Pregnancy and childhood exposure to residential traffic noise and overweight at 7 years of age

Background: Exposure to road traffic noise has been associated with adiposity and diabetes in adults. Children may be particularly susceptible to noise.Objectives: To examine the association between traffic noise exposure during pregnancy and early childhood and adiposity in children.Methods: We identified 40,974 singletons from the Danish National Birth Cohort with parentally given questionnaire information on weight and height at 7-years of age. Road and railway traffic noise were modelled at all historical addresses for two exposure periods (pregnancy and childhood). Adiposity was assessed using BMI z-scores and a dichotomous measure of childhood overweight based on age and sex specific cut-offs. Associations were analyzed using linear regression for BMI z-scores and logistic regression for risk of childhood overweight, adjusting for socioeconomic position, maternal age, parity and degree of urbanization.Results: We found both pregnancy and childhood exposure to be associated with a borderline statistically significant higher risk for childhood overweight (odds ratio =1.05, 95% confidence interval: 0.99-1.12 for childhood exposure). There was no associations between traffic noise and BMI z-scores. We found no associations between railway noise and adiposity.Conclusions: We found suggestions of a positive association between road traffic noise and risk of overweight in 7-years old children.