MCI-PD
Criteria for the diagnosis of MCI-PD is comprised of the following: established diagnosis of PD; a subjective complaint of cognitive change by the patient; gradual decline (versus acute or sudden); and cognitive deficits in either neuropsychologic testing or global testing that do not interfere with function. Scales acceptable according to MDS for diagnosis of MCI-PD include the Montreal Cognitive Assessment Performance (MoCA), Parkinson's Disease–Cognitive Rating Scale, Scales for Outcomes of Parkinson's Disease–Cognition, and the Mattis Dementia Rating Scale (Table). It is important to note that, although the MMSE is the only recommended test for use in diagnosing PDD, is not an appropriate test to use in the MCI-PD population. The MMSE places emphasis on memory and orientation and contains few questions testing executive function. In 1 study, which included 106 participants, Mamikonyan et al. found that one third of the patients who had been previously diagnosed with MCI-PD had normal scores on the MMSE. If a provider is unsure of the diagnosis, a neurology consult may be useful so that a battery of neuropsychiatric testing can be done and each cognitive domain can be thoroughly assessed (Box 2).