Cognitive function in people with and without freezing of gait in Parkinson’s disease

Abstract

Freezing of gait (FOG) is common in people with Parkinson's disease (PD) which is extremely debilitating. One hypothesis for the cause of FOG episodes is impaired cognitive control, however, this is still in debate in the literature. We aimed to assess a comprehensive range of cognitive tests in older adults and people with Parkinson's with and without FOG and associate FOG severity with cognitive performance. A total of 227 participants took part in the study which included 80 healthy older adults, 81 people with PD who did not have FOG and 66 people with PD and FOG. A comprehensive battery of neuropsychological assessments tested cognitive domains of global cognition, executive function/attention, working memory, and visuospatial function. The severity of FOG was assessed using the new FOG questionnaire and an objective FOG severity score. Cognitive performance was compared between groups using an ANCOVA adjusting for age, gender, years of education and disease severity. Correlations between cognitive performance and FOG severity were analyzed using partial correlations. Cognitive differences were observed between older adults and PD for domains of global cognition, executive function/attention, and working memory. Between those with and without FOG, there were differences for global cognition and executive function/attention, but these differences disappeared when adjusting for covariates. There were no associations between FOG severity and cognitive performance. This study identified no significant difference in cognition between those with and without FOG when adjusting for covariates, particularly disease severity. This may demonstrate that complex rehabilitation programs may be undertaken in those with FOG.

Comparing the Clinical and Neuropsychological Characteristics of Parkinson’s Disease With and Without Freezing of Gait

“…When comparing PD patients with the HC group, PD patients showed poorer cognitive function, higher risks of depression and anxiety, and more neuropsychiatric symptoms. These results were consistent with general clinical observations and previous studies ( Morrist et al, 2020 ). When comparing PD-FOG(+) patients with PD-FOG(−) patients, no differences were seen in cognitive function, but significant differences could be seen in neuropsychiatric and clinical symptoms.…”

“…FOG is one of the most common walking problems in advanced Parkinson’s disease (PD) ( Ortelli et al, 2019 ). It not only increases patients’ risk of falls and injuries, but also leads to emotional disorders and poor quality of life ( Morrist et al, 2020 ; Rahimpour et al, 2020 ). Although some pharmacological and physical interventions are used to alleviate FOG in PD patients, the results are still far from satisfactory ( Onder and Ozyurek, 2020 ).…”

“…But, in most of these studies, motor symptoms of PD-FOG(+) patients are significantly more severe than that of PD-FOG(−) patients, which puts PD-FOG(+) patients at a natural disadvantage. What is more, a recent study involving 227 participants suggests that the severity of FOG may not synchronize with the severity of CI, indicating that motor function discrepancy may affect the results of neuropsychological tests ( Morrist et al, 2020 ). Functional imaging studies also found that the mechanism of FOG is related to advanced cognitive and attention-related networks rather than motor networks ( Li Y. et al, 2020 ).…”

Validation of the German Version of the New Freezing of Gait Questionnaire for People with Parkinson‘s Disease

“…It was also correlated with the TUG while performing an additional cognitive task but not with the MoCA. These rather inconsistent results reflect current findings about the association between FOG and cognition as some studies support this association [ 24 – 26 ] whereas others do not [ 27 ]. The fact that the NFOG-Q was not correlated with the MoCA but with the dual-tasking TUG might reflect that FOG is less related to global cognition [ 27 ] than to specific cognitive impairments such as dual tasking.…”

“…These rather inconsistent results reflect current findings about the association between FOG and cognition as some studies support this association [ 24 – 26 ] whereas others do not [ 27 ]. The fact that the NFOG-Q was not correlated with the MoCA but with the dual-tasking TUG might reflect that FOG is less related to global cognition [ 27 ] than to specific cognitive impairments such as dual tasking. The impaired simultaneous conduction of a cognitive and motor task might represent increased cognitive control (due to reduced automaticity) in PD + FOG when performing motor tasks, reducing cognitive resources for the cognitive task.…”