Introduction Worldwide, the prevalence of childhood obesity has not abated, indicating that prevention strategies, traditionally implemented at the individual- level, may not be effective. Conceptualising childhood obesity within multiple levels of influence, specifically within residential communities and over the lifecourse, is necessary to design effective prevention strategies that shift the distribution of risk downward.

Methods Participants of the Québec Longitudinal Study of Child Development (n=1588) comprised the sample for analysis. Standardised BMI measurements from 4 to 10 y of age and a semi-parametric mixture modelling method were used to estimate developmental trajectories of weight change. The influence of the residential environment on weight trajectories was estimated after controlling for social and early life factors, such as SES and birthweight.

Results Four distinct weight trajectory groups were estimated: (1) Low- increasing (7.1%), (2) Low/medium-increasing (35.2%), (3) Medium/high- increasing (47.4%), and 4) High-stable (10.3%). Switching from urban to rural living decreased weights in Group 1, but increased weights in Group 4. In Group 2, changing from urban to medium density living increased weights. For Group 1, moving to a more cohesive neighbourhood increased weights, and moving to a more highly disordered neighbourhood decreased weights. Compared to the other three groups, Group 4 children were more likely to be overeaters and have obese mothers.

Conclusion The characteristics of residential environments may play a role in childhood weight status beyond social and early life factors. These characteristics may have differing effects within the population, so a ‘one-size fits all’ strategy for intervention may not be appropriate.