Serum insulin-like growth factor-i concentrations in the recovery of patients with anorexia nervosa

Anorexia nervosa (AN) can result in extreme malnutrition, and these patients frequently require inordinately large amounts of calories to gain weight during refeeding therapy. Insulin-like growth factor-I (IGF-I) is a polypeptide that mediates many of the anabolic effects of growth hormone. Low levels of IGF-I have been associated with malnutrition and can cause poor weight gain. To clarify the potential relationship of IGF-I to weight gain, serial serum IGF-I, retinol-binding protein and prealbumin levels were measured at admission, 2 weeks and 4 weeks, in 14 consecutive consenting patients admitted for treatment of AN. Baseline IGF-I levels were lower in the patients compared to age-matched controls (mean 20.8±2.5 vs 32.9±2.9 nmol/L, p<0.01). In patients with no weight gain, IGF-I levels were static. There was a stepwise increment in the IGF-I values related to weight gain. Retinol-binding protein and prealbumin, proteins commonly used to assess nutritional status, did not demonstrate important correlations with weight gain. Further studies are required to determine whether or not initial low IGF-I levels impede weight gain in AN patients and whether treatment with IGF-I (possibly in combination with growth hormone) may be of benefit in this disease process.