Prevalence and clinical features of hedonistic homeostatic dysregulation in Parkinson’s disease.

Hedonistic homeostatic dysregulation (HHD) is a neuropsychiatric disorder recently described in Parkinson's disease (PD), which is characterized by self-medication and addiction to dopaminergic drugs. To understand the prevalence of this disorder, we screened 202 PD patients attending our movement disorder unit for HHD. The clinical features of the patients identified as affected by this syndrome were then compared with those of control PD patients in an attempt to ascertain the possible risk factors for HHD. Results showed 7 subjects who fulfilled the HHD criteria. The analysis of a case–control study showed a significant correlation between HHD and a previous history of mood disorders, and the use of dopamine agonists, either in monotherapy or in combination. The prevalence of HHD in our study is similar to the one reported in the United Kingdom by the authors who first described this syndrome in PD. Of interest, our patients showed a somewhat different pattern of the disorder, suggesting that cultural and environmental factors may play a role in the phenomenology of HHD. © 2004 Movement Disorder Society