Objectives To analyse the epidemiological, clinical and immunological characteristics of an international cohort of patients diagnosed with primary Sjögren syndrome (SS) according to the 2002 AE criteria.
Methods The Big Data Sjögren Project is an international, multicentre registry formed in 2014 to take a “high-definition” picture of the main features of primary SS at diagnosis by merging international SS databases. By January 2015, 5027 consecutive patients fulfilling the 2002 classification criteria for primary SS were included from 9 European and 4 American countries.
Results The cohort included 4714 (94%) women (female:male ratio, 15:1), with a mean age at diagnosis of primary SS of 54 years (range, 10-97), of which 94% were Caucasian and 88% lived in European countries. The frequency of fulfilment of the 2002 criteria was: 94.4% for dry eye, 92.9% for dry mouth, 88.5% for positive salivary gland biopsy, 85.9% for positive ocular tests, 74.8% for positive oral tests and 70.9% for positive Ro/La autoantibodies. As a minimum of 4 of the 6 criteria are required for fulfilment, the percentage of diagnostic tests performed varied: Ro/La autoantibodies were tested in 99.5% of patients, ocular diagnostic tests (Schirmer's test and/or corneal stainings) were made in 90.2%, oral tests in 76.7% and salivary gland biopsy in 72% of patients. Systemic involvement at diagnosis was retrospectively measured using ESSDAI definitions in 3314 patients and included articular involvement (35.2%), glandular involvement (19.3%), lymphadenopathy (10.7%), cutaneous involvement (9%), constitutional involvement (8.4%), respiratory involvement (7.3%), peripheral nervous system involvement (5.2%), renal involvement (2.2%), central nervous system involvement (1.7%) and muscular involvement (1.2%). With respect to laboratory abnormalities, 43.3% of patients showed biological abnormalities and 24.7% haematological abnormalities according to ESSDAI definitions.
Conclusions In this international cohort of 5027 patients with primary SS, most non-sicca clinical features and laboratory abnormalities present at diagnosis are not included in the current criteria; their inclusion in future proposed classification criteria should be evaluated.
Disclosure of Interest None declared