CNS Involvement in Primary Sjogren Syndrome: Assessment of Gray and White Matter Changes With MRI and Voxel-Based Morphometry

OBJECTIVE. The purpose of this study was to evaluate with MRI the involvement of gray matter and white matter structures in patients with primary Sjogren syndrome. SUBJECTS AND METHODS. Fifty-three patients with primary Sjogren syndrome, 18 age-and disease duration-matched patients with systemic sclerosis, and 35 age-matched control subjects were examined for differences in white matter hyperintensities (WMHIs) detected on FLAIR MR images. Differences in brain volume between patients with primary Sjogren syndrome and controls were studied by application of voxel-based morphometry to a 3D T1-weighted sequence. RESULTS. WMHIs were observed in 38 of the 53 patients with primary Sjogren syndrome, six of 18 patients with systemic sclerosis, and 17 of 35 controls. The numbers of WMHIs 2 mm or larger and the number smaller than 2 mm were higher in patients with primary Sjogren syndrome than in controls (>= 2 mm, p = 0.004; < 2 mm, p < 0.001). No significant difference was observed in the number of WMHIs in primary Sjogren syndrome patients and that in systemic sclerosis patients. After control for age, a positive relation was found between disease duration and total number of WMHIs (p = 0.037) and number of WMHIs 2 mm or larger (p = 0.023) in patients with primary Sjogren syndrome. In comparison with the controls, patients with primary Sjogren syndrome had decreased gray matter volume in the cortex, deep gray matter, and cerebellum. Associated loss of white matter volume was observed in areas corresponding to gray matter atrophy and in the corpus callosum (p < 0.05). CONCLUSION. Patients with primary Sjogren syndrome have WMHIs and gray and white matter atrophy, probably related to cerebral vasculitis.