Periodontitis in patients with primary Sjögren's syndrome: A nation-wide register study.

The aim of this study was to compare the occurrence of periodontitis in patients with primary Sjögren's syndrome (pSS) and a non-Sjögren's patient group during a 7-year period from 2011 through 2017. In this population-based study, the patients were identified based on the International Classification of Diseases-10 (ICD-10) codes registered in the Norwegian Patient Registry (NPR), which contains information on diagnosis and time of admission for all hospitalized patients in Norway. The pSS group comprised patients with ≥4 registrations with ICD-10 code M35.0 (Sjögren's syndrome) as the main diagnosis. The dependent variable was periodontitis, defined by procedure codes registered in the Norwegian Control and Payment of Health Reimbursement (KUHR). Logistic regression analyses estimated the odds ratio for periodontitis in pSS patients relative to non-pSS patients, adjusted for relevant covariates. Lastly, regression analyses were performed separately for each of the 6 age categories. In total, 760 (7.5%) patients in the pSS group and 22,178 (7.1%) in the non-pSS group had periodontitis. When adjusting for covariates, the presence of pSS had no association with periodontitis (OR = 1.06, 95% CI: 0.98-1.14).