Why Stress Strains Health of Elderly Caregivers
(HealthDay is the new name for HealthScoutNews.)
MONDAY, June 30, 2003 (HealthDayNews) -- Researchers say they have found a molecular reason why a stressful old age can lead to bad health.
Looking after a spouse with Alzheimer's disease or another form of dementia causes a marked increase in blood levels of interleukin 6 (IL-6), a molecule that weakens the immune system and causes inflammation that can lead to heart disease and a wide range of other illnesses, says a report in this week's issue of the Proceedings of the National Academy of Sciences.
A Ohio State University study found IL-6 levels rose steadily and steeply in 117 caregivers for spouses with dementia, at a much greater rate than that seen in 106 older people not giving care.
And those high levels and lower immune system functions lingered, even up to three years after the ill spouse had died, the researchers found. Some earlier studies had indicated there could be a rebound after a period of bereavement.
IL-6 is a cytokine, a member of a large family of proteins that regulate many cell functions. IL-6 has been connected with heart disease because it stimulates production of C-reactive protein, an inflammatory molecule identified as a cardiovascular risk factor. It is also known to attack immune system cells, reducing the body's defense against disease. Previous studies have linked elevated levels of IL-6 with diabetes, osteoporosis, some forms of cancer and general frailty.
The study ran for six years and started with the participants completing a series of tests for levels of stress, depression and loneliness. Blood samples were also taken and tested at least twice a year.
IL-6 levels normally go up with age. But a persistent difference between the two groups soon emerged.
"We found that the caregivers' average rate of increase in IL-6 was about four times larger than that of the control group," says a statement by study leader Janice Kiecolt-Glaser, a professor of psychology and psychiatry at Ohio State.
The study found "no evidence that the difference in IL-6 patterns between caregivers and controls were simply a function of chronic health problems, medications or health habits," the report says. That "suggests that a chronic stressor is capable of substantially augmenting normal age-related increases, effectively prematurely aging the immune system."
"The most disturbing finding," says Dr. S. Mitchell Harmon, director of the Kronos Longevity Research Institute in Phoenix, "was that even after the caregivers were at least in theory relieved of their burden by the death of a spouse, they didn't recover as people do after a sudden death."
More must be done, but at the moment "we don't know what we can do to help these people," Harmon says. "The bottom line is that we need to do more to relieve the stress of caregiving, or we will have a group of people in the population who are prematurely aged and are most likely to get sick. That is truly a disturbing thought."
More information
You can learn about stress and how to control it by visiting the National Library of Medicine and the American Institute of Stress.
