Nearly half of people with Parkinson’s disease who take levodopa or a dopamine agonist for their condition develop impulse-control disorders. Common compulsive behavior disorders include sex addiction, substance abuse, and compulsive eating, gambling, and shopping.
Dopamine is a neurotransmitter in the brain that plays a key role in learning and is released when we experience pleasure. Dopamine deficiency is a hallmark of Parkinson’s. Some previous studies showed a connection between drugs used to treat Parkinson’s and impulse control disorders, while other studies did not.
For this latest study, researchers at the ICM Brain and Spine Institutel in Paris used a larger cohort and a longer follow-up period – at least three years – to provide more reliable results. The study involved 411 people diagnosed with Parkinson's within a five-year span, 356 of whom had taken a dopamine agonist, and 81 of whom reported compulsive behavior.
The researchers found that 94 of the 306 participants who did not report having impulse-control problems at baseline developed compulsive behavior during the study, which amounts to about 46 percent over five years. In those who had never taken a dopamine agonist, the five-year incidence of impulse control disorders was just 12 percent. Additionally, in the 30 participants with impulse control disorders who stopped taking the drugs, the compulsive behaviors stopped.
Sourced from: Neurology