Salivary and serum insulin-like growth factor (IGF-1) assays in anorexic patients

Objectives. The purpose of this study was to measure the salivary and serum free IGF-1 concentration of patients with anorexia nervosa (AN) in comparison to an average population. Methods. A controlled clinical trial was designed for an age- and gender-matched group of 121 AN patients and 77 healthy individuals. A clinical examination was made and blood and salivary samples were taken during the acute stage of AN (BMI < 15 kg/m(2)) in the first week of hospitalization. An enzyme immunoassay (ELISA) suitable for measuring free IGF-1 was used. Results. Anorexic patients had significant reductions in salivary unstimulated flow rate (UFR), pH and free IGF-1 levels in their saliva and serum. Significant correlations between serum IGF-1 and BMI; salivary IGF-1 and UFR and pH were detected. Conclusions. Salivary and serum IGF-1 analyses appear to be a reliable biochemical indicator of malnutrition in AN patients. Measurement of salivary IGF-1 levels would allow new perspectives in monitoring AN in its early stages.