Pathological gambling in Parkinson's disease: what are the risk factors and what is the role of impulsivity?

Abstract

The incidence of pathological gambling in Parkinson's patients is significantly greater than in the general population. A correlation has been observed between dopamine agonist medication and the development of pathological gambling. However, scientists conjecture that the affected patients have underlying risk factors. Studies analysing Parkinson's patients have detected that patients who developed pathological gambling are younger, score higher on novelty-seeking tests, are more impulsive and are more likely to have a personal or family history of alcohol addiction. In addition, some genetic variations have been associated with the susceptibility of developing pathological gambling, which include mutations of DRD3, 5-HTTLPR and GRIN2B. Studies focusing on neurofunctional discrepancies between Parkinson's patients with and without pathological gambling have found increased functional activation and dopamine release in regions associated with the mesolimbic reward system. Furthermore, there is also evidence showing increased processing of reward and decreased activation elicited by punishment, suggesting altered learning processes. Furthermore, the role of deep brain stimulation of the nucleus subthalamicus (STN DBS) is controversial. In most Parkinson's patients, pathological gambling resolved after the initiation of the STN DBS, which might be explained by discontinuation or decrease in dopamine agonist medication. However, it has been also shown that some patients are more impulsive while the STN DBS is activated. These differences may depend on the DBS localization in the more limbic or motor part of the STN and their regulative effects on impulsivity. Further research is needed to clarify susceptibility factors for the development of pathological gambling in Parkinson's patients.

How Individual Habits Fit/Unfit Social Norms: From the Historical Perspective to a Neurobiological Repositioning of an Unresolved Problem

“…These consequences are also described as correlated with iatrogenic causes: for instance, some pharmacologic treatments of Parkinson's disease may induce gambling, which is related to the altered distribution of dopamine in the above-mentioned areas (Heiden et al, 2017). This alteration determines a strong hedonistic feeling correlated to the habit of gambling which is an integral part of maintaining such a bad habit.…”

Impulse Control Disorders and Related Complications of Parkinson's Disease Therapy

“…Studies of risk factors for ICD suggest that a family history of alcoholism may place a PD individual at risk for this behavior. 79 One biological reason for this is alteration to serotonin levels, as reduced levels of tryptophan, an amino acid necessary for making serotonin, is associated with alcoholism. Individuals with low levels of the serotonin (5-HT) metabolite, HIAA, have greater impulsivity characteristics and early signs of alcoholism.…”

A Revision of the Relationship between Gambling Disorder, Attention Deficit Hyperactivity Disorder and Parkinson´s Disease

“…Finally, a current revision work (Heiden, Heinz, & RomanczukSeiferth, 2017) confirmed the higher comorbidity of gambling disorder in pd patients compared to the general population. Some of the factors that explained this comorbidity were dopamine agonist medication, age (younger), higher scores in novelty seeking and impulsivity scales, history of substance abuse disorder (alcohol), genetic mutations, increased functional activation in the mesolimbic reward system, increased dopamine release in the mesolimbic reward system and distorted learning processes (Heiden et al, 2017).…”

“…On the other hand, other revisions confirmed that the incidence of gambling disorder in pd sufferers was higher than that found in the general population. Some of the factors that explained this tendency were dopamine agonist medication, age (younger), marked novelty seeking and impulsivity, background of alcohol use disorder, diverse genetic mutations (N-methyl D-aspartate receptor subtype 2B, dopamine receptor D3, and serotonin-transporter-linked polymorphic region), augmented functional activation in the mesolimbic reward system, augmented dopamine release in the mesolimbic reward system, and distorted learning processes (Heiden et al, 2017). Other revision (meta-analysis) confirmed that patients with pd following dopamine medication denoted disruption in the Iowa Gambling Task performance compared to controls (Evens, Hoefler, Biber, & Lueken, 2016).…”