Increased frequency of Sjögren's syndrome in patients with spondyloarthropathy.

Objective: To determine the prevalence of sicca symptoms and Sjögren's syndrome (SS) in spondyloarthropathy (SpA) patients with ankylosing spondylitis (AS) and undifferentiated SpA (uSpA).
Methods: Patients with SpA with inflammatory back pain and/or peripheral arthritis presenting to the university outpatient clinic were diagnosed as AS (n = 40) and uSpA (n = 65) according to established criteria. Patients with SpA with sicca symptoms and/or positive antinuclear antibody (ANA) were investigated for SS by minor salivary gland biopsy and/or sialography. To assess sicca symptoms in this cohort systematically we mailed a validated questionnaire with 6 questions on dryness of eyes and mouth to all 105 SpA patients and 150 healthy controls, a positive answer to > or = 3 questions was taken as suggestive of SS. There was no significant difference in baseline characteristics between patients and controls.
Results: In 8/105 SpA patients (5 uSpA, 3 AS; 6 female, 2 male) SS diagnosis by the European criteria indicated a frequency of 7.6%. Of 105 SpA patients, 12 were ANA+ (11.4%), of whom 7 had SS; thus, ANA were detected in 7/8 SpA patients with SS (88%). Of the 84 SpA patients responding to the questionnaire (80%), 10 gave a positive answer to > or = 3 questions (11.9%) compared to 2 of 131 (1.5%) controls (87.3%) (odds ratio = 8.7, 95% CI 2.3-32.5, p < 0.01).
Conclusion: The data suggest increased prevalence of sicca symptoms and SS in SpA patients with AS and uSpA. The occurrence of a secondary SS in a variety of inflammatory diseases suggests that salivary gland involvement in these conditions results from as yet unidentified shared pathogenic mechanisms resulting in nonspecific inflammation in this location.