One way that social isolation and suppressed anger can get "under the skin" and lead to illness is by reducing the variability in how the heart rate responds to daily stress, a team of Swedish scientists has found.
Decreased heart-rate variability is a sign of physiological rigidity and lowered ability to respond to stressful events. The person then becomes more vulnerable to a range of diseases, Myriam Horsten, Kristina Orth-Gomér, PhD, MD, and colleagues at the Karolinska Institute in Stockholm report in the January-February issue of Psychosomatic Medicine.
The researchers studied 300 healthy women between ages 30 and 65 who were taking part in the Stockholm Female Coronary Risk study. They were free of any symptoms of heart disease and without hospitalization for any illness during the previous five years. Those who tested high for social isolation and inability to discuss their anger showed more limited variability in their heart rates during their normal daily activities. They were monitored using ambulatory 24-hour electrocardiograms.
The research sought to track associations between psychosocial risk factors and indicators of heart rate variability in healthy women that would put them at risk for disease, extending to a healthy population a large body of previous research on the causes and effects of heart rate variability.
Decreased heart rate variability has been found in both depressed psychiatric patients and depressed cardiac patients, and has been shown to be a predictor of coronary heart disease and atherosclerosis. It has also been associated with "all cause" mortality in other studies.
The research was supported by grants from the National Institutes of Health, the Swedish Medical Research Council, the Swedish Labor Market Insurance Company, and the Swedish Heart and Lung Foundation.
Psychosomatic Medicine is the official peer-reviewed journal of the American Psychosomatic Society, published bimonthly. For information about the journal, contact Joel E. Dimsdale, MD, editor-in-chief, at 619-543-5468.
Posted by the Center for the Advancement of Health http://www.cfah.org. For information about the Center,
call Richard Hebert, 202-387-2829 rhebert@cfah.org
Journal
Psychosomatic Medicine