ESPE Abstracts

Background: Over the last thirty years, the incidence of adolescent obesity has quadrupled. While the physical risks of adolescent obesity have been well researched, there has been little research on its impact on mental health status and cognitive abilities. In the present study, we intend to examine whether nutritional intervention and weight loss affect executive functions and levels of depression of adolescent girls with overweight/obesity (OW/OB).

Methods: This prospective, interventional study included healthy adolescents aged 12-16 years. Girls with OW/OB (BMI percentage ≥ 85 CDC) were randomly assigned 1:1 to either nutritional intervention or no intervention. Participants in the intervention group received 12 weekly sessions with a dietitian, who gave evidence-based dietary recommendations aimed at lifestyle change. Control group members received no dietary intervention during the study period except for a single session at the end of the study. A second control group of healthy girls with normal weight (NW) was also enrolled. Demographics, anthropometric indices, and lab tests were collected at enrollment and at the end of the study after 12-24 weeks. At the beginning and at the end of the study, all participants took a test assessing psychological functions, and validated questionnaires regarding depression, state-trait anxiety, strengths and difficulties, self-esteem, body image, and quality of life.

Results: Seventy-two girls completed the study: 24 girls with OW/OB assigned to nutritional intervention (BMI-SDS 1.59±0.36), 24 with OW/OB assigned to no intervention (BMI-SDS 1.69±0.45), and 24 controls with NW (BMI-SDS 0.33±0.55). At baseline, NW girls had higher scores than OW/OB girls in recall memory (P=0.039), inhibition (P=0.024), and resilience (P=0.027). At the end of the study, BMI-SDS decreased only in the intervention group (P<0.001). The cognitive tests showed an improvement after intervention in the treatment group in flexibility (P<0.001), recall memory (P=0.011), executive functions (P<0.001), emotional bias (P=0.045), overall emotion (P=0.025) and overall self-regulation (P=0.022). Girls in the intervention group showed an improvement in self-esteem after intervention (P=0.050). There was a trend for improvement in the QL school sub-scale for the intervention group (P=0.055). No between-group differences were observed in baseline as well as the change depression questionnaire.

Conclusions: The results of the study indicate that normal-weight girls have higher cognitive abilities in several parameters compared to overweight/obese girls, and that intervention for weight loss may improve some of these measures in overweight/obese girls. Further research in this field is warranted.