Increased bronchial responsiveness in primary and secondary Sj?gren's syndrome

We examined one group of 33 patients with primary Sj?gren's syndrome, one group of 17 patients with secondary Sj?gren's syndrome, i.e. associated with other connective tissue diseases, and one group of 14 patients with connective tissue diseases but without Sj?gren's syndrome. In each patient we obtained chest radiographs and measured lung volumes, carbon monoxide diffusing capacity and airway responsiveness to methacholine. We observed no difference in chest radiograph abnormalities, in lung volumes and in carbon monoxide diffusing capacity among the three groups. However, we found a slight but significant increase of bronchial responsiveness in patients with primary and secondary Sj?gren's syndrome compared with patients with connective tissue disorders but without Sj?gren's syndrome. Thus PD20FEV1 methacholine was 1.07 mg (1.2) (geometric mean and GSEM) in primary Sj?gren's syndrome, 0.91 mg (1.4) in secondary Sj?gren's syndrome (NS), and 2.24 mg (1.09) in patients with connective tissue diseases but without Sj?gren's syndrome (t = 2.59 and t = 2.8, both p less than 0.05, vs primary and secondary Sj?gren's syndrome, respectively). These results show that some patients with Sj?gren's syndrome have mild bronchial hyperresponsiveness, which may be related to the specific airway abnormalities of this disease.