Introduction: While poor oral hygiene has been previously associated with an increased risk of non-alcoholic fatty liver disease (NAFLD), its association with hepatic fibrosis remains unclear. Here, we sought to analyze if toothbrushing frequency, an easy-to-assess indicator of oral health habits, would be associated with liver stiffness measurement (LSM) by transient elastography (TE) in patients with an established diagnosis of NAFLD.
Methods: In this registry-based study, LSM was measured in 1156 patients with NAFLD and analyzed in relation to the self-reported daily frequency of toothbrushing. LSM values ≥12 kPa were considered as indicative of cirrhosis.
Results: A trend towards a stepwise decrease (cross-sectional p = 0.13) in LSM was found in patients who reported having their teeth brushed more frequently: less than once a day (10.6 ± 8.6 kPa; 13% of the study sample), once a day (9.95 ± 8.40 kPa; 40%), twice a day (9.21 ± 7.63 kPa; 43%), and after every meal (8.91 ± 5.30 kPa; 4%). Patients who brushed their teeth less than once a day had a significantly higher prevalence of LSM values ≥12 kPa (p < 0.05). In multivariable logistic regression analysis, the association of LSM values ≥ 12 kPa with toothbrushing habits remained statistically significant for less than once a day (odds ratio = 1.69, 95% confidence interval = 1.07-2.66, p = 0.02) with reference to twice a day or after every meal.
Conclusion: Among patients with NAFLD, there is an independent association between brushing teeth less than once a day and TE-established cirrhosis.