Assessment of hyper- and hypodopaminergic behaviors in Parkinson's disease

The common perception that Parkinson's disease patients tend to be depressed, anxious, apathetic and harm-avoiding has currently been challenged by the recognition that they can also exhibit a hedonistic, novelty-seeking personality. Thus, Parkinson's disease patients may indulge in their passions in an irresponsible and disinhibited manner, and engage in repetitive, compulsive behaviors that may be harmful and destructive to their social or professional lives. The dopamine dysregulation syndrome includes hypersexuality, pathological gambling, and compulsive shopping; it is associated with addiction to dopaminergic medication. However, not all behavioral changes are necessarily accompanied by a dopaminergic addiction. After antiparkinson treatment is initiated, patients enter a 'honeymoon period' during which changes in mood and behavior reflect a return to the patients' premorbid personality. The increased motivation and higher level of activity in professional as well as leisure activities are considered positive changes by both the patients and their relatives. With prolonged and increased dopaminergic treatment, these positive behavioral changes can become excessive and evolve into nocturnal hyperactivity and stereotyped, repetitive and time consuming behaviors which ultimately disorganize the patient's everyday routine and herald behavioral addictions. These drug-induced behavioral changes are under-appreciated by neurologists and under-reported by the patients who neither complain about the behaviors nor understand the relationship between motivated behavior and dopaminergic medication. For these reasons, we propose a new scale for the assessment of behavior and mood to quantify and track changes related to Parkinson's disease, to dopaminergic medication, and to non-motor fluctuations. This scale is based on the concept of hypo- and hyperdopaminergic mood and behavior. The scale consists of 18 items addressing non-motor symptoms, grouped in four parts: general psychological evaluation, apathy, non-motor fluctuations and hyperdopaminergic behaviors. The rating in five points (0-4 from absent to severe) is carried out during a semi-structured interview. Open-ended questions introduce each item, allowing patients to express themselves as freely as possible. Close-ended questions permit the rating of severity and intensity. This new instrument can be used by psychologists, psychiatrists or neurologists familiar with Parkinson's disease. Designed to detect changes in mood and behavior of Parkinson's disease patients resulting either from the disease or its treatment, this tool can be used in conjunction with the neurocognitive evaluation, to help tailor the treatment of motor and non-motor symptoms to each individual's needs. (C) 2009 Elsevier Masson SAS. All rights reserved.