PPARγ gene polymorphism, C‐reactive protein level, BMI and periodontitis in post‐menopausal Japanese women

Abstract

Several studies have reported inconsistent results regarding the association between the PPARγPro12Ala polymorphism and obesity. Obese individuals had higher C-reactive protein (CRP) levels compared with those of normal weight, and PPARγ activation could significantly reduce serum high-sensitive CRP level. We have previously suggested that the Pro12Ala polymorphism represents a susceptibility factor for periodontitis, which is a known risk factor for increased CRP level. The aim was to investigate associations between PPARγ gene polymorphism, serum CRP level, BMI and/or periodontitis among post-menopausal Japanese women. The final sample in this study comprised 359 post-menopausal Japanese women. Periodontal parameters, including PD, CAL and BOP, were measured per tooth. PPARγPro12Ala genotype was determined by PCR-RFLP. Hs-CRP value was measured by a latex nephelometry assay. No significant differences in age, BMI or periodontal parameters were found between the genotypes. The percentages of sites with PD≥4mm were significantly higher among the hsCRP≥1mg/l group than the hsCRP<1mg/l group (p=0.003). Positive correlations were found between serum hsCRP levels and the percentages of sites with PD≥4mm (p=0.043) in PPARγ Ala allele carriers, and BMI (p=0.033) in non-carriers. After adjustment for model covariates, BMI was significantly associated with serum hsCRP level. The PPARγPro12Ala polymorphism was not independently associated with periodontitis, serum CRP level or BMI in post-menopausal Japanese women. However, serum hsCRP level correlated with periodontitis in Ala allele carriers, and with BMI in non-carriers.