Bone Loss in Women with Anorexia Nervosa

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The summary below is from the full report titled "Prevalence and Predictive Factors for Regional Osteopenia in Women with Anorexia Nervosa." It is in the 21 November 2000 issue of Annals of Internal Medicine (volume 133, pages 790-794). The authors are S Grinspoon, E Thomas, S Pitts, E Gross, D Mickley, K Miller, D Herzog, and A Klibanski.

What is the problem and what is known about it so far?

Anorexia nervosa is an eating disorder that is common among young women. Persons with anorexia nervosa are obsessed with being thin and severely limit the amount that they eat. As a result, they become undernourished. Health consequences of this serious and potentially deadly disease include osteopenia and osteoporosis. Osteopenia means that bones become less dense. When this bone thinning becomes severe, it is called osteoporosis. Persons with osteoporosis are at high risk for broken bones. Bone loss can begin after only 6 months of anorexia nervosa. Little is known, however, about the amount of bone loss at different places in the skeletons of persons with anorexia nervosa.

Why did the researchers do this particular study?

To examine the amounts of bone loss at different sites in the skeletons of women with anorexia nervosa and to determine whether any patient characteristics are associated with bone loss.

Who was studied?

The study included 130 women with anorexia nervosa who were recruited through community advertisements or by their doctors. Almost all of the women were white. They had had anorexia nervosa for an average of about 5.5 years.

How was the study done?

The researchers interviewed and examined all study patients. They also measured the density of each woman's bones at several locations in the spine and the hip by using a special x-ray test.

What did the researchers find?

Osteopenia and osteoporosis were common at all sites. Nearly half of the women had osteopenia at the hip, and 16% had osteoporosis at the hip. More than half had osteopenia at the spine, and almost a quarter had osteoporosis at the spine. Over 90% of women had abnormally low bone density at one or more sites in the skeleton. Weight was the factor most related to bone loss. The less a woman weighed, the more likely it was that she would have substantial bone loss.

What were the limitations of the study?

This study measured bone density at a single point in time. It does not tell us what happens to the bones of women with anorexia nervosa over time as the eating problem worsens or improves.

What are the implications of the study?

Bone loss is a very common problem for women with anorexia nervosa. Doctors who care for these women should be aware of this consequence of the disease.