Funding agencies: This study was funded by the Monument Trust Discovery Award from Parkinson's UK, the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre based at Oxford University Hospitals National Health Service (NHS) Trust and University of Oxford, and the Dementias and Neurodegenerative Diseases Research Network (DeNDRoN). The views expressed are those of the author (s) and not necessarily those of the NHS, the NIHR, or the Department of Health.
Predictors of cognitive impairment in an early stage Parkinson's disease cohort
Article first published online: 6 JAN 2014
© 2014 The Authors. International Parkinson and Movement Disorder Society published by Wiley Periodicals, Inc.
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
Volume 29, Issue 3, pages 351–359, March 2014
How to Cite
Hu, M. T. M., Szewczyk-Królikowski, K., Tomlinson, P., Nithi, K., Rolinski, M., Murray, C., Talbot, K., Ebmeier, K. P., Mackay, C. E. and Ben-Shlomo, Y. (2014), Predictors of cognitive impairment in an early stage Parkinson's disease cohort. Mov. Disord., 29: 351–359. doi: 10.1002/mds.25748
Relevant conflicts of interest/financial disclosures: Nothing to report.
Full financial disclosures and author roles may be found in the online version of this article.
- Issue published online: 17 MAR 2014
- Article first published online: 6 JAN 2014
- Manuscript Revised: 18 OCT 2013
- Manuscript Accepted: 18 OCT 2013
- Manuscript Received: 14 MAR 2013
- Parkinson's disease;
- mild cognitive impairment;
- Mini-Mental State Examination;
- Montreal Cognitive Assessment
The impact of Parkinson's disease (PD) dementia is substantial and has major functional and socioeconomic consequences. Early prediction of future cognitive impairment would help target future interventions. The Montreal Cognitive Assessment (MoCA), the Mini-Mental State Examination (MMSE), and fluency tests were administered to 486 patients with PD within 3.5 years of diagnosis, and the results were compared with those from 141 controls correcting for age, sex, and educational years. Eighteen-month longitudinal assessments were performed in 155 patients with PD. The proportion of patients classified with normal cognition, mild cognitive impairment (MCI), and dementia varied considerably, depending on the MoCA and MMSE thresholds used. With the MoCA total score at screening threshold, 47.7%, 40.5%, and 11.7% of patients with PD were classified with normal cognition, MCI, and dementia, respectively; by comparison, 78.7% and 21.3% of controls had normal cognition and MCI, respectively. Cognitive impairment was predicted by lower education, increased age, male sex, and quantitative motor and non-motor (smell, depression, and anxiety) measures. Longitudinal data from 155 patients with PD over 18 months showed significant reductions in MoCA scores, but not in MMSE scores, with 21.3% of patients moving from normal cognition to MCI and 4.5% moving from MCI to dementia, although 13.5% moved from MCI to normal; however, none of the patients with dementia changed their classification. The MoCA may be more sensitive than the MMSE in detecting early baseline and longitudinal cognitive impairment in PD, because it identified 25.8% of those who experienced significant cognitive decline over 18 months. Cognitive decline was associated with worse motor and non-motor features, suggesting that this reflects a faster progressive phenotype. © 2014 International Parkinson and Movement Disorder Society