Even though no comprehensive neuropsychological evaluation was used to establish the cognitive state of the participants, this suggests that these items did not add additional information to the determination of the overall cognitive status of the PD patients. including 304 PD patients, three MoCA subtests did not discriminate between patients with low, middle, and high MoCA total scores: The target tapping task, the naming task, and the orientation task. Previous research already indicated that the MoCA subtests may differ substantially in their respective diagnostic values. This leads to the fact that, for example, the verbal fluency task, although known to be very sensitive in PD patients, receives only 1 point (and thus represents only 1/30 th of the total score), while, for example, the language items “naming”–a function that is by far less frequently affected in PD-constitute 3/30 th of the total score. Rather, it is based on the raw scores of the subtests which are simply summed up to a total score of 30 points. However, it is striking that its scoring procedure is not based on the discriminant power of the individual subtests. The combination of subtests can be regarded as a strength of the MoCA, as a broad range of cognitive domains is covered and assessed with established test paradigms, including very sensitive tasks for the evaluation of executive dysfunction which is of special relevance in PD. The MoCA has also been shown to be suitable to differentiate PD patients with different cognitive states (with no cognitive impairment, mild cognitive impairment, or dementia) from healthy controls. Its sensitivity has consistently been proven to be higher than that of the Mini Mental State Examination (MMSE), especially for detecting milder cognitive symptoms. The Montreal Cognitive Assessment (MoCA) is a widely used tool that has also been recognized to be efficient in detecting cognitive symptoms in PD patients. Thus, for an optimal management of PD patients, early detection of cognitive symptoms in clinical practice is of utmost importance.Ĭognitive screening tests are time-economic and efficient tools to detect cognitive symptoms and dementia and can represent the initial step in a process of clinical decision-making. Mild Cognitive Impairment (MCI) affects about 27% of non-demented PD patients (PD-MCI), and about 30% of PD patients develop Parkinson’s disease dementia (PD-D).

Already 20% of unmedicated de-novo PD patients have cognitive symptoms. They are highly relevant, as they limit the patients’ quality of life, increase caregiver burden, are an important indication for institutionalization, and are related to disease prognosis and mortality. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.ĭata Availability: All relevant data are within the paper and its Supporting Information files.įunding: This study was in part supported by the German Ministry for Education and Research (BMBF Bundesministerium für Bildung und Forschung LANDSCAPE study project-nr: 01GI1008c).Ĭompeting interests: The authors have declared that no competing interests exist.Ĭognitive dysfunction is frequent in patients with Parkinson’s disease (PD).

Received: OctoAccepted: JPublished: July 20, 2016Ĭopyright: © 2016 Fengler et al. PLoS ONE 11(7):Įditor: Ornit Chiba-Falek, Duke University, UNITED STATES (2016) Screening for Cognitive Impairment in Parkinson's Disease: Improving the Diagnostic Utility of the MoCA through Subtest Weighting. Citation: Fengler S, Kessler J, Timmermann L, Zapf A, Elben S, Wojtecki L, et al.

Moca test score 20