Insulin-like growth factor-1 as an indicator of nutrition during treatment of adolescent girls with eating disorders

AIM: The use of serum insulin-like growth factor-1 (IGF-1) concentrations as an index of nutrition has been analysed in teenage girls with eating disorders and weight loss. METHOD: Blood samples for analysis of IGF-1 were obtained at 349 assessments of 302 patients and biweekly during 56 treatment periods in 46 patients. IGF-1 was related to body size, weight loss, degree of leanness (BMI standard deviation score) and rate of weight loss. RESULTS: At assessment, when most of the girls were on a weight-losing course, serum IGF-1 concentrations were low. Weight loss immediately prior to assessment was the most important predictor of IGF-1. Together with measurements of weight, height, weight loss and BMI standard deviation score the rate of weight loss predicted IGF-1 to 32-55%. During treatment when there was net weight gain, IGF-1 increased in parallel with the BMI standard deviation score, a measure of leanness, and was also influenced by the short-term weight trend. CONCLUSION: The serum IGF-1 concentration is an indicator of nutritional status in adolescents with eating disorders. It is sensitive to short-term weight changes measured in a clinical setting and could be used at assessment and to monitor nutritional rehabilitation.