Epidemiological profile and north–south gradient driving baseline systemic involvement of primary Sjögren’s syndrome

Abstract Objective To characterize the systemic phenotype of primary Sjögren’s syndrome at diagnosis by analysing the EULAR-SS disease activity index (ESSDAI) scores. Methods The Sjögren Big Data Consortium is an international, multicentre registry based on worldwide data-sharing cooperative merging of pre-existing databases from leading centres in clinical research in Sjögren’s syndrome from the five continents. Results The cohort included 10 007 patients (9352 female, mean 53 years) with recorded ESSDAI scores available. At diagnosis, the mean total ESSDAI score was 6.1; 81.8% of patients had systemic activity (ESSDAI score ≥1). Males had a higher mean ESSDAI (8.1 vs 6.0, P