Developmental trajectories of disordered eating in boys and girls and their associations with eating disorder risk factors

Disordered eating (DE) often begins in early adolescence and follows heterogeneous developmental patterns. This study had two main objectives: (1) to identify homogeneous developmental trajectories of DE in adolescents aged 11-16 years and (2) to investigate factors predicting the likelihood of belonging to specific developmental trajectories. Data from a four-wave longitudinal study were analyzed, including participants aged 11 to 16 years (girls n = 167, boys n = 131). Using Growth Mixture Modeling based on the Children's Eating Attitude Test (ChEAT), three distinct developmental trajectories were identified: Low-Stable (16% of participants, exhibiting few DE symptoms that remained stable), High-Stable (36% of participants, consistently displaying high levels of DE), and Medium-Increasing (48% of participants, experiencing moderate DE that increased with age). Important gender differences emerged: more girls belonged to the High-Stable and more boys to the Low-Stable trajectory. Multinomial logistic regression analysis showed that being a girl, higher BMI, perceived social pressure for thinness, and perfectionism were associated with an increased likelihood of belonging to the High-Stable trajectory. Among the ChEAT subscales, Body Concerns was the only one to exhibit exclusively stable trajectories over time. In conclusion, strongly manifested DE symptoms tend to follow a stable course between ages 11 and 16, whereas individuals with moderate DE are more likely to experience an increase in symptoms during this period. Identifying developmental trajectories and their associations with risk factors can facilitate early detection of adolescents in need of urgent attention or targeted interventions and improve the planning of preventive measures.