People who care for partners with Alzheimer's or another form dementia are at an increased risk of developing the same devastating condition themselves, warns a new study.
The novel study from Utah State University says it’s possible that physical and mental stress of caring for a loved one with memory robbing condition can do lasting damage to the brain's memory centre of the caring spouse.
Dementia care giving, which can be exhausting and stressful, is already linked in previous studies to depression, physical and cognitive problems and death. Now it seems this neurological disorder can trigger dementia in spouses of dementia sufferers.
In their research, the Utah research team found that spouses of dementia sufferers are six times more likely to develop the condition themselves, with the link being stronger for men who cared for their wives.
They also found that men had a higher risk than women. Having a wife with Alzheimer's disease emerged as a prominent risk factor for men.
To reach their findings, the researchers’ team, headed by Dr. Maria Norton, an associate professor at Utah State University's Department of Family Consumer and Human Development, spent 12 years tracking the health of 2,442 people or 1,221 married couples, aged 65 and older who were dementia-free at the start of the study.
After 12 years of follow-up, the researchers found that of the 1,221 couples, who had been married for an average of 49 years, 225 subjects were affected with the condition.
Of 225 dementia sufferers, there were 195 cases of dementia in only the husband (125) or wife (70), and 30 cases of dementia in both spouses.
After taking into consideration factors such as genetics and social class, the researchers found that people with a spouse who developed dementia were six times more likely to develop dementia themselves than people whose spouses never had dementia.
Male caregivers at greater risk
They also found that men had a higher risk than women. Having a wife with Alzheimer's disease emerged as a prominent risk factor for men. They were at 11.9 higher risk compared to women’s 3.7.
Older age was also significantly associated with dementia risk, making the psychological burden heavier for ageing spouses.
"You still have a separate, unique, independent association in its own right. It's not their age or their gender or their genes," said study's principal investigator Dr. Norton.
Risks and challenges the caregivers face
A dementia caregiver faces physical, mental and emotional challenges while caring for a declining spouse, which may put him/her at risk, Norton suggests.
"This is a continual, gradual decline," Norton said. "Eventually it gets to the point where they may not recognize you. You have this grief process too -- grieving the loss of the relationship."
In addition, couples who live together for many years may be exposed to the same lifestyle risks.
"Two people living the same lifestyle may be exposed to the same risk factors so it could be possible that spouses both develop dementia," said Professor Clive Ballard of the UK Alzheimer's Society in a statement released in response to the study, reports NY Daily News. "However there has been limited research in this area and more is needed to determine which people are the most vulnerable."
More research requires
Meanwhile, study authors say that more research is needed to determine why the risk increases.
"Future studies are needed to determine how much of this association is due to caregiver stress compared to a shared environment," Norton said in a news release. "On the positive side, the majority of individuals with spouses who develop dementia did not themselves develop dementia, therefore more research is needed to explore which factors distinguish those who are more vulnerable."
"Given the significant public health concern of Alzheimer's disease and other dementias, and the upcoming shift in population age composition, continued research into the causes of dementia is urgent," Norton said.
Funded by the National Institute on Aging, the study was published May 5 in the Journal of the American Geriatrics Society.
Dementia is a neurological disorder marked by a progressive decline in mental capabilities especially memory and functioning, which can be caused by diseases such as Alzheimer's and Parkinson's, as well as stroke and infections to the brain.
It results in a loss of mental abilities such as thinking, remembering and reasoning. Although it is believed that genetics play a role in dementia, recent studies reveal that lifestyle factors might also influence the severity of the problems.
Alzheimer's is the third-largest killer in the U.S. after heart disease and cancer.