Cognitive impairment in Parkinson's disease

Leiden University, Leyden, South Holland, Netherlands
Journal of neurology, neurosurgery, and psychiatry (Impact Factor: 6.81). 12/2007; 78(11):1182-7. DOI: 10.1136/jnnp.2006.112367
Source: PubMed


Cognitive impairment plays a role in Parkinson's disease (PD) and has important consequences for patient management. However, many aspects of cognitive impairment in PD remain unclear because of the use of different and often invalid measurement instruments. In this study, a reliable and valid instrument, the SCales for Outcomes in PArkinson's disease-COGnition (SCOPA-COG), was used.
To evaluate cognitive functioning in a large cohort of patients with Parkinson's disease and to assess the relations with demographic, disease related and clinical variables.
A cohort of 400 patients with PD was evaluated for cognition, motor and non-motor domains, as well as for demographic and disease related characteristics. Results were compared with 150 controls matched for overall age, sex and education distribution.
Patients with PD scored significantly lower on all cognitive subdomains compared with controls, with the largest differences for executive functioning and memory. After correction for age and years of education, 22% of patients had impaired cognition, as measured by the total SCOPA-COG score, compared with controls. Across all patients, more severe cognitive impairment was associated with significantly more impairment in motor, autonomic, depressive and psychotic domains. Patients with the postural instability gait difficulty (PIGD) dominant phenotype showed more cognitive impairment compared with patients with the tremor dominant phenotype. Contrary to tremor scores, PIGD scores significantly worsened with increasing disease severity.
Cognition is an important domain of the clinical spectrum of PD and poorer cognitive performance is associated with greater impairment in motor and non-motor domains in PD. The difference in cognitive scores between PIGD dominant patients and tremor dominant patients likely reflects more advanced disease.

Download full-text


Available from: Martine Jeukens-Visser
  • Source
    • "In longitudinal studies, individuals with PIGD-dominant or mixed PIGD-tremor phenotypes were more likely than those with tremor-dominant phenotype to develop global cognitive decline and dementia [8] [14]. In cross-sectional studies, the PIGD-dominant phenotype was more common in those demonstrating poorer performance on measures of global cognitive function (Scales for Outcomes in Parkinson's Disease- Cognition) [6] and in those with PD-D [15]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Research suggests an association between global cognition and postural instability/gait disturbance (PIGD) in Parkinson disease (PD), but the relationship between specific cognitive domains and PIGD symptoms is not clear. This study examined the association of cognition (global and specific cognitive domains) with PIGD symptoms in a large, well-characterized sample of individuals with PD. Cognitive function was measured with a detailed neuropsychological assessment, including global cognition, executive function, memory, visuospatial function, and language. PIGD symptoms were measured using the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III, Motor Examination subscale. Multiple linear regression analyses were performed to assess the relationship between cognition and PIGD symptoms with models adjusting for age, sex, education, enrollment site, disease duration, and motor symptom severity. The analysis included 783 participants, with mean (standard deviation) age of 67.3 (9.7) years and median (interquartile range) MDS-UPDRS Motor Subscale score of 26 (17, 35). Deficits in global cognition, executive function, memory, and phonemic fluency were associated with more severe PIGD symptoms. Deficits in executive function were associated with impairments in gait, freezing, and postural stability, while visuospatial impairments were associated only with more severe freezing, and poorer memory function was associated only with greater postural instability. While impairments in global cognition and aspects of executive functioning were associated with more severe PIGD symptoms, specific cognitive domains were differentially related to distinct PIGD components, suggesting the presence of multiple neural pathways contributing to associations between cognition and PIGD symptoms in persons with PD. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Full-text · Article · Apr 2015 · Parkinsonism & Related Disorders
  • Source
    • "Parkinson's disease (PD) is traditionally characterized by motor symptoms such as bradykinesia, rigidity, tremors and postural instability. Many PD patients may also present cognitive symptoms including executive dysfunctions (e.g., working memory, mental flexibility and inhibition deficits) (Owen et al., 1992; Verbaan et al., 2007) and language impairments (e.g., verbal fluency and pragmatic deficits) (Monetta, Grindod, & Pell, 2009; Murray, 2008; Pell & Monetta, 2008; Vachon-Joannette, Tremblay, Langlois, Chantal, & Monetta, 2013). Pragmatic language such as metaphor comprehension is often impaired in PD, probably because it requires high-level language and cognitive abilities (McKinlay, Dalrymple-Alford, Grace, & Roger, 2009; Monetta & Pell, 2007). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The effects of subthalamic nucleus (STN) deep brain stimulation (DBS) in Parkinson’s disease (PD) on different language abilities are still controversial and its impact on high-level language abilities such as metaphor comprehension has been overlooked. The aim of this study was to determine the effects of STN electrical stimulation on metaphor comprehension and language abilities such as lexical and semantic capacities. Eight PD individuals with bilateral STN-DBS were first evaluated OFF-DBS and, at least seven weeks later, ON-DBS. Performance on metaphor comprehension, lexical decision, word association and verbal fluency tasks were compared ON and OFF-DBS in addition to motor symptoms evaluation. STN stimulation had a significant beneficial effect on motor symptoms in PD. However, this stimulation did not have any effect on metaphor comprehension or any other cognitive ability evaluated in this study. These outcomes suggest that STN stimulation may have dissociable effects on motor and language functions.
    Full-text · Article · Feb 2015 · Brain and Language
  • Source
    • "For example, three participants who recalled falling at least monthly had no recent falls in their notes, and four had only a single fall recorded; five people without a MMSE in their notes had a MoCA suggesting moderate CI. Though using the MMSE and the MoCA to evaluate CI may have contributed to the differences in the rates and severity of CI noted in different parts of the current study, we agree with others [28] [29] who suspect MMSE underestimates the degree of cognitive dysfunction in PD. "
    [Show abstract] [Hide abstract]
    ABSTRACT: We compared fall frequency and prediction among People with Parkinson's Disease (PwP) with and without cognitive impairment (CI); researchers sometimes overlook the former, concerned about consent, recall and adherence and differences in fall frequency and predictability.Methods We recruited 101 PwP from one clinic, used the Montreal Cognitive Assessment to measure CI, noted repeated falls recalled retrospectively over 12 months and evaluated ‘repeated falls’ and ‘difficulty turning’ as predictors of falls over three months.ResultsParticipant median age was 76 years, and time since diagnosis 6 years. Of 40 participants without CI, 40% recalled falls and 55% fell during follow-up (1.9 (±3.8) falls/person), the sensitivity of fall history being 57% and of turning 36%. Of 36 participants with mild CI, 42% recalled falls and 42% fell during follow-up (1.2 (±1.8) falls/person), the sensitivity of fall history being 67% and of turning 69%. Of 25 participants with moderate CI, 60% recalled falls and 58% fell during follow-up (1.2 (±1.8) falls/person), the sensitivity of fall history being 71% and of turning 69%.Conclusions Researchers need not exclude people with CI assuming falls are more frequent and less predictable than among those without. Fall rates (falls/person during follow-up) were similar among people with and without CI. Falls and difficulty turning were more sensitive predictors of falling in those with CI than those without: a simple mobility test may suggest an individual's risk of falling if a history is unavailable. Most PwP with moderate CI fall repeatedly: carer involvement facilitates their inclusion in research.
    Full-text · Article · Nov 2014 · Parkinsonism & Related Disorders
Show more