Body image and depressive symptoms in Danish adolescents: A cross-sectional national study

Background: Depressive symptoms are prevalent in adolescents. We aimed to investigate the association between body image and depressive symptoms, and how Body Mass Index (BMI) affects this. Methods: Survey data from 2017 with 9963 9th-grade Danish adolescents. Information from the survey about the exposure, body image, was divided into 3 categories: too fat, too thin, and adequate. Depressive symptoms, was measured with Center for Epidemiological Studies Depression Scale for Children (CES-DC4). BMI was categorized as underweight, normal weight and overweight. We used logistic regression and examined for effect modification by sex and BMI and adjusted for self-esteem and bullying. Results: An association was found between body image and depressive symptoms, when adjusting for BMI, sex, self-esteem, and bullying. The association was strongest for adolescents feeling too fat compared with adolescents feeling adequate OR:1.61(1.45-1.78), for adolescents feeling to thin compared to adequate: OR:1.21 (1.06-1.37). No effect modification by either BMI or sex was found, but those who perceive their bodies in contrast to their reported BMI faced the highest odds of depressive symptoms, and the results were confounded by self-esteem and bullying, that reduced the estimates after adjusting. Limitations: This is a cross-sectional study with limited information regarding drop-out, with risk of selection bias. Conclusion: We found an association between negative body image and depressive symptoms among Danish adolescents. This confirms previous studies and is a relevant aspect to adolescents' mental health, especially the contrast between BMI and perceived body image, and the confounding by self-esteem and bulling, with potential for prevention.