Dietary Intake and Anthropometric Measurement at Age 36 Months Among Aboriginal and/or Torres Strait Islander Children in Australia: A Secondary Analysis of the Baby Teeth Talk Randomized Clinical Trial

IMPORTANCE: Interventions to reduce early childhood caries should be examined for their effects on anthropometry given their design to improve children’s diets. OBJECTIVE: To compare the outcomes of dietary intake, anthropometric measurements, and blood pressure measurements between children at age 36 months in the immediate intervention group vs those in the delayed intervention group. DESIGN, SETTING, AND PARTICIPANTS: This secondary analysis was a follow-up to the 2-group Baby Teeth Talk randomized clinical trial conducted across the state of South Australia, Australia. Participants were Aboriginal and/or Torres Strait Islander children and their caregivers who were randomized to the immediate intervention group or delayed intervention group. The intervention was provided from February 1, 2011, to May 31, 2012. The prespecified follow-up when the participating children were aged 36 months was conducted from November 1, 2014, to February 28, 2016, in participant homes or public locations. Data were analyzed from October 5, 2018, to April 29, 2019. INTERVENTIONS: The immediate intervention group received the intervention during pregnancy and at 6, 12, and 18 months of age. The delayed intervention group received the intervention at 24, 30, and 36 months of age. Both groups received an intervention consisting of free dental care for mothers, fluoride varnish on children’s teeth, anticipatory guidance on oral health and dietary advice, and motivational interviewing. MAIN OUTCOMES AND MEASURES: Dietary intake was measured with a caregiver-completed, 17-item food frequency questionnaire. Frequency of consumption of discretionary foods and beverages were the main dietary outcomes. Children’s weight, height, and mid–upper arm circumference were measured and converted to age- and sex-specific z scores. Body mass index z score was the main anthropometric outcome. RESULTS: A total of 330 children were followed up to age 36 months among the 448 mothers and 454 children who were randomized to the 2 groups. At baseline, the women had a mean (SD) age of 24.9 (5.9) years, and the children had a mean (SD) weight of 3.3 (0.6) kilograms at birth, and 205 were boys (46%); sex was not recorded for 63 children (14%). Diet outcomes were similar between the groups. For example, the mean (SD) intake of discretionary beverages by the immediate intervention group was similar to that by the delayed intervention group (507 [536] mL/d vs 520 [546] mL/d; adjusted mean difference [MD], −16 [95% CI, −133 to 102] mL/d; P = .79). Height was similar between the 2 groups, but the mean (SD) z scores of weight (0.7 [1.0] vs 0.4 [1.0]; adjusted MD, 0.3 [95% CI, 0.1-0.5]; P = .02), arm circumference (1.6 [1.0] vs 1.3 [0.9]; adjusted MD, 0.2 [95% CI, 0.1-0.5]; P = .03), and body mass index (1.1 [1.1] vs 0.9 [0.9]; adjusted MD, 0.2 [95% CI, 0.0-0.4]; P = .04) were higher in the immediate intervention group than the delayed intervention group. CONCLUSIONS AND RELEVANCE: This study found no differences in dietary intakes between children who received an intervention to reduce dental caries early and those who received it later. At age 36 months, children in the immediate intervention group had greater z scores for weight, arm circumference, and body mass index than their counterparts in the delayed intervention group, suggesting a potential implication of oral health interventions for anthropometric outcomes. TRIAL REGISTRATION: ANZCTR Identifier: ACTRN12611000111976