25 Feb 2015
By now it is well established that poor cardiovascular and cognitive health in early life can increase the risk of dementia in old age. But did you know that it could also bring forward the age of dementia onset to midlife? Evidence is emerging to suggest that fitness as early as the teenage years could be associated with younger onset dementia (YOD).
Younger onset dementia is any dementia with onset before the age of 65 years. It is much less common than dementia in old age, but there are currently around 20 000 people with YOD living in Australia. Dementia in midlife can be very distressing, especially for those who have young children, a career, elderly parents and financial commitments. Despite this, little is known about what causes dementia at such a young age.
In a recently published study, Swedish researchers assessed the medical records of over one million men in an effort to determine the role of modifiable factors in the epidemiology of YOD1. Each man completed a cycle ergometer test in late adolescence, and their maximum exertion indicated whether they were of low, moderate or high physical fitness. Up to 41 years later, the researchers found that the most physically fit had nearly half the risk of YOD than the least physically fit. Cognitive activity, like education, learning a new language, socialising, ‘brain games’, reading or writing, were also beneficial. The most educated and cognitively active participants at age 18 were nearly 4-times less likely to develop YOD than the least active. Put together, the combination of high cognitive and physical fitness was hugely beneficial, reducing the risk of YOD by more than 7-times.
Although it is unclear whether a similar pattern exists for women, we can learn from these interesting results. They suggest that physical and cognitive activity may not only reduce the risk of dementia in late life, but may delay the onset from midlife when responsibilities are high and future plans could be disrupted. What’s more, they tell us that it is never too early to adopt healthy habits. Looking after our bodies and brains even in childhood and adolescence can have enormous benefits decades later.
It is recommended that children and adolescents should spend at least 60 minutes every day doing moderate to vigorous intensity physical activity. And, it is important to keep this activity going as we grow up – adults are also recommended to do at least two and a half hours of moderate exercise per week. This could include going to the gym, walking, gardening, playing with kids, swimming, playing sport, or whatever gets you sweating! So get moving - combining exercise with cognitively stimulating activities throughout the lifespan is the best way to maintain brain health well into old age.
The INSPIRED study at UNSW Australia is interested in the lives of people with younger onset dementia and their carers. We are currently recruiting people aged 45 to 70 who do not have dementia to act as a comparison group in a study of risk factor exposure. If you are interested in participating, please contact Monica at firstname.lastname@example.org.
1. Nyberg, J., Åberg, M. A. I., Schiöler, L., Nilsson, M., Wallin, A., Torén, K., & Kuhn, H. G. (2014). Cardiovascular and cognitive fitness at age 18 and risk of early-onset dementia. Brain, 137(5), 1514–1523.
Monica Cations and CHeBA Co-Director Professor Henry Brodaty after running the 2014 City 2 Surf for Team CHeBA