Patients with anorexia nervosa (AN) generally do not want to be treated and will try to deceive primary care physicians and mental health care professionals by denying the psychological aspects of their disorder and the seriousness of their behavior, warned Katherine Halmi, M.D., who has treated patients with eating disorders for more than 30 years.
Halmi, professor of psychiatry and director of the Weill Medical College of Cornell University's eating disorders program at New York-Presbyterian Hospital, Westchester Division (White Plains, N.Y.), recently cautioned attendees at the 2nd World Congress on Women's Mental Health that, despite individuals with AN being underweight, they are often able to convince primary care physicians and others that they do not meet AN diagnostic criteria.
"These patients will go onto Web sites and find out all kinds of information on how to trick the doctors. So if a physician asks them, 'Are you afraid of becoming fat?', most of them will answer 'no,'" said Halmi.
Consequently, if an individual comes in underweight and suffering from constipation, amenorrhea and bradycardia, the physician should consider the possibility of AN, regardless of what the patient says, Halmi advised. Also, it may be necessary to interview the patient's family members to learn that the patient is severely dieting or exercising excessively. Laboratory findings will help clarify the diagnosis, but they differ somewhat depending on whether the individual has the restricting or binge-eating/purging type of AN (see Table for possible findings on physical examination with AN or bulimia nervosa [BN]).
"If [patients] are just restricting food intake and not binging and purging, their laboratory tests will show a low white blood count, and mildly depressed T3, and a low fasting blood sugar," said Halmi.
If they have the binge/purge type of AN, Halmi said, the patients might have other problems such as electrolyte abnormalities (e.g., hypokalemia) and elevated serum amylase concentration due to enlarged salivary glands.
Patients with AN may also have electrocardiographic abnormalities, she said, which are "far more serious, since these patients can die during a cardiac arrest or arrhythmia."