Bone metabolism and osteopenia in eating disorders

Bone loss is a potentially debilitating condition in women with eating disorders. Complications may include failure to achieve peak bone mass, increased risk of premature fractures, and inability to reach the height potential. We therefore conducted a comprehensive evaluation of 58 women with anorexia nervosa (AN), bulimia (BUL) and anorexia/bulimia (AB), comparing bone mineral density (BMD) to physical parameters, biochemical indices, and markers for bone formation and resorption. BMDs were significantly lower in patients with AN than in those with AB and BUL, and overt osteopenia was uncommon in AB and BUL. Hypercortisolism was the best laboratory marker to assess the risk of osteopenia in patients with AN. However, there were no associated changes in bone formation or resorption parameters. No direct correlation was found between BMD and body mass index, estrogen deficiency, tubular reabsorption of phosphorus, serum vitamin D, PTH, BGP, or alkaline phosphatase levels. Although the prognosis for complete recovery to normal BMD is poor, treatment of the underlying depressive disorder, improvement in nutrition with increased weight, and spontaneous resumption of menses are associated with restoring bone health.