Periodontitis affects glucoregulatory hormones in severely obese individuals

To evaluate the effect of periodontitis (PD) on glucoregulatory hormones in obesity, never explored so far, a cross-sectional study was conducted in 110 severely obese, non-diabetic individuals. We collected clinical periodontal parameters, including probing pocket depth (PPD), bleeding on probing (BOP), clinical attachment level (CAL). Insulin, glucagon, GLP-1 and GIP were measured after 3 days of standardized diet. Forty-seven subjects had periodontitis (PD+) and 63 did not (PD−). PD+ showed 30.3% of gingival sites with PPD > 4 mm, 55.2% of BOP sites and a mean CAL loss of 4.1 mm. Compared with PD−, PD+ had higher glucagon (26.60 [25.22] vs 3.93 [7.50] ng/l, p < 0.0001) and GIP levels (10.56 [13.30] vs 6.43 [8.43] pmol/l, p < 0.001), while GLP-1 was reduced (11.78 [10.07] vs 23.34 [16.80] pmol/l, p < 0.0001). Insulin did not differ. In PD+, after adjustment for confounders, PPD was positively related to glucagon (β = 0.424, p = 0.002) and inversely to GLP-1 (β = −0.159, p = 0.044). We describe for the first time an impaired incretin axis coupled with a relative hyperglucagonemia in obese non-diabetic individuals with PD, that might contribute to deteriorate their glucose tolerance and partially explain the higher risk of diabetes observed in these patients.