Gambling, Pathologic

Description

Pathologic gambling is defined as a chronic and progressive failure to resist impulses to gamble accompanied by gambling behavior that compromises or damages personal, family, or vocational pursuits. The prevalence of pathologic gambling in the adult American population is estimated to be between 1 and 3% (review by Eisen et al., 1998).

Comings et al. (2001) noted that some form of gambling is legal in all but 2 states in the U.S., and gambling on the Internet is available to anyone with a computer regardless of the local laws. They stated that as access to gambling has increased, there has been a corresponding increase in the frequency of addiction to gambling, known as pathologic gambling.

Inheritance

Eisen et al. (1997, 1998) studied 3,359 mono- and dizygotic U.S. male twin pairs who had served in the military and found that inherited factors explained between 37 and 55% of the prevalence of 5 individual symptoms of pathologic gambling (attempts to wind back losses at same place, gambling larger amounts than intended, repeated efforts to reduce or stop gambling, frequent preoccupation with gambling, and increase betting to maintain interest) from DSM-III-R for which data was informative. In addition, inherited factors plus shared environmental experiences explained 56% of the report of 3 or more symptoms of pathologic gambling and 62% of the diagnosis of pathologic gambling disorder (4 or more symptoms).

Pathogenesis

A number of different neurotransmitters have been thought to be implicated in pathologic gambling. Comings et al. (2001) studied polymorphisms at 31 different genes involved in dopamine, serotonin, norepinephrine, GABA, and other types of metabolism in 139 pathologic gamblers and 139 age, race, and sex-matched controls. Fifteen genes were included in the multivariate regression analysis. The most significant were DRD2 (126450), DRD4 (126452), DAT/DAT1 (SLC6A3; 126455), TPH (191060), ADRA2C (104250), NMDAR1 (138249), and PS1 (104311) genes. Dopamine, serotonin, and norepinephrine genes contributed approximately equally to the risk of pathologic gambling. The results indicated that genes influencing a range of brain functions play an additive role as risk factors for pathologic gambling. Comings et al. (2001) suggested that multigene profiles in specific individuals may help in choosing appropriate treatment.

Tippmann-Peikert et al. (2007) reported 3 patients with restless legs syndrome (RLS; 102300) who developed pathologic gambling after treatment with dopamine agonists. The behavior was dose-dependent, and there were no other compulsive behaviors. Pathologic gambling resolved in all 3 patients after discontinuation of the medication. In 1 patient, treatment with gabapentin led to resolution of RLS symptoms without side effects.

Voon et al. (2007) evaluated 21 patients with Parkinson disease (PD; 168600) who developed pathologic gambling after receiving pharmacologic treatment with dopaminergic agonists. Compared to 42 PD patients without compulsive behaviors, those who developed pathologic gambling had a younger age at PD onset, higher novelty seeking (601696), tended to have medication-induced hypomania or mania, impaired planning, and a personal or family history of alcohol use disorders (see 103780).