Transdermal Estrogen in Older Premenopausal Women With Anorexia Nervosa

Anorexia nervosa (AN) is a prevalent psychiatric disorder affecting up to 1% of college-aged women in the US and an increasing number of women over 30 years of age. Among the many medical co-morbidities associated with AN, the most common is significant bone loss, which can persist despite weight recovery. Nearly 50% of women with AN have osteopenia with an additional 30% meeting WHO criteria for osteoporosis. Importantly, this severe bone loss is associated with an increased fracture risk. Nearly 30% of women with AN report a history of a fracture and a prospective study demonstrated a 7-fold increased risk of fracture in women with AN compared to age-matched controls. Because AN is a chronic disease that can persist despite psychiatric and nutritional counseling, the bone loss and increased fracture risk can persist and lead to lifelong morbidity. Therefore, finding a treatment for bone loss associated with AN is of critical importance. This 6 month open-label study will investigate in women (ages 25 to 50 years old) with AN whether treatment with transdermal estrogen replacement will increase bone mineral density (BMD), improve parameters of bone microarchitecture as assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT), and improve bone strength as estimated by microfinite element analysis.