Community-dwelling women with anorexia nervosa have a high prevalence of medical abnormalities, including problems with the metabolism, blood and skeleton, Harvard Medical School in Boston researchers report.

The findings underscore the importance of medical evaluation of patients with anorexia nervosa along with psychological treatment, Dr. Karen K. Miller and colleagues report in the Archives of Internal Medicine.

The researchers recruited 214 women with anorexia nervosa through advertisements and referrals. Medical histories of all participants were obtained, along with a nutritional evaluations, blood samples and bone mineral density tests.

Less than 15 percent of the women had normal bone densities, Miller and her colleagues found, while 38.6 percent were anemic, 34.4 percent had low white cell counts and 41.3 percent had slow heart rates.

Low sodium and potassium levels were each seen in 19.7 percent of the women, while low potassium - known to be associated with purging - was seen even among women who denied purging behavior. This may have been because the women were reluctant to admit to purging, the researchers note, but an association between low weight and low potassium levels cannot be ruled out.

“Even if a woman with anorexia nervosa denies purging, a potassium level is really important,” Miller told Reuters Health, pointing out that low potassium levels can lead to potentially deadly heart arrhythmias.

Other abnormalities included low blood pressure in 16.1 percent of patients, low body temperature in 22.4 percent and elevation of liver enzymes, indicative of liver disease, in 12.2 percent.

Physicians should consider a diagnosis of anorexia nervosa in women of low weight who have these abnormalities, Miller said, noting that as many has half of cases of anorexia nervosa go undiagnosed in the medical setting. Conversely, she added, the absence of such abnormalities should not rule out the possibility of the disorder.

Discussing these abnormalities with an anorexia nervosa patient can help with the denial common among those with the disorder, Miller said. “It can be extremely useful to motivate some patients towards recovery, for them to actually see in some objective measure the damage that is happening to their bodies.”

SOURCE: Archives of Internal Medicine, March 14, 2005.