Serum levels of proinflammatory cytokines are high in early childhood caries.

It is unknown whether serum levels of proinflammatory cytokines would be high in children with early childhood caries (ECC). This study investigated the association between serum levels of proinflammatory cytokines and severity of caries in preschoolers younger than 72 months. A case-control study was performed with a random sample of 72 children with ECC and 80 caries-free children. The explanatory variables were serum levels of proinflammatory cytokines (IL-6, TNF-α, and NGAL) and the outcome was severity of ECC (number of decayed teeth). Thecrudeanalyses were used toestimate the association between each cytokine and ECC. Then, the analyses were adjusted for socioeconomic factors, excess weight and sugar sweetened beverages consumption using Poisson regression models. The estimated coefficients were expressed as Means Ratio (MR), with 95% confidence intervals (CI). In the crude analyses, the highest tertiles of IL-6 (MR = 1.47, IC = 1.09-2.00, p = 0.012), TNF-α (MR = 1.33, CI = 1.00-1.78, p = 0.040) and NGAL (MR = 2.20, CI = 1.39-3.49, p = 0.001) were associated to ECC. After adjustment, the highest tertiles of IL-6 levels (MR = 1.54, IC = 1.13-2.10, p = 0.005), and NGAL (MR = 1.71, CI = 1.04-2.80, p = 0.032) remained associated to ECC; while TNF-α was no longer associated to ECC (MR = 1.31, CI = 0.98-1.75, p = 0.066). Higher serum levels of proinflammatory cytokines were associated to severity of caries in preschoolers, suggesting that chronic inflammation underlies ECC.