TUESDAY, June 13, 2006 (HealthDay News) -- The antidepressant Prozac doesn't help women struggling with anorexia nervosa maintain a normal body weight, and it doesn't reduce their risk of relapsing, a new study found.
This revelation comes after years of prescribing the drug for patients suffering from the life-threatening eating disorder.
"People should not rely on medication which doesn't look terribly effective, but turn their attention to other treatments which may be more useful," said study lead author Dr. B. Timothy Walsh, a professor of psychiatry at New York State Psychiatric Institute at Columbia University Medical Center.
Dr. Onelia G. Lage, an associate professor of pediatrics at the University of Miami Miller School of Medicine, added that the finding "makes sense because anorexia is not a medically treated disease. So, yes, you're going to have relapse if the underlying family and psychological function continues to exist."
Anorexia nervosa, a disorder marked by extreme dieting and other behaviors to keep body weight abnormally low, has the highest mortality rate of any psychiatric illness. The disorder, which primarily affects women, also has a high rate of relapse, with some 30 percent to 50 percent of patients requiring re-hospitalization within one year of their initial discharge.
A sizable number of patients with the disorder are treated with antidepressants such as Prozac, even though there's little direct evidence to support the practice. Medical professionals have largely relied on indirect evidence.
"A lot of people with anorexia, even after they regain weight, have symptoms of anxiety and depression, and clearly fluoxetine [the generic name for Prozac] is useful for those people," Walsh explained. "Also, fluoxetine is clearly efficacious in the treatment of bulimia, and a number of people with anorexia have these symptoms."
In addition, one small trial involving patients with anorexia found the drug did help prevent relapse.
For the new study, 93 women aged 16 to 45 with anorexia were randomly assigned to receive Prozac or a placebo. At the time of enrollment in the trial, the participants were completing intensive inpatient or day-program treatment at the New York State Psychiatric Institute or Toronto General Hospital. All had regained weight to a minimum body mass index (BMI, a ratio of weight to height) of 19 before they could be enrolled in the trial. A BMI ranging from 18.5 to 24.9 is considered normal weight.
According to the study, a similar percentage of women assigned to Prozac and the placebo maintained a BMI of at least 18.5 and remained in the study for a full year -- 26.5 percent in the Prozac group and 31.5 percent in the placebo group. There were also no significant differences in the amount of time it took to relapse. At one year, 45 percent of the placebo group and 43 percent of the Prozac group had not relapsed.
The study results appear in the June 14 issue of the Journal of the American Medical Association.
The findings don't rule out the possibility that drugs such as Prozac might work at a different point in time, for example, after a person has maintained a normal body weight for six months. Starting the drug when a patient is at a lower weight does not work, other trials have shown.
The new results also don't shed light on effective treatments for younger patients. "The biggest problem we're having is with 9- to 12-year-olds," Lage said.
The age group in the trial was representative of most patients seeking treatment, Walsh said. And the bottom line, at least for this age group, is that approaches borrowed from other psychiatric disorders, such as depression and anxiety, do not work for anorexia.
"It just doesn't respond like other disorders that you might think it is similar to," Walsh said. "That suggests to me that we need to think about the disorder in more innovative and fresher terms. We really need some new thinking, and thinking that is much more specific to anorexia as opposed to borrowing techniques from things that look similar."
Salvation may lie somewhere outside of drugs, Walsh said. "I'm afraid this study falls consistently in the long history of medication trials, almost none of which have been positive," he said. "We have yet to discover or identify an effective medication for anorexia."
The National Eating Disorders Association can tell you more about anorexia nervosa.