There are over 400,000 Australians living with dementia and this number is estimated to grow to over half a million by 2025.
Dementia is a leading cause of death and reduced quality of life. While there are some risk factors for dementia that can’t be directly modified – like gender, age and genetic profile – modifiable lifestyle and social factors have been identified that may assist in reducing risk, or delaying onset, of dementia.
These include good diet, exercise, social engagement, limiting alcohol intake and not smoking. The concept of cognitive reserve has also been proposed to account for differences in cognitive health and rates of cognitive decline.
Cognitive reserve describes the brain’s ability to optimise performance through engagement in mental activities like education and complex occupations. Cognitive reserve is thought to provide the brain with greater resilience to fight the effects of cognitive decline. Lifestyle factors may reduce risk of cognitive decline by contributing to the cognitive reserve.
Researchers looked at the potential mediating effect of cognitive reserve – defined by educational level and occupational complexity – on the association between lifestyle factors and cognitive function. Study participants were adults aged 65 years and over.
Cognitive function and reserve were assessed and lifestyle factors measured including exercise levels, smoking status, alcohol consumption and dietary patterns. Engagement in cognitive and social activity – like listening to the radio, reading, playing games like cards or chess, and doing crosswords and puzzles – was also recorded.
All lifestyle factors aside from smoking were significantly associated with cognitive function in older adults (smoking has, however, been found in other studies to be associated with cognitive decline). Cognitive reserve was found to mediate the association between modifiable lifestyle factors and cognitive function.
The findings of this study support the recommendation to engage in mentally stimulating activities early in life and to continue these throughout the life course.
It also speaks to the benefits of a healthy lifestyle with plenty of exercise, a nutritious diet, minimal alcohol consumption as well as undertaking complex cognitive and social activities.