Parent-focused behavioral interventions are ineffective in preventing obesity in children aged 24 months, according to findings from TOPCHILD – a systematic review and individual participant data meta-analysis published Sept. 10 in The Lancet.

Kylie E. Hunter, PhD, et al., analyzed data from 9,128 participants in 17 randomized controlled trials evaluating the effect of parent-focused behavioral interventions on obesity in children vs. usual care, no intervention or attention control. The primary outcome was BMI Ζ score at 24 months of age (±6 months).

The analysis yielded no evidence of an effect of interventions on the primary outcome (±6 months; mean difference –0.01 [95% CI –0.08 to 0.05]; high certainty evidence, ͳ²=0.01; n=6,505; 2,623 missing). Prespecified subgroups, such as priority populations and trial-level factors, were also analyzed, with no differential intervention effects identified.

The authors propose several possible explanations as to why interventions showed no effect on the primary outcome. Some trials investigating newer approaches for behavior change were not eligible for the TOPCHILD analysis. Hunter and colleagues also suggest that interventions may be targeting the wrong age group or may not have reached priority populations in the most need.

They also consider that “included interventions used downstream approaches that require a high degree of individual agency… Yet, obesity is predominantly driven by upstream environmental and socioeconomic factors that are beyond the capacity of the individual to change.”

A longer follow-up period may also be required to see the long-term effects of these interventions. The authors note they will “further examine BMI Ζ scores at [3.5 and 5 year] timepoints once more trials have completed follow up.”