Abstract
OBJECTIVE: Assess postintervention and dose effects of a child obesity prevention program, delivered from pregnancy through the age of 3 years, on child weight outcomes at the ages of 4 and 5 years among low-income Hispanic families. METHODS: As postintervention follow-up of the Starting Early Program (StEP) randomized controlled trial, StEP enrolled pregnant people in the third trimester to standard care control or the StEP intervention, which provided 15 nutrition and parenting support sessions. We analyzed differences in weight-for-age z scores (WFAz) and obesity status by group within intervention group analyses of program dose and moderation by adverse social drivers of health (SDoH). RESULTS: Weight data were available for 312 and 264 children aged 4 and 5 years, respectively. Mean WFAz (0.59 [1.08] vs 0.52 [1.16], P = .55; 0.60 [1.07] vs 0.58 [1.22], P = .86) and proportion with obesity (15.2% vs 15.6%, P = .90; 16.2% vs 19.5%, P = .47) were not different by intervention status at the ages of 4 and 5 years. The mean (SD) number of sessions attended was 8.7 (4.2) with the highest tertile attending 11 sessions or more. Lower WFAz and obesity prevalence were found for families with top tertile attendance. In moderation analysis, impacts on weight in children aged 5 years were greater for families with low social support compared high social support. CONCLUSION: Participation in StEP was not associated with postintervention differences in child weight. Higher attendance was associated with lower obesity prevalence, while treatment effects were greater for families with low social support. This highlights the need to evaluate program dose on long-term outcomes, especially for those with adverse SDoH.