Sjögren’s syndrome found in one-fifth of lupus patients
medwireNews: Researchers have identified key characteristics that predict the development of Sjögren's syndrome (SS) in patients with systemic lupus erythematosus (SLE), finding that up to a fifth of patients are affected.
The team found that patients were most likely to develop SS early in the course of SLE, with older patients and those positive for anti-Ro/SSA antibodies at greatest risk for the diagnosis. Patients without anti-Ro/SSA and anti-La/SSB antibodies or rheumatoid factor (RF) are the least likely to develop SS, add Jorge Sánchez-Guerrero (University of Toronto, Ontario, Canada) and co-authors.
The study included 103 patients (93 of whom were women) with recent-onset SLE who completed a screening questionnaire for SS, followed by confirmation tests, including measurement of non-stimulated whole-salivary flow, antinuclear autoantibodies, and lip biopsy.
The patients were aged an average of 25.9 years at SLE diagnosis and patients had been diagnosed with SLE a mean of 4.0 years before SS testing.
Overall, 18.5% of patients tested positive for SS, all of whom were women. The patients with SS were older than those without, at 30.8 versus 24.0 years old, the team reports in Rheumatology. Those with SLE plus SS were also significant more likely to carry the anti-Ro/SSA antibody than patients with SLE alone (84.2 vs 55.0%).
Indeed, after adjusting for gender, the likelihood of SS diagnosis was greater with for patients aged 25 years or older (odds ratio [OR]=3.8) and positive for anti-Ro/SSA antibodies (OR=4.4), whereas absence of anti-Ro/SSA, anti-La/SSB, and RF were protective against the diagnosis.
"Based on our results, we may conclude that an overlap of SLE and SS occurs in almost one-fifth of SLE patients and the overlap is early rather than late," Sánchez-Guerrero et al conclude.
"SLE onset at age ≥25 years plus the presence of anti-Ro/SSA antibody at diagnosis increases this probability."
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Lynda Williams, Senior medwireNews Reporter