Step forward in early recognition of systemic sclerosis: data from the Leiden CCISS cohort

BACKGROUND: Since 2009, Dutch patients with a confirmed diagnosis/suspicion of systemic sclerosis (SSc) can be referred to the Leiden Combined Care in Systemic Sclerosis (CCISS) cohort. This study evaluated whether early recognition of SSc has improved over time and whether disease characteristics and survival has changed over time. METHODS: 643 SSc patients fulfilling American College of Rheumatology/European Alliance of Associations for Rheumatology 2013 SSc criteria were included and categorised into three groups based on cohort-entry year: (1) 2010–2013 (n=229 (36%)), (2) 2014–2017 (n=207 (32%)) and (3) 2018–2021 (n=207 (32%)). Variables including disease duration, interstitial lung disease (ILD), digital ulcers (DU), diffuse cutaneous SSc (dcSSc), antitopoisomerase (ATA) and anticentromere (ACA) antibodies, and survival from disease onset were compared between cohort-entry groups, including analyses stratified for sex and autoantibodies. RESULTS: Over time, duration between onset of disease symptoms and cohort entry decreased in males and females, but was always longer in females than in males. The proportion of patients presenting with DU decreased, especially in ACA+SSc patients. Almost no ACA+ patients presented with ILD, while in ATA+ patients this proportion was 25% in 2010–2013 and decreased to 19% in 2018–2021. A reduction in patients presenting with clinically meaningful ILD and dcSSc was observed. Overall 8-year survival for males was 59% (95% CI 40% to 73%) and for females 89% (95% CI 82% to 93%). Eight-year survival showed a trend for improvement over time, and was always worse in males. CONCLUSION: We observed a decrease in disease duration in Leiden CCISS cohort at cohort entry, possibly indicating more timely diagnosis of SSc. This could provide opportunities for early interventions. While symptom duration at presentation is longer in females, mortality is consistently higher in males, underlining the urge for sex-specific treatment and follow-up.