LAUSR

Background: Pulmonary hypertension (PH) is a life-threatening complication of systemic sclerosis (SSc), thought to be more commonly found in limited cutaneous (lcSSc) compared to diffuse (dcSSc) subset. Since lcSSc has a better prognosis, it is unclear whether a higher occurrence of PH in lcSSc reflects survival bias. Objectives: To compare the cumulative PH incidence in disease subsets, after accounting for death as a competing event, in a large multi-center SSc cohort. Methods: Cumulative incidence of PH was studied in 1431 Canadian Scleroderma Research Group (CSRG) database patients (57% lcSSc; follow-up 3.5±2.9 years, range 1-14) by Fine-Gray analysis, unadjusted and adjusted for sex, age and SSc-related autoantibodies (SAS 9.4). Survival curves, predictors of PH development and survival were analyzed by Kaplan-Meier and Cox proportional hazards analyses (SPSS 25.0). Subgroup analysis was performed for PAH. Results: 157 SSc patients had PH (including 117 PAH), either confirmed by RHC or postmortem. Compared to those without PH, lcSSc-PH patients had longer disease and older age at SSc diagnosis, while dcSSc-PH patients - more severe peripheral vascular and gastrointestinal involvement. The cumulative incidences of PH/PAH were similar in dcSSc and lcSSc after accounting for death in the adjusted competitive risk model (Table 1; Fig.1). 47% of PH- and 42% of PAH-patients died over a FU period. Male gender (p Conclusion: Cumulative incidence of PH, after accounting for death as competing event, was comparable in SSc subsets. Vigilance should be considered in males, Scl-70 positive and late age-onset SSc. Disclosure of Interests: Tatiana Nevskaya: None declared, Yuxuan Jiang: None declared, Mianbo Wang: None declared, Murray Baron: None declared, Janet Pope Grant/research support from: AbbVie, Bristol-Myers Squibb, Eli Lilly & Company, Merck, Roche, Seattle Genetics, UCB, Consultant of: AbbVie, Actelion, Amgen, Bayer, Boehringer Ingelheim, Bristol-Myers Squibb, Eicos Sciences, Eli Lilly & Company, Emerald, Gilead Sciences, Inc., Janssen, Merck, Novartis, Pfizer, Roche, Sandoz, Sanofi, UCB, Speakers bureau: UCB