Impact of the COVID-19 pandemic on cognitive function in Japanese community-dwelling older adults in a class for preventing cognitive decline

Abstract

We examined the effects of lifestyle and thoughts on cognitive function and change in cognitive function due to restrictions in daily life during the coronavirus disease 2019 (COVID-19) pandemic in community-dwelling older adults with mild cognitive decline. This was a retrospective case-control study. The participants were 88 older adults with mild cognitive decline who participated in a class designed to help prevent cognitive decline. The class was suspended from early-March to end of May 2020 to prevent the spread of COVID-19, and resumed in June 2020. We collected demographic and cognitive function test data (Touch Panel-type Dementia Assessment Scale [TDAS]) before and after class suspension and questionnaire data on their lifestyle and thoughts during the suspension. Change in TDAS scores from before and after the suspension was used to divide the participants into decline (2 or more points worsening) and non-decline (all other participants) groups, with 16 (18.2%) and 72 (81.8%) participants in each group, respectively. A logistic regression model showed that the odds ratio (OR) for cognitive decline was lower in participants whose responses were “engaged in hobbies” (OR = 0.07, p = 0.015), “worked on a worksheet about cognitive training provided by the town hall” (OR = 0.19, p = 0.026), and “had conversations over the phone” (OR = 0.28, p = 0.0495). There was a significant improvement in TDAS scores after class was resumed (p < 0.01). A proactive approach to intellectual activities and social ties may be important for the prevention of cognitive decline during periods of restrictions due to COVID-19. We found that cognitive function test scores before class suspension significantly improved after resuming classes. We speculate that continued participation in the class led to positive behavioral changes in daily life during periods of restriction due to COVID-19.

Age-related cognitive effects of the COVID-19 pandemic restrictions and associated mental health changes in Germans

“…An analysis of the progression of Mini-Mental-State scores in the period before the restrictions of the first pandemic wave and within that wave revealed an acceleration of cognitive decline in a sample of cognitively impaired individuals 65 . A similar effect was demonstrated in people in prodromal phases like mild cognitive impairment 66 , although these effects varied on an individual level since participants who engaged in leisure time activities, talked to others on the phone or conducted cognitive training at home showed lower cognitive decline. Such activities are associated with establishing a strong cognitive reserve, which is protective against neurodegenerative diseases 67 – 71 .…”

“…First, no appropriate baseline data without influences of COVID-19 was available for comparison, which is a relatively common issue in COVID-19 research due to the quick series of events making it difficult to conduct studies in a timely manner and it has been reported in other studies, as well (e.g. 20 , 66 ). Yet, we assumed that due to the close proximity of the first assessment to the start of the first lockdown, there should not be a considerable impact on subjective and objective cognitive functioning or on depressiveness and loneliness.…”

Cognitive and balance performance of older adult women during COVID-19 pandemic quarantine: an ex post facto study

“…Consistent with the present study, Kouzuki et al . examined the effect of quarantine associated with COVID-19 by conducting phone interviews with the caregivers of 31 older people with mild cognitive impairment (MCI) and found that cognitive function declined in 41% of the participants [ 33 ]. Furthermore, investigations have shown that self-quarantine during the COVID-19 pandemic caused social isolation and reduced individual activities, and increased the risk of cognitive decline in the older adults [ 34 , 35 ].…”