Clinical severity of atopic dermatitis is associated with dental caries risk in 3-year old children

Background: Infants with atopic dermatitis (AD) are reported to be at higher risk of early childhood caries (ECC) at 3-years, but the clinical validity of the reported link remains unknown. We investigated if clinical severity of AD in young children is associated with increased ECC risk at 3-years. Methods: In Growing Up in Singapore Towards healthy Outcomes (GUSTO) mother-offspring cohort, AD was diagnosed by trained physicians using Hanifin and Rajka criteria at 18-month and 3-year clinic visits (n=837). Of the children diagnosed with AD, disease severity was assessed using SCORAD (SCORing Atopic Dermatitis) index and categorized into moderate-to-severe AD (SCORAD≥25), and mild AD (SCORAD<25), with children without AD (non-AD) as a reference group. Oral examinations for ECC detection was performed by calibrated dentists in 656 children at age 3-years. Negative binomial regression was used to calculate the adjusted incidence risk ratio (aIRR; adjusted for socio-demographic factors and prenatal tobacco smoke exposure). Results: Atopic dermatitis was diagnosed in 7.3% (61/837) children; amongst which 23% had moderate-to-severe AD and 77% had mild AD. ECC was observed in 85.7%, 36.8% and 42.8% of the children in moderate-to-severe, mild and non-AD groups, respectively. Children with moderate-to-severe AD were at higher risk of ECC (aIRR 2.30 [95% confidence interval (CI) 1.04-5.06]; p=0.03) at 3 years compared to non-AD, while no association was seen between mild AD and ECC. Conclusions: Children with moderate-to-severe atopic dermatitis were at higher risk of ECC compared to those without AD and may benefit from early dental referral.