Losing a spouse may be linked to multiple health issues, but dementia isn't one of them, according to a new study.
For certain seniors, widowhood may even delay dementia, the researchers found.
"For those who had a mild memory problem, losing the spouse was associated with a later age of developing full-blown dementia compared to those who stayed married," said study researcher Dr. Bryan Woodruff.
Woodruff, an assistant professor of neurology at the Mayo Clinic in Scottsdale, Arizona, can only speculate on the reasons for this perceived association.
Widowed men and women may get more outside support and attention, he said. "It may be that social support, that network trumps the widowhood effects we see in other conditions," he said. "We don't know that for sure."
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The difference in brain functioning was significant: Among seniors starting to slip mentally, those who were widowed during the study period progressed to full-blown dementia about a decade later than those who were still married.
Woodruff is scheduled to present two studies on widowhood and dementia at an international meeting of the Alzheimer's Association in Copenhagen, Denmark.
His other research project found no increased dementia risk in adults who were mentally sharp at the study's start and later lost their spouse.
In both studies, Woodruff took into account a genetic predisposition for dementia and other factors that might affect risk or progression, and the findings held.
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Still, studies presented at medical meetings are typically viewed as preliminary until published in a peer-reviewed journal. "It's premature to say this is definitive," said Woodruff. Other studies need to be done to confirm the results, he said.
The message for loved ones of widowed older adults, whether their relative has memory problems or not? Provide more support, Woodruff said, and get help sooner rather than later if memory problems occur.
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More than 5 million Americans have Alzheimer's disease, the most common form of dementia, according to the Alzheimer's Association. The progressive brain disorder is marked by memory problems, confusion and difficulties managing day-to-day life. Slight memory and thinking problems – called mild cognitive impairment – can progress to Alzheimer's.
Widowhood has been linked with health problems, including depression and "broken heart syndrome", Woodruff said. But little is known about its effect on dementia, and he wanted to learn more.
Nearly a 10-year difference
In the first study, his team started with about 3,800 married men and women starting to show some brain decline. They excluded people who got divorced or separated during the study or left no follow-up information. Of the roughly 2,500 people remaining, 134 lost a spouse during the study period, which ran from 2005 to 2013.
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Almost 1,100 developed dementia. But those who were widowed progressed to dementia at age 92 roughly, while those who didn't lose a spouse were demented by age 83 – nearly a 10-year difference, the researchers found.
In the other study, Woodruff and his team evaluated more than 6,000 men and women who were married and had no memory issues when they entered the study. After excluding those who divorced or provided no follow-up information, they followed more than 4,400 men and women for an average of nearly four years.
Of that group, 218 developed dementia. However, those who were widowed weren't likely to develop it any sooner than the married group. For both, the median age was 96. (Half developed it sooner, half later).
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Dean Hartley, director of science initiatives for the Alzheimer's Association, was surprised by the findings involving participants with mild impairment.
"We had thought that increased stress [with spousal loss] would accelerate a person with [mild cognitive impairment] going on to dementia," said Hartley, who was not involved with either study.
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