Systemic sclerosis overlap and non-overlap syndromes share clinical characteristics but differ in prognosis and treatments

To screen for concomitant autoimmune disease in patients with systemic sclerosis (overlap SSc) and to describe their clinical characteristics prognosis. This was a two-center retrospective observational study. Patients diagnosed SSc according the 2013 ACR-EULAR scleroderma classification criteria were screened rheumatoid arthritis (RA), Sjögren syndrome (SgS) lupus erythematosus (SLE). Patient retrieved from medical records compared those of non-overlap cohort. Among 534 studied, thirty-four (6.4%) identified as having overlap SSc. There 21 (3.9%) RA, 14 (2.6%) SgS 4 (0.7%) SLE (5 had 2 AISD) . The phenotype similar that terms cutaneous phenotype, prevalence pulmonary arterial hypertension, interstitial lung disease, digital ulcers mortality. Using multivariate Cox model, age (HR = 1.04, 95% CI [1.02–1.07]), modified Rodnan skin score 1.08 per point, [1.05–1.11]), presence 3.79, [1.38–10.40]) significantly associated Overlap more likely receive corticosteroids (85.3% vs. 45%, p < 0.001), immunosuppressive drugs (82.4% 49.2%, 0.001) biologics (52.9% 3.8%, ZZ0.001). While shared common characteristics, SgS/SSc higher risk mortality, RA/SSc received corticosteroids, methotrexate biologics. Screening an AISD should be promoted since co-occurrence may affect prognosis treatments.