Gambling problem can affect restless legs patients

NEW YORK, Feb 1 (Reuters) The impulsive behavior that sometimes develops as a side effect of treatment with ''dopamine agonists'' drugs may not be limited just to patients with Parkinson's disease.

Patients with restless legs syndrome who are treated with a drug belonging to this class may also be at increased risk for pathologic gambling, according to a report in the medical journal Neurology.

Dopamine agonists are a class of drugs that contain agents commonly used to treat Parkinson's disease and restless legs syndrome, both neurological disorders. Some of these drugs commonly used for one or both conditions include Requip (generic name ropinirole), Mirapex (pramipexole) and Sinemet (levodopa plus carbidopa).

Dr M Tippmann-Peikert and colleagues from the Mayo Clinic College of Medicine, Rochester, Minnesota, conducted a review of the available medical literature, and found that the lifetime prevalence of pathologic gambling in the general US population is 1.93 percent.

''A similar or even higher frequency has been suggested in patients with Parkinson's disease treated with dopamine agonists,'' they report in the medical journal Neurology The researchers described the case history of three patients -- two middle-aged women and an older man -- with restless legs syndrome who became pathologic gamblers after treatment with dopamine agonists began.

Restless legs syndrome is a neurological disorder that causes unpleasant sensations in the legs and an uncontrollable urge to move to get relief. Patients have described the sensations as a burning or creeping feeling, or like insects are crawling inside the legs.

What characterised the syndrome is that patients primarily develop symptoms when they are trying to relax or sleep.

None of the three patients had signs of parkinsonism on neurologic examination, and none was aware of the possible link between dopamine agonists and pathologic gambling reported for Parkinson's disease patients. One of the patients had never gambled before starting dopamine agonist therapy, and the other two patients had just a little past experience of recreational gambling.

At the time gambling commenced or worsened, the three patients were taking an average of 0.5 mg/day of pramipexole, and one other patients was on a daily dose of 0.25 mg of ropinirole. The gambling behavior got worse with each dose increase. The patients had been treated with dopamine agonists for an average 9.3 months when the gambling compulsions began.

The patients reported gambling losses of more than 0 in a year, 140,000 dollars, and ''several hundred thousand dollars.'' Once dopamine agonist therapy was discontinued, the pathologic gambling disappeared or drastically decreased in all three patients.

Two of the patients continued to gamble occasionally and without much financial loss.

''Future studies are needed to establish if the prevalence of this condition in this population is different from that in the general population,'' Tippmann-Peikert and colleagues note.

''However, the close time relationship of development or significant worsening of gambling behaviors in our patients as well as the resolution upon discontinuation of the dopaminergic agents suggest a causative association,'' they conclude.

REUTERS SI ND1045