Depressive symptoms appear to correlate with the development of coronary artery disease, but hostility and anxiety may not, Jesse C. Stewart, Ph.D., and his associates reported in the Archives of General Psychiatry.
Several studies have linked various negative emotions with the development of coronary artery disease in initially healthy subjects. But teasing out the relative contributions of depression, anxiety, and hostility has been difficult because they tend to overlap. Dr. Stewart and his associates of the University of Pittsburgh assessed a wide range of such symptoms in a prospective cohort study of subclinical atherosclerosis in healthy subjects aged 50–70 years.
The 324 subjects underwent ultrasonographic assessment of carotid intima-media thickness (IMT), a noninvasive measure of subclinical atherosclerosis, as well as a battery of tests evaluating emotional factors, including the Beck Depression Inventory, the Beck Anxiety Inventory, the Cooke-Medley Hostility Scale, and the State-Trait Anger Expression Inventory.
During 3-year follow-up, only mild to moderate depressive symptoms correlated with the decreasing carotid IMT that signals progression of subclinical atherosclerosis. Symptoms of anxiety, hostility, the experience of anger, and the expression of anger showed no correlation with carotid IMT change.
This suggests that depression, but not anxiety or hostility, is involved in the initiation and/or the progression of atherosclerosis. This study is the first ever to report an association between depressive symptoms and carotid IMT change, the investigators said (Arch. Gen. Psychiatry 2007;64:225–33).
The exact mechanism underlying this association is unclear, but depression is known to affect physiologic pathways also involved in atherosclerosis, such as autonomic nervous system dysfunction, hypothalamic-pituitary-adrenal axis dysregulation, inflammatory processes, and altered platelet function, they said.
A post-hoc analysis of the data showed that IMT worsening was associated with somatic-vegetative symptoms of depression such as fatigue, sleep disturbance, loss of appetite, and anhedonia, but not associated with more cognitive-affective depressive symptoms such as sadness, pessimism, discontent, or indecisiveness.
It is possible that this is attributable to a genuine physiologic link between the somatic-vegetative symptoms of depression and the process of atherosclerosis. However, it also is possible that older people such as the subjects in this study simply are more likely to report somatic-vegetative symptoms rather than emotional symptoms, the investigators noted.