FRIDAY, March 16, 2007 (HealthDay News) -- Antidepressants don't help people with the compulsive stealing disorder kleptomania, a new study found.
The findings, by researchers at the Stanford University School of Medicine, came as no surprise to experts in the mental health field, where kleptomania is known as a particularly stubborn problem.
"Kleptomania doesn't respond very well to anything at all," said Dr. Norman Sussman, a professor of psychiatry at New York University School of Medicine. "Even therapy is often useless. People will steal things even after getting caught. It's truly a compulsion."
The study authors, however, did not rule out the possibility that certain medications, even the one used in the trial, might still prove to be an effective treatment for some people.
Some 1.2 million Americans are believed to suffer from kleptomania, which propels them to impulsively steal inexpensive and unneeded items. Unlike shoplifting, stealing related to kleptomania is not planned and is not motivated by need or financial gain.
According to background information in the study, kleptomania has been estimated to account for 4 percent to 10 percent of shoplifting in the United States. With shoplifting causing estimated annual losses of $10 billion to $50 billion, kleptomania's toll is substantial.
"People with kleptomania rarely seek treatment, because they're afraid of the legal consequences or don't know that treatment may help," said study author Dr. Lorrin Koran, a professor of psychiatry and behavioral sciences at Stanford. "Some people do benefit from treatment."
An earlier "open-label" trial showed a 78 percent success rate with antidepressants known as selective serotonin reuptake inhibitors (SSRIs). But open-label trials, in which information about who is taking medication and who is taking a placebo is public, are notoriously unreliable.
"In open-label trials, it only looks like they might work," Sussman said. "It's wishful thinking."
For the new study, published in the March issue of the Journal of Clinical Psychiatry, the researchers looked at 24 people aged 20 or older who had been diagnosed with kleptomania at least one year earlier.
The participants were randomly chosen to take either the SSRI escitalopram (Lexapro) or a placebo. The study was funded by Lexapro's maker, Forest Laboratories. Response rates turned out to be the same in both groups, suggesting that the earlier effects in the open-label trial were due to a placebo effect.
In the second phase of the study, conducted as a double-blind, placebo-controlled trial with 15 participants, no benefit was seen. About the same proportion of participants relapsed in each group.
The small size of the study means the potential of this treatment can't be dismissed, the authors stated.
"Some of these people told me that they had been through many other treatments, had been in jail, divorced, nothing stopped them from thinking about stealing," Koran said. "But when they took the drug, they weren't thinking about it. They didn't have the urge. It's hard to believe that that's a placebo effect."
Koran suspects the disorder is more complicated than experts realize.
"I think this is a behavior that has different biological roots in different people," he said. "For some, the drug was active on serotonin and probably was effective, and for others, it was a placebo effect. It's also possible the drug worked for some and lost its effect. If we had increased the dose, they may have continued to see a benefit. We're on the outside looking in, and we don't know what's going on in the brain.
But others didn't necessarily agree.
"This doesn't contradict the weight of evidence," Sussman said. "This simply confirms what we already suspected."
A second study by the same researchers looking at the same drug found that Lexapro also did not help people with compulsive buying disorder.
Again, this finding contradicts prior results from an open-label trial showing a benefit. The latest trial, a randomized one, involved only 17 participants.
For more on kleptomania, visit New York University Medical Center.