September 12, 2008
Men and women who are married or partnered at midlife are at lower risk of developing Alzheimer's disease and other forms of dementia in old age. Those are the findings of a study of Finnish seniors presented at the Alzheimer Association's International Conference on Alzheimer's Disease in Chicago.
The research adds to a growing body of evidence showing that staying socially connected with spouses, family and friends helps to preserve memory and keep the brain young. Earlier this year, for example, researchers at Harvard found that men and women in their 50s and 60s who remained close with family and friends as they aged appeared to have sharper memories. [See the story, "An Active Social Life Helps Keep the Mind Sharp"] Social interaction may be good for those who care for a loved one with Alzheimer's, too. Dr. Mary Mittelman and colleagues at New York University have shown that maintaining a close network of family and friends who can be called on for emotional support may be critical for easing the stress of caregiving. [See the story, "Social Support Is Key for Alzheimer's Caregivers"]
The current study showed that people who were always single, or divorced and single, during middle age were two to three times as likely to develop dementia as their married or partnered peers. Though their risk of Alzheimer's was increased, they were not as at risk as those who had suffered trauma due to the death of a spouse. Indeed, those whose partner had died and who remained widowed and single at midlife fared the worst, with nearly six times the risk of Alzheimer's as their married peers.
"This suggests two influencing factors -- social and intellectual stimulation and trauma," said study author Krister Håkansson, a researcher in psychology at Växjö University and the Karolinska Institute in Sweden. "In practice, it shows how important it is to put resources into helping people who have undergone a crisis. If our interpretation holds, such an intervention strategy could also be profitable for society considering the costs for dementia care."
For the study, the researchers examined data from more than 2,000 people in Finland who were first surveyed around age 50. The same men and women were then surveyed again 21 years later, when they had reached their 70s. They found that people living with a spouse or partner during the middle years were 50 percent less likely to develop dementia than people living alone.
How long a person had been single and for what reasons also affected the chances of developing dementia. Those who had lived alone their entire adult life ran twice the risk, while those who were divorced in midlife and remained subsequently single ran three times the risk. Widows and widowers who remained single were six times more likely to develop dementia.
Marriage and partnership is thought to provide social as well as intellectual stimulation that may help to keep the brain working well into old age. The researchers did not look at such factors as the quality of the marriage or the effects of children on outcome. But, they plan to continue their research into this provocative area.
"Does it matter, for instance, if the relationship is a happy one or not?," asked Mr. Kakansson. "And does it matter if someone has always intended to live a single life or not?"
2008 Alzheimer's Association International Conference on Alzheimer's Disease, July, 2008, Chicago.