As the average life span becomes longer, dementia becomes more common. Swedish scientist Laura Fratiglioni has shown that everyone can minimise his or her risk of being affected. Factors from blood pressure and weight to the degree of physical and mental activity can influence cognitive functioning as one gets older.
The lengthening of the average life span in the population has caused an increase in the prevalence of aging-related disorders, one of which is cognitive impairment and dementia. An expert panel estimates that worldwide more than 24 million people are affected by dementia, most suffering from Alzheimer's disease.
In more developed countries, 70% of the persons with dementia are 75 years or older. Age is the greatest risk factor for developing dementia. But there is growing evidence that the strong association with increasing age can be, at least partially, explained by a life course of cumulative exposure to different risk factors.
Risk factors for dementia
Laura Fratiglioni's research group at Karolinska Institutet, Sweden, is a leader in identifying the risk factors that lie behind developing dementia and using this knowledge to develop possible preventative strategies. The group's research has shown that the risk is partly determined by an individual genetic susceptibility, and that active involvement in mental, physical and social activities can delay the onset of dementia by preserving cognitive functions.
Further education early in life has a protective effect, and the group's research has shown that it is never too late to get started.
"The brain, just as other parts of the body, requires stimulation and exercise in order to continue to function. Elderly people with an active life – mentally, physically and socially – run a lower risk of developing dementia, and it doesn't matter what the particular activities are", says Professor Fratiglioni.
'What is good for the heart is good for the brain'
Laura Fratiglioni's research has shown that physical factors are also significant. Not only high and low blood pressure, but also diabetes and obesity in middle-age increase the risk of developing dementia after the age of 70. "What is good for the heart is good for the brain", she says.
Knowledge about risk factors and how to protect the brain from dementia is based on observational studies where scientists have discovered statistical correlations in the population. Scientists in other current studies that are carried out in Europe are investigating what happens when a large number of study participants are given special help to better control vascular risk factors and to stimulate social, physical and mental activities, which should, at least, lead to a delay of the onset of dementia.
"You could say that we are progressing from observation to experiment. This means that in a few years we will know more about which strategies are most effective in preventing neurodegenerative disorders", says Laura Fratiglioni. - (EurekAlert!, February 2011)