In the follow-ups, self-reported information on participation in intellectual pursuits within a month before assessment was collected.
Examples of intellectual activities were reading books, newspapers, or magazines; playing board games, Mahjong, or card games; and betting on horse racing.
Among the 15,582 individuals, 1349 (8.7%) developed dementia during a median follow-up period of five years.
“We found that late-life participation in intellectual activities was associated with lower risk of incident dementia several years later.
“This association was not fully explained by other health lifestyle practices (regular physical exercise, adequate fruit and vegetable intake, and not smoking) nor by a wide range of physical health problems and limitations (cardiovascular risk factors, depression, sensory impairments, and poor mobility).
“These findings suggest that active participation in intellectual activities can reduce the risk of, or delay the onset of, dementia.”
They found that not all types of leisure activities were associated with decreased risk of dementia.
In particular, they did not find an association between social or recreational activities and lower risk of dementia.
“It may be that, given the very high level of participation in recreational and social activities in our cohort, a ceiling effect might mask any association with risk of dementia,” they said.
“However, as these activities are in general more passive and less cognitively demanding than intellectual activities, we speculate that recreational and social activities might not be as effective as intellectual activities in preventing dementia.”
Given the growing older population worldwide, promoting regular engagement in intellectual activities might help delay or prevent dementia, they said.
Lee ATC, Richards M, Chan WC, Chiu HFK, Lee RSY, Lam LCW. Association of Daily Intellectual Activities With Lower Risk of Incident Dementia Among Older Chinese Adults. JAMA Psychiatry. Published online May 30, 2018. doi:10.1001/jamapsychiatry.2018.0657
The study can be read here.