Life course adiposity and adolescent depressive symptoms among Hong Kong adolescents.

PURPOSE

Depression is a public health issue, which often emerges in adolescence. Adiposity may be a factor in this emergence; however, in Western settings, both adiposity and depression tend to be socially patterned, making it unclear whether any association is biologically based or contextually specific.

METHODS

Multivariable analysis was used to assess the adjusted association of birth weight and life course body mass index (BMI) z score (at 3 and 9 months and 3, 7, 9, 11, and 12 years of age) and changes in BMI z score with adolescent depressive symptoms score at ∼14 years of age, assessed from Patient Health Questionnaire-9 (PHQ-9) in a population-representative Chinese study, Hong Kong's "Children of 1997" birth cohort, which has little social patterning of birth weight or BMI. We also assessed whether associations varied with sex.

RESULTS

PHQ-9 was available for 5,797 term births (73% follow-up). Birth weight z score, BMI z scores at 3 and 9 months and at 3, 7, 9, 11, and 12 years of age, and successive BMI z score changes had little association with PHQ-9 at ∼14 years of age, adjusted for socioeconomic position, parental depressive symptoms, and survey mode.

CONCLUSIONS

In a developed non-Western setting, life course adiposity does not appear to be a factor in the development of depressive symptoms in adolescence, suggesting that observed associations to date may be contextually specific rather than biologically based.