Almost one-fifth of patients with systemic lupus erythematosus developed Sjögren’s syndrome, which presented itself early in the disease progression, according to study results.
Researchers assessed 103 patients (90.3% women) with recent-onset systemic lupus erythematosus (SLE) for Sjögren’s syndrome (SS) based on American European Consensus Group criteria. Screening (European questionnaire, Schirmer-I test and water test), confirmation (fluorescein staining test, nonstimulated whole-salivary flow and anti-Ro/La antibodies) and lip biopsy were used. During cohort entry and SS assessment, anti-Ro/SSA and anti-La/SSB antibodies and rheumatoid factor were measured.
Mean age of patients at SLE diagnosis was 25.9 years; at study entry it was 30.9 years. Mean duration of SLE at study enrollment was 0.5 ± 0.3 years and 4 ± 1.9 years at SS assessment. Nineteen patients, all women, were diagnosed with SS.
“Patients were older at SLE diagnosis than patients without SS (P=.004),” researchers reported.
The patients with SLE and SS were more likely to have anti-Ro/SSA antibodies (84% vs. 55%; OR=4.3; 95% CI, 1.1-16.3). Being at least 25 years old and having anti-Ro/SSA antibodies at SLE diagnosis were predictors of SLE-SS, according to multivariate analysis. The absence of anti-Ro/SSA, anti-La/SSB and RF appeared to protect patients from SS (LR– 0.14; 95% CI, 0.02-0.95).
“SLE onset at age [25 years or older] plus the presence of anti-Ro/SSA antibody at diagnosis are useful predictors [of developing SS], while the absence of anti-Ro/SSA, anti-La/SSB and RF identifies patients at lowest risk,” the researchers concluded.