MONDAY, Jan. 19, 2009 (HealthDay News) -- Sociable people who don't sweat the small stuff may be more likely to remember the small stuff as they age, suggests new research exploring the link between personality and the incidence of Alzheimer's disease.
"Older people who are active, outgoing and relaxed may be less likely to develop dementia," said study author Hui-Xin Wang, with the Karolinska Institute in Stockholm, Sweden.
The study, published in the Jan. 20 issue of Neurology, adds to a growing body of evidence suggesting a link between personality traits, lifestyle and Alzheimer's disease.
According to the National Institute on Aging, Alzheimer's disease currently affects between 2.4 million and 4.5 million Americans, and that number will increase significantly as the population ages unless the disease can be effectively treated or prevented.
Researchers questioned 506 older people about their personality traits and lifestyle, to measure their sociability and disposition to stress. After six years, 144 people had developed some sort of dementia, but researchers discovered that calm, more relaxed people, whether they had active social lives or not, were 50 percent less likely to develop dementia than those who had higher levels of neuroticism.
People who were both calm and outgoing, with active social lives, were also 50 percent less likely to develop dementia.
The study found that less neurotic people were more calm and self-satisfied than their more neurotic counterparts, while outgoing people tended to be more socially active and optimistic than less extroverted people.
"Strategies to change lifestyle, such as having an active lifestyle, engagement in different leisure activities, i.e. mental, social and physical activities, or having a rich social network, may protect against dementia," Wang said.
But researchers say more studies are needed to determine whether happy people are less likely to develop dementia or whether Alzheimer's exerts an influence on well-being even before symptoms can be identified.
"The main limitation of the current study is that personality was assessed only at one occasion," said Wang. "Although personality traits are generally stable throughout the life course, individual differences in late adulthood have been observed."
"One of the things that's clear is that the pathology of Alzheimer's disease starts long before the symptoms do," said William H. Thies, chief medical and scientific officer for the Alzheimer's Association. "You might be able to find these people who we would not regard now as having Alzheimer's, but we might regard them as high-enough risk that we should entertain some sort of intervention."
But Alzheimer's researchers warn that the aging baby boomer population will continue to exert strain on an already overburdened health-care system.
"We have shrinking resources for doing any type of Alzheimer's work in a time when the population for the disease is growing, and there is clearly a mismatch between the public health imperative that Alzheimer's brings us and our reaction to it," said Thies. "What we really need are enough resources to find modifiable risk factors that we can change so that we reduce the risk of the disease and we don't see as much of it occurring."
Visit the National Institute on Aging for more about Alzheimer's disease.