© Cambridge University Press 2013. Cognitive evaluation is an essential component of the management process involving patients with Parkinson’s disease (PD). Formal neuropsychological examination is required to ascertain the degree and pattern of cognitive impairment (CI) over the course of PD and to evaluate patients in therapeutic trials. The purpose of this chapter is to guide clinicians to choose the length and depth of the cognitive evaluation from a non-exhaustive list of pertinent instruments. Emphasis is placed on changing concepts and confounding factors relative to the heterogeneous profile of CI from early PD to Parkinson’s disease dementia (PDD) and the emerging construct of mild cognitive impairment (PD-MCI). PD has historically been characterized by the occurrence of clinically meaningful motor features such as resting tremor, bradykinesia, or postural instability . However, during the last decade, compelling evidence has proved that CI is pervasive in PD [2,3]. It can be identified as relatively subtle cognitive defects present in more than 30% of patients at the time of diagnosis of PD , using a common definition for defining MCI in more than 25% of subjects in large transversal samples , or accomplishing criteria for PDD in at least 30% of PD subjects . Thus, PD on its own constitutes an important risk factor for the development of dementia, with a risk 4-6 times greater than in subjects without PD . Nevertheless, the exact etiology of PDD has not yet been clarified, and it is highly variable in occurrence, sometimes occurring earlier with a fast progression and other times appearing more than 10 years after diagnosis [3,5-7].
|Title of host publication||Neuropsychiatric and Cognitive Changes in Parkinson's Disease and Related Movement Disorders: Diagnosis and Management|
|Number of pages||11|
|Publication status||Published - 1 Jan 2010|