Registry of the Spanish network for systemic sclerosis: clinical pattern according to cutaneous subsets and immunological status.

OBJECTIVE

To investigate the incidence of clinical and immunological characteristics of a large cohort of Spanish patients with scleroderma (SSc) and identifying factors associated with particular organ manifestations assessed by a nationwide cross-sectional analysis.

METHODS

We classified SSc patients in 4 subsets using a modification of LeRoy and Medsger classification that included: "prescleroderma" (pre-SSc), limited cutaneous SSc (lcSSc), diffuse cutaneous SSc (dcSSc), and SSc sine scleroderma (ssSSc). Fourteen Spanish centers participated in patient recruitment. On January 2008, the database included 916 consecutive Spanish SSc patients, 801 women (87.4%) and 115 men (12.6%), all of whom fulfilled the classification criteria proposed by LeRoy and Medsger. Epidemiological, clinical, and laboratory data were collected according to a standard protocol. Mean age at diagnosis was 51.2 ± 15.1 years and mean age at disease onset was 44.9.0 ± 15.8 years. lcSSc was the most frequent subset (61.8%) followed by dcSSc (26.5%), ssSSc (7.5%), and preSSc (4%) subsets. Gender ratios were as follows: dcSSc subset, 200 women and 43 men (4.7:1); lcSSc subset, 503 women and 63 men (ratio 7.9:1), and ssSSc subset, 62 women and 7 men (ratio 8.9:1). Digital ulcers, interstitial lung disease (ILD), musculoeskeletal and esophageal involvement, and scleroderma renal crisis were more frequent in dcSSc than lcSSc and ssSSc subsets. The incidence of pulmonary arterial hypertension assessed by echocardiography was similar in all subsets but mean estimated systolic pulmonary arterial pressure was higher in ssSSc than in lcSSc subset (47.3 ± 23.9 mm Hg vs 39.6 ± 19.2 mm Hg; P < 0.03). Cardiac involvement was identified more frequently in ssSSc than in dcSSc and lcSSc subsets (49.3% vs 32.5% and 31.1%, respectively; P = 0.015 and P = 0.004 for both comparisons). Acro-osteolysis (8.2% vs 2.4%, P = 0.049), calcinosis (19.8% vs 7.2%, P < 0.05), and sicca syndrome (37.5% vs 14.5%, P < 0.0001) were more frequent in lcSSc than in ssSSc subsets. The frequency of clinical manifestations related to the presence of anticentromere antibodies or antitopoisomerase I antibodies was very similar to that identified in patients categorized to lcSSc and dcSSc, respectively. However, in multivariate studies, the ranking of the variables according to their overall explanatory effect on the model showed that the contributory effect of the antibody status was not greater than that of the clinical categorization into lcSSc and dcSSc for the majority of disease manifestations, but, in important manifestations, as ILD, absence of anticentromere antibodies was an independent predictor factor.

CONCLUSIONS

The classification of SSc into dcSSc, lcSSc, and ssSSc subsets is the one that most closely reflects the natural history of the disease, as they presented clear clinical differences. The immunological profile helps to define important visceral alteration as ILD. Finally, to improve early diagnosis of SSc, patients with preSSc should be considered both to trace the true evolution of the disease and to define which patients could benefit from therapeutic measures able to prevent the appearance of visceral involvements.