(PhysOrg.com) -- A rare psychiatric disorder called olfactory reference syndrome makes its victims think they smell bad when they don’t, and while this delusion may on the surface seem less serious than thinking you don’t smell bad when you do, it can have consequences serious enough that psychiatrists are considering listing it as a separate disorder in the Diagnostic and Statistical Manual of Mental Disorders.

Dr. Katharine Phillips, Professor of psychiatry and human behavior at Brown University and Rhode Island Hospital in Providence, Rhode Island, has been studying the syndrome. She said patients tend to be secretive about the disorder, and their suffering can be intense, with around two-thirds of sufferers contemplating suicide because they think their mouth, armpits, or genitals are emitting a foul stench.

A study in the 1970s suggested up to five percent of sufferers may commit suicide, which is a higher rate than for other mental illnesses, while the current study reported one-third had attempted suicide, and over half had been hospitalized for psychiatric illness.

Dr. Phillips said the delusions appear to start in the teenage years, and it is not clear if any drugs or non-medical treatments are effective for the syndrome. Phillips and her colleagues studied 20 patients with the disorder to determine its general characteristics. Their patients, 60 percent of whom were female, had an average age of 33 and had suffered from the syndrome since their mid teens.

The patients spent up to eight hours a day thinking about their imagined odor, and many compulsively sniffed and cleaned themselves, sometimes using a whole bar of soap each day. Half the patients changed clothes repeatedly during the day, and almost all used products such as deodorants, powders or perfumes (in one case drinking it) to mask the perceived smell.

Dr. Phillips said 75 percent of the patients felt others were taking notice of their smell, and 85 percent were convinced they smelled bad and could smell themselves, even though everyone around them reassured them they did not. They also misinterpreted signs such as opening a door or window, or rubbing the nose as confirmation they smell.

It is not known how many people suffer from olfactory reference syndrome because people with the syndrome tend to isolate themselves. Many confine themselves in their homes, where they repeatedly sniff themselves, shower and wash their clothes. The syndrome has been known for more than a century, but it is not a well-known disorder.

Dr. Phillips said few patients sought psychiatric treatment, seeking the help of dentists or non-medical therapists instead, but these have not been shown to be effective. She said cognitive behavioral therapy (CBT) has been helpful in some cases.

Dr. Phillips presented the results of her research at the American Psychiatric Association annual meeting in New Orleans held on May 22-26.

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