Reader's Corner

The studies show a two-pronged relationship between heart disease and depression: People who have heart disease and are depressed have a greatly increased risk of suffering a fatal heart attack. And, being depressed appears to make you more likely to develop heart problems and do more poorly after diagnosis. For example, a 1996 study from Johns Hopkins University followed 1,551 initially healthy residents of Baltimore for more than 13 years and found that depression increased the chance of a heart attack fourfold.

Another 1996 study, from Duke University, followed 730 men and women over a 27-year period and concluded that those with depression were 70% more likely to have a heart attack and 60% more likely to die from it than people who did not suffer from depression.

Yet, despite this evidence, researchers were not sure how depression influenced heart disease. They have not yet proven that depression actually initiates the development of plaque in the arteries. They suspect, however, that depression, which is associated with lowered levels of the brain neurotransmitter serotonin, can cause platelets (components in the blood) to become sticky, potentially forming a clot. A clot can prevent blood from passing through the coronary arteries, causing a heart attack.

Studies also suggest that psychological stress may cause fatal, abnormal heart rhythms. A susceptible heart (one that has been injured by heart attack, for instance) may be affected by the changes in heart rate and blood pressure caused by emotional stress. And there is no question that depressed people are more likely to continue smoking and to eat and drink excessively, all of which add to coronary risk.

Symptoms of clinical depression include a lack of interest in things that formerly brought pleasure, excessive guilt, inability to concentrate, lack of energy, change in appetite or sleeping habits, withdrawal from human contact, excessive crying, feelings of helplessness or hopelessness, and thoughts of suicide.

Depression is not all in your head say researchers. Emotional responses produce very real chemical changes in the body, which must be treated to recover. Don't wait: Ignoring depression could be a fatal mistake.