

"The positivity for anti-Scl-70 was the only independent parameters associated with the onset of skin fibrosis in ssSSc, strengthening the relevance of antibody subtypes to predict the trajectory of skin involvement in patients with SSc," the authors write.

Several authors disclosed ties to the biopharmaceutical industry.