Cardiac patients suffering from depression are at
greater risk for new cardiac events or cardiac death
than patients without depression. It is still
unclear which underlying mechanisms play a role in
this adverse relationship. Researchers from Tilburg
University, the Veterans Affair Hospital in San
Francisco, and VU University Medical Center in the
Netherlands suggest that inflammatory processes
could be involved (Psychoneuroendocrinology, August
2012).
The researchers followed 667 patients with stable
coronary heart disease for 6 years to investigate
the relationship between depressive symptoms and
white blood cells – a marker for inflammation.
Patients were asked about their feelings of
depression annually and their blood was drawn at the
first and last assessment to determine their white
blood cell count. These levels are a reflection of
ongoing inflammatory processes in the body but are
also involved in the formation of atherosclerosis,
an important precursor of cardiac disease.
Because health behaviors such as smoking, physical
activity and overweight have a great influence on
both depression and cardiac disease, patients were
also asked to rate these behaviors.
The results showed that patients who repeatedly
experienced depressive symptoms (depressed at two or
more interviews) had a higher white blood cell count
after 5 years of follow-up compared to those
reporting depressive symptoms at one interview or
not at all. Further analyses showed that this
association was independent of the presence of
adverse health behaviors.
The higher white blood cell count in the presence of
frequently depressive episodes could possibly
explain why cardiac patients with depressive
feelings are at greater risk for new cardiac events
or cardiac death than those who don’t experience
depressive feelings.
For more information
Tilburg University
(MDN)
|