RESUMEN
BACKGROUND: Associations between periodontitis and cardiovascular and autoimmune diseases are most often assessed in patients with a particular cardiovascular or autoimmune disease. To prevent selection bias, this study assesses the existence of associations between periodontitis and cardiovascular and autoimmune diseases in patients attending a dental or periodontal clinic. METHODS: Data were collected from 1,276 randomly selected dental records from patients attending a dental (n = 588) or periodontal (n = 688) clinic. Data on the prevalence of cardiovascular and autoimmune diseases were obtained from a validated health questionnaire. Data on the presence of periodontitis were taken from patients' dental records. RESULTS: In uncontrolled analyses, the prevalence of hypertension, diabetes mellitus (DM), and rheumatoid arthritis (RA) is significantly increased in patients with periodontitis. Controlled for confounding, periodontitis was associated with DM, with an odds ratio of 4 (1.03 to 15.3), in the dental clinic. DM was not associated with periodontitis in periodontal clinics. Hypertension does not seem to be associated with periodontitis when controlling for confounders. Periodontitis may be associated with RA in both clinic types. CONCLUSIONS: The increased prevalence of cardiovascular and autoimmune diseases among patients with periodontitis attending dental or periodontal clinics may, at least in part, be influenced by confounding. However, the increased prevalence of DM and RA in patients with periodontitis could not be explained by confounding.