The association between the duration and degree of adiposity and appetitive trait trajectory profiles from childhood into early adolescence - results from the Generation XXI cohort.

Background: Body weight in childhood may predict appetitive traits. However, studies on the accumulated effect of adiposity and approaches using the clustering of different appetitive traits are lacking.

Objective: To test associations between a cumulative measure of adiposity [from 4 to 13 years old (y)] and appetitive trait trajectory profiles (from 7 to 13 y), as well as to explore whether body mass index (BMI) at specific ages is associated with these profiles, independently of the cumulative BMI.

Methods: Participants are from the Generation XXI birth cohort (Porto, Portugal) with weight and height measured at 4, 7, 10 and 13 y and complete data in variables of interest (final sample of n = 3339). Age- and sex-specific adjusted BMI standard deviation scores were calculated. The duration and degree of BMI were summarized through the BMI area under the curve (BMI_AUC), as an indicator of accumulated adiposity. Appetitive traits were assessed at 7, 10 and 13 y, using the validated Children's Eating Behaviour Questionnaire. Six previously identified profiles of appetite (groups of individuals with similar patterns of trajectories) were considered: 'moderate appetite' (reference profile), 'small appetite but increasing', 'small to moderate appetite', 'avid appetite', 'increasing appetite' and 'smallest appetite'. Multinomial logistic regressions tested associations between BMI_AUC and profiles.

Results: The median monthly exposure to BMI_AUC was 17.4 kg/m². Except for 'increasing appetite', BMI_AUC was associated with all profiles: positively with the 'avid appetite' (OR = 1.47, 95% CI: 1.40-1.55) and negatively with the remaining ones, particularly with 'smallest appetite' (OR = 0.78, 95% CI: 0.73-0.83). Having overweight/obesity at 7 y increased 113% the odds of having an 'avid appetite' profile (OR = 2.13 95% CI: 1.42-3.21).

Conclusion: Children with the highest cumulative adiposity between 4 and 13 y were more likely to present an 'avid appetite' during childhood. Additionally, having excessive weight at age 7 may indicate a higher appetite in subsequent years.