Fibromyalgia in Italian patients with primary Sjogren's syndrome

Objective. To assess the prevalence of fibromyalgia in primary Sjogren's syndrome and to evaluate the clinical differences between patients affected with both primary fibromyalgia and primary Sjogren's syndrome and those affected only with primary fibromyalgia. Methods. Clinical features of fibromyalgia were evaluated in 100 consecutive outpatients with primary Sjogren's syndrome and, as controls, in 90 patients with non-insulin-dependent diabetes mellitus, in 75 patients with primary fibromyalgia and in 30 healthy subjects. Results. Fibromyalgia was recorded in 22% of patients with primary Sjogren's syndrome, in 12.2% with diabetes and in 3.3% of healthy controls. In the primary Sjogren's syndrome group the prevalence was significantly higher than in healthy controls (P < 0.01), but not significantly different than in diabetes. Moreover, primary Sjogren's syndrome with fibromyalgia and primary fibromyalgia patients did not differ with respect to the number of tender points, while the mean pain threshold was lower in the latter (P = 0.05). Purpura, hypergammaglobulinemia, rheumatoid factor, and a focus score greater than or equal to 1 on lip biopsy were significantly more frequent in primary Sjogren's syndrome patients without than with fibromyalgia. Conclusions. As recently reported by other authors, our study confirms the moderate increase of fibromyalgia prevalence in primary Sjogren's syndrome. Typical fibromyalgic findings are quite similar to those of primary fibromyalgia, but surprisingly, primary Sjogren's syndrome patients with fibromyalgia show a less severe global involvement than those with primary Sjogren's syndrome alone. (C) 2002 Editions scientifiques et medicales Elsevier SAS.