Sex differences in the association between dual‐energy x‐ray absorptiometry‐measured body composition and periodontitis

Abstract Background A positive association between obesity based on body mass index (BMI) and periodontitis has been reported. Fat tissue‐related systemic inflammation acts as the link to periodontal comorbidities of obesity. However, the BMI is unable to distinguish fat and fat‐free tissues. More precise measures are required to evaluate body composition, including fat and fat‐free tissues. This study aimed to determine the sex differences in the association between dual‐energy x‐ray absorptiometry (DXA)‐measured body composition (i.e., fat mass and muscle mass) and phenotypes with periodontitis. Methods Cross‐sectional data of 3892 participants from the National Health and Nutrition Examination Survey (NHANES) study 2011‒2014 were analyzed. Adiposity indices (fat mass index [FMI] and percentage body fat [%BF]) and muscle mass index (MMI) were calculated. The participants were categorized by the quintiles of FMI, MMI, and %BF. Body composition phenotypes were categorized as: low adiposity‐low muscle (LA‐LM), low adiposity‐high muscle (LA‐HM), high adiposity‐low muscle (HA‐LM), or high adiposity‐high muscle (HA‐HM), respectively. Periodontitis was defined by the CDC/AAP (Centers for Disease Control and Prevention/American Academy of Periodontology) criteria. Multivariable logistic regression analysis was conducted, stratified by sex. We further adjusted for white blood cell (WBC) counts in the sensitivity analysis. Results Restricted cubic splines revealed non‐linear associations between body composition indices and periodontitis risk. Women with a higher FMI (odds ratio for Q5 vs. Q1 [OR Q5vs1 ] = 1.787, 95% confidence interval: 1.209–2.640) or %BF (OR Q5vs1 = 2.221, 1.509–3.268) had increased odds of periodontitis. In addition, women with HA‐LM phenotype were more likely to develop periodontitis (OR = 1.528, 1.037–2.252). Interestingly, the WBC count, a systemic inflammatory biomarker, attenuated these associations. No statistically significant associations were found in men. Conclusions The association between DXA‐measured body composition and phenotypes with periodontitis differs per sex. Only in women higher adiposity indices and HA‐LM phenotype were associated with an increased risk of periodontitis.