ReviewAnorexia nervosa and bone metabolism

- Anorexia nervosa is associated with significant bone loss and an increased risk of fracture.
- The bone loss in anorexia nervosa is a result of hormonal adaptations to a state of chronic under-nutrition.
- There are a number of therapeutic strategies, currently under investigation, that may be effective in reducing anorexia nervosa-associated bone loss.

Anorexia nervosa (AN) is a psychiatric disorder characterized by self-induced starvation with a lifetime prevalence of 2.2% in women. The most common medical co-morbidity in women with AN is bone loss, with over 85% of women having bone mineral density values more than one standard deviation below an age comparable mean. The low bone mass in AN is due to multiple hormonal adaptations to under nutrition, including hypothalamic amenorrhea and growth hormone resistance. Importantly, this low bone mass is also associated with a seven-fold increased risk of fracture. Therefore, strategies to effectively prevent bone loss and increase bone mass are critical. We will review hormonal adaptations that contribute to bone loss in this population as well as promising new therapies that may increase bone mass and reduce fracture risk in AN.