The Burrill Report


Husbands or wives who care for spouses with dementia are six times more likely to develop the memory-impairing condition than those whose spouses don't have it, according to new research that suggests the stress of caregiving may be to blame. The 12-year study, published in the Journal of the American Geriatrics Society, found that the increased risk among caregivers was on par with the power of a gene variant known to increase susceptibility to Alzheimer's disease.

Researchers have long been interested in how taking care of a spouse with dementia affects caregivers. Most previous studies have focused on the emotional distress caretakers often experience, rather than how their cognitive abilities might be affected. A few small studies have suggested that spousal caregivers frequently show memory deficits greater than spouses who aren't caregivers. However, none examined the cognitive ability of caregivers over time using standard, strict criteria to diagnose dementia.

The new study, led by researchers at Johns Hopkins, Utah State University, and Duke University, examined 1,221 married couples ages 65 or older. These individuals were part of the Cache County (Utah) Memory Study, which has identified over 900 persons with dementia in the community since 1995. All of the study participants live in Cache County, whose residents topped the longevity scale in the 1990 United States census.

In the sample of 2,442 married persons, the researchers diagnosed 255 individuals with dementia and discovered that individuals whose spouses had already been diagnosed were six times as likely to develop the condition themselves compared to those without an affected spouse.

This increased risk is comparable to the risk of developing Alzheimer's disease associated with a well-studied gene variant known as APOE ε4, the researchers report. The findings held up even when the researchers accounted for other factors that might influence the risk of developing dementia, such as socioeconomic status.

The long-term nature of the new research, the researchers say, makes the results different from earlier snapshot studies showing memory loss in spousal caregivers. “We know that the declines in memory we saw were real and persistent, not just a point in time where they weren't performing well on tests,” says Utah State University Associate Professor Maria Norton.

The researchers speculate that the stress of caregiving might be responsible for the increased dementia risk for spouses, although they say more research is need to identify what that mechanism might be. If their hunch is correct, doctors who treat dementia patients should pay more attention to efforts to decrease stress for spousal caregivers.

“Caregiving has positive aspects, as well as negative ones,” says Peter Rabin, a professor of psychiatry at Johns Hopkins University. “If we can boost the positive aspects and reduce the negative ones, we may be able to reduce a caregiver's risk of developing dementia.”


May 07, 2010
http://www.burrillreport.com/article-a_caregiver%e2%80%99s_toll.html