Adiposity and gingival crevicular fluid tumour necrosis factor-alpha levels in children.
To investigate whether adiposity is associated with gingival crevicular fluid (GCF) tumour necrosis factor-alpha (TNF-alpha) levels in children. We also examined whether this relationship is mediated through plasma fasting insulin. This preliminary study used cross-sectional data from the baseline-visit of the Quebec Adipose and Lifestyle InvesTigation in Youth cohort, which is an ongoing longitudinal study investigating the natural history of obesity in Quebec children. Study participants (76 girls and 102 boys) include children aged 8-10 years and their families, living in the Montreal and Quebec City areas. TNF-alpha level was measured in pooled samples (N=4) for each child by enzyme-linked immunosorbant assay. Height and weight were measured. Body mass index (BMI) was calculated as weight/height(2) (kg/m(2)). Sex/age-specific BMI was categorized into normal (<85th percentile), overweight (85th-95th percentile) and obese (>or=95th percentile) defined by the 2000 US-CDC growth charts. Insulin resistance was measured using fasting plasma insulin in children. Data analysis involved descriptive and multiple linear regression analyses. Our results suggest that obesity in boys was associated with a 37% increase of GCF-TNF-alpha level. However, when accounting for insulin resistance this association was reduced and disappeared while the model's goodness of fit improved. These findings provide support for the link between adiposity in children and GCF-TNF-alpha level, which appears to be mediated by insulin resistance.