Educated people are better able to cope with the physical effects of dementia, and even one extra year of education can significantly cut the risk of developing the brain-wasting disease, scientists said on Monday.
The findings by scientists from Britain and Finland could have important implications for public health at a time when populations in many countries are rapidly aging and dementia numbers are expected to rise sharply.
The researchers found that people who go on to university or college after leaving school appear to be less affected by the brain changes, or pathology, associated with dementia than those who stop education earlier.
"More education is not associated with any differences in the damage to the brain, but people with higher education can cope with that damage better," Hanna Keage from Cambridge University, who worked on the study with an Anglo-Finnish team, said in a telephone interview.
Over the past decade, studies on dementia have shown that the more time you spend in education, the lower your risk of dementia — but until now scientists had not known whether this was because education somehow protected the brain against damage, or because it made people better able to cope.
In this study, published in the journal Brain, post-mortem examinations showed that the pathology, or changes, in the brain, were similar in those who were educated for longer and those who were not, but the disease's affects on more educated people was mitigated by their greater ability to cope.
Keage said this may be due to psychological strength, which might allow those with more education to think around problems presented by their disease or find ways to overcome them.
It also found that for every extra year of education there was an 11 percent decrease in the risk of developing dementia.
Around 35 million people around the world have dementia. Its most common form is Alzheimer's disease, in which patients gradually lose their memory, their ability to understand the world and to look after themselves. Despite decades of research, doctors still have few effective weapons against it.
Developing ways of preventing dementia is becoming more and more important for governments worldwide as the number of dementia cases globally is expected to almost double every 20 years to 66 million in 2030 and over 115 million in 2050, and the cost of coping with the disease in aging populations is forecast to rise dramatically in the coming decades.
Keage's team said that in the United States for example, if the onset of dementia could be delayed by two years in those aged over 50, there would be nearly two million fewer cases of dementia over the next 40 years — a reduction that would also dramatically cut the projected economic costs of the disease.
The scientists examined the brains of 872 people who were involved in three large European studies of aging and who, before their deaths, had completed questionnaires about their education, when they left school and if they went to university.
"Our study shows education in early life appears to enable some people to cope with a lot of changes in their brain before showing dementia symptoms," Keage said.