A pilot study of impulsivity and compulsivity in pathological gambling.

We examined the relationship between gambling severity, impulsivity and obsessionality/compulsivity in 38 pathological gamblers, representing the complete Minnesota sample of a randomized, placebo-controlled clinical trial of paroxetine for the treatment of pathological gambling (PG), using Pearson correlations and linear regression models at baseline and treatment endpoint. At baseline, Pathological Gambling Modification of the Yale-Brown Obsessive-Compulsive Scale (PG-YBOCS) scores correlated significantly with those of the Eysenck Impulsiveness Questionnaire (EIQ) Impulsiveness subscale and Padua Inventory (PI) factors I and IV (corresponding to impaired control over mental and motor activities, respectively). None of the associations between PI factors and the PG-YBOCS were significant after adjusting for Impulsiveness scores. There were no differences in changes in the PG-YBOCS between the paroxetine and placebo group. Changes in PG-YBOCS scores after treatment correlated with changes in Impulsiveness scores. These changes appeared independent of paroxetine treatment. The results suggest that, although PG exhibits features of both obsessionality/compulsivity and impulsivity and elements of both decrease with treatment, impulsivity predominates and changes in gambling severity are most associated with changes in impulsivity.