Periodontitis and Non-alcoholic Fatty Liver Disease, a population-based cohort investigation in the Study of Health in Pomerania.

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) affects 20%-30% of adults with risk factors like obesity and insulin resistance putatively acting through chronic low-grade inflammation. Because periodontitis elicits low-grade inflammation, we hypothesized that it could contribute to NAFLD occurrence.

OBJECTIVE

To investigate epidemiologic associations between periodontitis and the incidence of NAFLD among 2,623 participants of the Study of Health in Pomerania.

METHODS

Periodontitis at baseline was defined as the percentage of sites (0%, <30%, ≥30%) with (i) clinical attachment level (CAL) ≥3 mm; (ii) probing pocket depth (PD) ≥4 mm. Incident NAFLD was defined as a significant increase in liver echogenicity on ultrasound relative to the kidneys, with the diaphragm indistinct or the echogenic walls of the portal veins invisible.

RESULTS

After a median 7.7 years of follow-up, 605 incident NAFLD cases occurred at a rate of 32.5 cases per 1,000 person-years. Relative to participants without CAL ≥3 mm, NAFLD incidence was elevated slightly in participants with <30% of sites affected and moderately in participants with ≥30% of sites affected (multivariable-adjusted incidence rate ratio = 1.28, 95% CI, 0.84, 1.95 and 1.60, 95% CI, 1.05-2.43), respectively. A similar dose-response relationship was not observed for PD.

CONCLUSION

History of periodontitis may be a risk factor for NAFLD.