Periodontitis is associated with significant hepatic fibrosis in patients with non-alcoholic fatty liver disease

Background and aims: Non-alcoholic fatty liver disease (NAFLD) has a bidirectional association with metabolic syndrome. It affects up to 30% of the general population, 70% of individuals with diabetes and90% with obesity. The main histological hallmark of progressive NAFLD is fibrosis. There isa bidirectional epidemiological link between periodontitis and metabolic syndrome. NAFLD,periodontitis and diabetes share common risk factors, are characterised by inflammation and associated with changes in commensal bacteria. Therefore we tested the hypothesisthat periodontitis is associated with NAFLD and with significant fibrosis in two study groups. Methods: We analyzed data from a population-based survey and a patient-based study. NHANES IIIparticipants with abdominal ultrasound and sociodemographic, clinical, and oral examination data were extracted and appropriate weighting applied. In a separate patient-basedstudy, consenting patients with biopsy-proved NAFLD (or with liver indices too mild to justifybiopsy) underwent dental examination. Basic Periodontal Examination score was recorded.Results: In NHANES, periodontitis was significantly associated with steatosis in 8172 adults evenafter adjusting for sociodemographic factors. However, associations were fully explainedafter accounting for features of metabolic syndrome. In the patient-based study, periodontitis was significantly more common in patients with biopsy-proven NASH and any fibrosis(F0-F4) than without NASH (p = 0.009). Periodontitis was more common in patients with NASH and significant fibrosis (F2-4) than mild or no fibrosis (F0-1, p = 0.04).Conclusions: Complementary evidence from an epidemiological survey and a clinical study show that NAFLD is associated with periodontitis and that the association is stronger with significantliver fibrosis