Severity of mild cognitive impairment in early Parkinson's disease contributes to poorer quality of life

Research output: Contribution to journalArticle

Abstract

BACKGROUND: Poor quality of life (QoL) is a feature of people with Parkinson's disease (PD) who develop dementia. The relationship between mild cognitive impairment in PD (PD-MCI) and QoL is less clear. To address this, we studied the impact of varying severities of cognitive impairment on QoL in a cohort of non-demented patients with early PD.

METHOD: Patients with newly diagnosed PD (n = 219) and age and sex matched healthy controls (n = 99) completed a schedule of neuropsychological tests, in addition to scales assessing QoL (PDQ-39), depression, sleep, neuropsychiatric symptoms and a clinical examination. The Movement Disorder Society criteria were used to define and classify PD-MCI.

RESULTS: Participants with PD-MCI were significantly older than those with normal cognition, had more severe motor symptoms, scored higher for depression and had poorer quality of life. Logistic regression showed that mild cognitive impairment, independent of other factors, was an indicator of poorer QoL. Using cognitive performance 2.0 standard deviations (SD) below normative data as a cut-off to define PD-MCI, there was a significant difference in QoL scores between patients with PD-MCI and those classified as having normal cognition. Subjects with less severe mild cognitive impairment did not exhibit significant differences in QoL.

CONCLUSIONS: PD-MCI is a significant, independent factor contributing to poorer QoL in patients with newly diagnosed PD. Those classified with greatest impairment (2.0 SD below normal values) have lower QoL. This has implications for clinical practice and future interventions targeting cognitive impairments.

Details

Authors
  • Rachael A Lawson
  • Alison J Yarnall
  • Gordon W Duncan
  • Tien K Khoo
  • David P Breen
  • Roger A Barker
  • Daniel Collerton
  • John-Paul Taylor
  • David J Burn
Organisations
External organisations
  • University of Cambridge
Research areas and keywords

Keywords

  • Aged, Attention, Executive Function, Female, Humans, Male, Memory, Middle Aged, Mild Cognitive Impairment, Neuropsychological Tests, Parkinson Disease, Predictive Value of Tests, Quality of Life, Space Perception, Statistics, Nonparametric, Journal Article, Research Support, Non-U.S. Gov't
Original languageEnglish
Pages (from-to)1071-5
Number of pages5
JournalParkinsonism and Related Disorders
Volume20
Issue number10
Publication statusPublished - 2014 Oct
Publication categoryResearch
Peer-reviewedYes