Plasma brain‐derived neurotrophic factor in prepubertal obese children: results from a 2‐year lifestyle intervention programme

CONTEXT: Brain-derived neurotrophic factor (BDNF) is a neurotrophin potentially involved in the pathophysiology of obesity and metabolic syndrome in adults. In children, it has scarcely been studied. OBJECTIVE: To analyse plasma BDNF and its relationship with metabolic syndrome components before and after 2 years of a lifestyle intervention programme in a prepubertal obese cohort. DESIGN AND SETTING: Case-control study with a 2-year prospective follow-up in a referral paediatric endocrine outpatient centre. PATIENTS AND METHODS: Seventy-three prepubertal obese children, 8·03 ± 1·08 years old, and 47 age- and gender-matched lean controls were studied. Anthropometric parameters, blood pressure, platelet count (PLT), oral glucose tolerance test, homoeostatic model assessment for insulin resistance (HOMA-IR), lipid profile, BDNF, diet and physical activity were evaluated. Weight loss was considered if z-score body mass index (BMI) decreased at least 0·5 SD. RESULTS: At baseline, BDNF tended to be lower in prepubertal obese children compared with lean controls (P = 0·076). BDNF did not correlate with any metabolic syndrome component. After 2 years, obese patients showed an increase in BDNF. Regression model analysis adjusted by age, sex, puberty, BMI, PLT and HOMA-IR showed that BDNF increased in subjects who lost weight (P = 0·036), practiced sports (P = 0·008) and had an adequate carbohydrate intake (P = 0·032). CONCLUSIONS: Plasma BDNF tends to be lower in obese prepubertal children than in lean controls, is not related to any other metabolic syndrome component and increases after a lifestyle intervention programme.