Effects of dopamine agonist dose and gender on the prognosis of impulse control disorders in Parkinson's disease.
BACKGROUND
Cross-sectional studies have demonstrated that Parkinson's disease patients have an increased risk of impulse control disorders, and that the disorders frequently co-exist with depressive symptoms. There have been no previous large-scale prospective studies investigating predictive and prognostic factors of these disorders.


METHODS
A population of 290 Parkinson's disease patients was studied at baseline and approximately 15 months later. The same screening methodology was used at both time-points (demographic and medication data together with the Questionnaire for Impulsive-compulsive Disorders in Parkinson's disease and the Beck Depression Inventory). The data was analyzed separating patients with and without impulse control disorders at baseline to obtain clinically useful prognostic factors.


RESULTS
In patients who had impulse control disorders at baseline (n = 119), high dopamine agonist dose was associated with the presence of disorders at follow-up. Dopamine agonist levodopa equivalent daily dose over 160 mg was significantly associated with impulse control disorders with a positive predictive value of 92.5% (95% confidence interval 79.6%-98.4%). In addition, females had a better prognosis of impulse control disorders compared to males. The development of novel impulse control disorders (no disorder at baseline, disorder at follow-up) was associated with a concurrent increase in depression scores.


CONCLUSIONS
The results suggest that dopamine agonist dose and gender are associated with the prognosis of impulse control disorders. Symptoms of depression emerge together with novel impulse control disorders in Parkinson's disease.
Department of Neurology, University of Turku and Turku University Hospital, Finland. jtjout@utu.fi
Juho
J
Joutsa
Kirsti
K
Martikainen
Tero
T
Vahlberg
Valtteri
V
Kaasinen
D000368:Aged; D000547:Amantadine / Q000008:administration & dosage; D000928:Antidepressive Agents / Q000008:administration & dosage; D000978:Antiparkinson Agents / Q000008:administration & dosage / Q000009:adverse effects; D003625:Data Collection; D003863:Depression / Q000188:drug therapy / Q000453:epidemiology; D018450:Disease Progression; D007174:Disruptive, Impulse Control, and Conduct Disorders / Q000139:chemically induced* / Q000188:drug therapy* / Q000453:epidemiology; D018491:Dopamine Agonists / Q000008:administration & dosage* / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007980:Levodopa / Q000008:administration & dosage / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D008996:Monoamine Oxidase Inhibitors / Q000008:administration & dosage; D010300:Parkinson Disease / Q000188:drug therapy* / Q000453:epidemiology; D011237:Predictive Value of Tests; D015995:Prevalence; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D057566:Self Report; D017678:Sex Distribution; D011795:Surveys and Questionnaires
D000928:Antidepressive Agents; D000978:Antiparkinson Agents; D018491:Dopamine Agonists; D008996:Monoamine Oxidase Inhibitors; D007980:Levodopa; D000547:Amantadine