MONDAY, Dec. 15, 2008 (HealthDay News) -- Stress increases the risk of heart attack and other cardiovascular problems by pushing people toward bad habits, new British research suggests.
"The study suggests that people with psychological stress had a 50 percent increased risk of a cardiovascular disease event over the follow-up period," said Mark Hamer, senior research fellow in epidemiology and public health at University College London, and lead author of a report in the Dec. 16/23 issue of the Journal of the American College of Cardiology. "This increased risk can largely be explained by the higher smoking rates and low exercise levels of individuals who were stressed."
Hamer and his colleagues followed 6,576 participants in the Scottish Health Study, which started with them filling out a 12-item questionnaire designed to measure their general happiness by listing such things as symptoms of depression or anxiety and recent sleep disturbances. About 15 percent of the people in the study were classified as suffering from psychosocial stress on the basis of their answers.
The researchers also collected physical data, starting with basic information on weight, height, physical activity, alcohol intake, smoking and blood levels of cholesterol and C-reactive protein, a marker of arterial inflammation.
Over a seven year follow-up period, incidence of cardiovascular events -- heart attacks, stroke, bypass surgery and the like -- was 50 percent higher among the people with a high level of depression and anxiety when compared to happier people. Smoking and lack of physical activity explained about 63 percent of the increase, with smoking alone responsible for 41 percent.
Alcohol intake explained less than 2 percent of the increase, with high blood pressure assigned 13 percent of the blame.
"Therefore, treating psychological disorders that aim to reduce cardiovascular disease risk should not only focus on the symptoms, but also on behavioral risk factors," Hamer said. "It would be beneficial for cardiologists to work with psychologists."
In such a program, "the most effective interventions might be to combine physiological approaches with intensive lifestyle changes to reduce modifiable risk factors," he said.
"This study helps us to better understand the relative contributions of stress-related changes in behavior and physiology leading to heart disease," Dr. Roland von Kanel, head of the psychocardiology unit of the Swiss Cardiovascular Center at the University Hospital of Bern, said in a statement. He wrote an accompanying editorial.
"The findings encourage us to emphasize broad preventive strategies to target the behavioral and physiological pathways leading from stress to cardiovascular disease," Kanel said.
Preventive actions "may span from behavioral interventions targeting smoking cessation and increasing physical activity to stress management and relaxation techniques," he said, adding that "whether such interventions ultimately decrease the cardiovascular risk associated with psychological stress needs further study."
The physical risk factors for heart disease are listed by the American Heart Association.