Dopamine agonist use associated with increased prevalence of impulse control disorders among patients with PD, study data indicate

Among patients with Parkinson's disease (PD), the odds of having an impulse control disorder (ICD) are more than 2-fold for patients who use dopamine agonists as compared with those who do not, according to findings from the large, multicenter, cross-sectional DOMINION study. Researchers used a semistructured interview and formal diagnostic criteria to assess the current (ie, within the previous 6 months) frequency of 4 ICDs in 3,090 patients with PD who were receiving treatment at any of...

Among patients with Parkinson's disease (PD), the odds of having an impulse control disorder (ICD) are more than 2-fold for patients who use dopamine agonists as compared with those who do not, according to findings from the large, multicenter, cross-sectional DOMINION study.

Researchers used a semistructured interview and formal diagnostic criteria to assess the current (ie, within the previous 6 months) frequency of 4 ICDs in 3,090 patients with PD who were receiving treatment at any of 46 movement disorder centers in the United States and Canada. Of these patients, 66% were taking >=1 dopamine agonist and 86.8% were taking levodopa.

The researchers found that 13.6% of the study population had an ICD; problem/pathological gambling was present in 5.0%, compulsive sexual behavior in 3.5%, compulsive buying in 5.7%, and binge-eating disorder in 4.3%. In all, 3.9% of the patients had >=2 ICDs.

ICDs were more common among the patients who were taking dopamine agonists (17.1%) than among those who were not taking these drugs (6.9%; P<.001); this pattern was also observed when the 4 ICDs were evaluated separately.

ICDs were identified in 17.7% of the patients taking a dopamine agonist and levodopa, in 14.0% of the patients taking a dopamine agonist without levodopa, and in 7.2% of the patients taking levodopa without a dopamine agonist. Of the 59 patients who were treated with drugs other than levodopa and dopamine agonists, 1 (1.7%) had an ICD.

In a multivariate analysis, the odds of having an ICD were higher among the patients who were taking a dopamine agonist than among the levodopa-treated patients who were not taking a dopamine agonist (odds ratio [OR], 2.60 [95% CI, 1.97-3.43]; P<.001). At the same time, the odds of having an ICD were higher among those taking a dopamine agonist and levodopa relative to those taking a dopamine agonist alone (OR, 1.42 [95% CI, 1.02-1.98]; P<.001).

There was no significant difference in the prevalence of ICDs between the patients treated with pramipexole dihydrochloride (17.7%) and those treated with ropinirole hydrochloride (15.5%; P=.14). The prevalence of ICDs among the 50 pergolide mesylate-treated patients was 22.0%.

In a multivariate analysis, use of a dopamine agonist and use of levodopa were independently associated with having an ICD, but the odds ratio for having an ICD was higher with the use of dopamine agonists (OR, 2.72; P<.001) than with levodopa (OR, 1.51; P=.01). Other variables associated with having an ICD included being of younger age, unmarried or a current cigarette smoker, living in the United States, and having a family history of gambling problems.

Among the patients who were taking a dopamine agonist, there was no significant association between having an ICD and dopamine agonist dosage in a multivariate analysis, but any levodopa use and higher levodopa dosages were both associated with having an ICD (P=.03 and P=.008, respectively).

Among the patients who were taking levodopa without a dopamine agonist, the results of a multivariate analysis again revealed a significant association between higher levodopa dosages and having an ICD (P=.002). (Weintraub D, et al. Arch Neurol 2010;67:589-595.)

Boehringer Ingelheim Pharmaceuticals Inc., which markets pramipexole under the brand name Mirapex, funded the DOMINION study.