A review suggests increased levels of leisure activities could lower the risk of all-cause dementia including Alzheimer’s disease
Increased amounts of all types of leisure activities e.g., cognitive, physical and social reduce the risk of developing all-cause dementia (ACD). However, only cognitive and physical activities reduce Alzheimer’s disease (AD) risk and vascular dementia (VD) risk is only significantly reduced through higher physical activity. These were the key findings from a systematic review and meta-analysis by a team of Chinese researchers.
Dementia is a syndrome characterised by a deterioration in cognitive function beyond that which might be expected from the usual consequences of biological ageing and currently, across the globe, affects some 55 million people. Although there are several types of dementia, the most common is Alzheimer’s disease, followed by vascular dementia. Despite available treatments, there is currently no cure for dementia and recommendations to reduce risk factors include switching to a healthy diet and staying mentally and socially active. Indeed, there is some evidence that cognitively stimulating leisure activities may delay the onset of dementia in community-dwelling elders although the value of such activities are uncertain. For example, one study found that neither intellectual nor physical activity lifestyle factors were associated with AD biomarkers with another concluding that physical inactivity was not associated with ACD or AD.
Given the uncertainty over the possible value of different types of leisure activities on ACD, for the present study the Chinese team undertook a systematic review and meta-analysis. They set out to assess the effect of three forms of leisure activities: physical (PA), cognitive (CA) and social (SA). For the purposes of the study, PA was defined as walking, playing sports etc; CA, reading books, writing for pleasure or solving crossword puzzles; and SA, anything which involved communication with others, e.g. attendance at social centres, volunteer work etc. The researchers used regression analysis to determine the relationship between the different leisure activities and ACD and the two main subtypes, adjusting for covariates such as age, gender, education and apolipoprotein E.
Leisure activities and all-cause dementia
The literature review identified a total of 38 eligible studies with 215,818 participants and a mean age of 45 years at baseline.
Overall, 36 studies were used to investigate the relationship between the different activities and all-cause dementia. The analysis revealed that participation in leisure activities, compared to no participation, was associated with a 17% lower risk of developing ACD (relative risk, RR = 0.83, 95% CI 0.80 – 0.87, p < 0.001). In subgroup analysis, there was also a significant reduction for each of the different forms of activity, e.g., the relative risk for CA was 0.77 (95% CI 0.68 – 0.87).
For AD, there was an overall 18% lower risk for those participating in leisure activities (RR = 0.82, 95% CI 0.74 – 0.90, p < 0.001) and again, while there was lower and significant risk reduction for PA and CA, it was non-significant for SA (RR = 0.89, 95% CI 0.63 – 1.26) although the latter activity only assessed in a single study.
For vascular dementia, the overall reduction was even greater at 32% (RR = 0.68, 95% CI 0.54 – 0.86, p = 0.007). However, this association was only significant for PA and not for CA, although no studies had examined the relationship with SA.
The authors concluded that leisure activities including physical, cognitive and social, were all significantly associated with a reduced risk of incident dementia and that both PA and CA were linked to a lower risk of AD.
Citation
Su S et al. Leisure Activities and the Risk of Dementia: A Systematic Review and Meta-Analysis Neurology 2022