Context: Anorexia nervosa, characterized by extreme low body weight due to reduced nutrient intake, is associated with severe bone loss. Peptide hormones, including amylin, GIP, and GLP2, are released immediately after nutrient intake and may be involved in the regulation of bone turnover.
Objective: To investigate fasting levels of amylin, GIP, and GLP2 and their relationships with bone mineral density (BMD) in women with anorexia nervosa compared to healthy controls.
Design: Cross-sectional.
Setting: Clinical Research Center.
Study participants: 15 women with anorexia nervosa and 16 healthy controls.
Intervention: None.
Main outcome measures: Fasting serum amylin, GIP, and GLP2, and BMD.
Results: Women with anorexia nervosa had significantly lower fasting serum amylin and GIP levels than healthy controls. Fasting serum GLP2 levels were not significantly different between groups. Fasting amylin levels were positively associated with BMD and Z-score at the PA spine, total hip, and femoral neck. Fasting amylin levels were also positively associated with weight and percent fat; after controlling for these variables, amylin was still a significant predictor of BMD and Z-score at the femoral neck and of Z-score at the total hip. In the anorexia nervosa group, there was a trend toward an inverse association between amylin and C-terminal telopeptide (CTX) levels (R=-0.47, p=0.08). GIP and GLP2 levels did not predict BMD at any site.
Conclusion: Decreased secretion of amylin may be a mechanism through which reduced nutrient intake adversely affects BMD in anorexia nervosa.