Peter P. Vitaliano, Ph.D., of the University of Washington, reports that while the exact path connecting chronic stress and heart disease may vary from person to person, there appears to be a general pattern — at least in men.

Vitaliano says chronic stress is associated with psychological distress; factors such as unsatisfactory social support and poor coping skills may contribute to the link, he noted.

The psychological distress is associated with poor health habits, such as insufficient exercise; poor diet; and a number of changes in body composition and metabolism that are well-established risk factors for heart disease, Vitaliano reported. Eventually, these changes in body composition and chemistry, known collectively as the metabolic syndrome, produce heart disease, he said.

Vitaliano said he and his colleagues collected the evidence for this model from a 30-month study of 152 married, older adults. Eighty of the subjects were caregivers for spouses with Alzheimer’s disease, while the other 72 adults, none of whom were caregivers, served as a comparison group, he explained.

Previous studies have shown that caregivers routinely experience numerous physical, emotional and financial stressors, according to the research team.

"The demands of caregiving, coupled with the biological vulnerabilities of aging, put spouse caregivers at increased risk [for coronary heart disease]," Vitaliano said.

Vitaliano said the research team began the study by examining each subject for attributes that tend to produce psychological distress, such as low income, high exposure to stressors and insufficient coping skills. They also assessed each subject’s level of psychological distress, including depressive symptoms and sleep problems; obtained a self-rating of exercise and diet habits; and looked for indications of metabolic syndrome, including obesity, high blood pressureand elevated levels of cholesterol, insulin and sugar, the researchers reported. All of the evaluations were repeated 15 to 18 months later, the team said.

The team said their findings revealed that the caregivers started from a more vulnerable position than the comparison group and had a greater tendency to suffer from obesity, depression and disturbed sleep. Heart disease was equally prevalent among the caregivers and comparison group when the study began; however, 27 to 30 months later, 54 percent of the caregiver men suffered from heart disease, compared to 26 percent of comparison group men, according to the findings.

"In men, the pathway from [psychological] distress to the metabolic syndrome was one of the largest pathways from caregiving to [heart disease]," Vitaliano reported.

He said the study findings suggest a direct, immediate relationship between distress and metabolic syndrome, and an indirect delayed link where distress promotes poor health habits that eventually exacerbate metabolic syndrome.

Because hormone replacement therapy (HRT) may affect many of the factors that predispose women to heart disease, the researchers divided the women into two groups: those using HRT and those who did not, Vitaliano said. Evidence of a connection between chronic stress and heart disease was less clear in either group of women than it was among the men, he added.

Funding for the research was provided by grants from the National Institute of Mental Health, the National Institute on Aging, the National Cancer Institute and the National Heart, Lung and Blood Institute.

Copyright 2002 Health Resources Publishing