Family income matters! Tracking of habitual car use for school journeys and associations with overweight/obesity in UK youth

Abstract

IntroductionThe aims of this study were to assess associations between car use for school journeys in early childhood and car use for school journeys in later childhood and adolescence, (ii) determine whether an income gradient to habitual car use for school journeys and overweight/obesity exists in the UK, and (iii) assess the extent to which habitual car use for school journeys through childhood and into adolescence is associated with overweight/obesity in adolescence. MethodsData is from sweep three, four, five and six of the UK Millennium Cohort Study. Subjects consisted of 8494 children (4251 girls). Stature and body mass were assessed at age 5 and 14 years and children were categorised as normal weight or overweight/obesity. Commute mode to and from school was parent/carer reported at age 5, 7, 11 and 14 years and habitual car use for school journeys was determined. Family income at age 5 years was determined using equivalised household income. Adjusted logistic and multinomial logistic regression analyses were conducted. ResultsCar use for school journeys at age 5 was positively associated with car use for school journeys at age 7, 11 and 14 years (p < 0.001). Family income at child age 5 was inversely associated with overweight/obese at age 5 and 14 years and positively associated with habitual car use (p < 0.001). Habitual car use for school journeys was not associated with overweight/obesity at age 14 years. ConclusionsCar use for school journeys in early childhood is positively associated with car use for school journeys in later childhood and adolescence. Children living in the highest income households have the lowest rates of overweight/obesity, and there is an income gradient to habitual car use for school journeys. Habitual car use for school journeys through childhood and into adolescence is not positively associated with overweight/obesity in adolescence.