Mild cognitive impairment in patients with Parkinson´s disease and the analysis of associated factors

ABSTRACT

Objectives

This research targeted to understand the impact of clinical findings, non-motor symptoms, white matter hyperintensities (WMHs), and metabolic features on cognition in Parkinson’s disease patients with mild cognitive impairment (PD-MCI).

Methods

Sixty-one PD patients sundered into two groups: PD-MCI and normal cognition (PD-NC). We assessed cognition using Montreal Cognitive Assessment-TR (MoCA-TR) and Frontal Assessment Battery (FAB). We used the modified Hoehn&Yahr staging scale (mH&Y), Unified Parkinson’s Disease Rating Scale (UPDRS), Freezing of Gait questionnaire, Beck Depression Inventory, Parkinson’s disease sleep scale-2, Pittsburgh sleep quality index, Epworth sleepiness scale, and Non-motor symptoms questionnaire to evaluate all patients. We used the Fazekas scale to evaluate the WMHs and also investigated all laboratory parameters affecting cognitive functions.

Results

Duration of disease, UPDRS-Motor part, age, disease stage, and daytime sleepiness were dramatically higher in the PD-MCI group than in PD-NC (p < 0.05). WMHs and homocysteine were higher in the PD-MCI group than in the controls (p = 0.016 and p < 0.001, respectively). There was a negative correlation between cognition and duration of disease, age, disease stage, UPDRS-Motor scale, daytime drowsiness, WMHs and homocysteine levels. Homocysteine was negatively related to visuospatial/executive functions (r=-0.303, p = 0.021). WMHs were correlated with global cognition (p =.000 r = .-542), language (p = .001, r = -.434), and delayed recall (p = .011, r = -.332).

Discussion

Mild cognitive impairment is a widespread clinical situation of PD patients and often presents before the motor symptoms. Revealing curable causes that affect cognition before the development of PD-related dementia is crucial in controlling motor findings and reducing the burden of the caretakers.

KEYWORDS:

• Mild cognitive impairment
• Parkinson’s disease
• dementıa
• homocysteıne
• whıte matter hyperıntensıtıes

Disclosure statement

The authors have no conflicts of interest to declare.

Author contributions

Esma Kobak Tur intended and designed the study, performed the statistical analysis, and wrote the manuscript. Buse Cagla Ari was involved in writing, conceived, and supervised the work. All of the authors discussed the results, reviewed and are responsible for the manuscript.

Ethical considerations

The research has approval of the Local Ethics Committee of Fatih Sultan Mehmet Research and Training Hospital.

Consent to participate

An informed consent form was signed by all the patients.

Consent for publication

We further confirm that the content has not been published or submitted for publication elsewhere. It was presented as a poster at ‘’World Congress On Parkinsonʼs Disease and Related Disorders 2020’ and published as a brief abstract at Parkinsonism & Related Disorders in October 2020.

Additional information

Funding

This research did not receive any specific grant from funding agencies in the public, profit, or not-for-profit sectors. The study was performed in the Departments of Neurology, Fatih Sultan Mehmet Research and Training Hospital.