New research from Columbia University has found relatively healthy women living with severe depression may be at an increased risk of cardiac events, which includes sudden cardiac death (SCD) and fatal coronary heart disease (CHD).

The data, published in the March 9, 2009 issue of the Journal of the American College of Cardiology, comes from 63,468 women who participated in a Nurses Health Study who had no prior evidence of heart disease.

Self-reported symptoms of depression and use of antidepressant medication were used as a measure of depression in the study.

Dr. William Whang led the research team and found women with clinical depression were more than twice as likely to experience SCD when compared to women without the condition. Researchers also found the risk was associated more strongly with antidepressants than with depressive symptoms.

"We can’t say antidepressant medications were the cause of higher risk of sudden cardiac death. It may well be that use of antidepressants is a marker for worse depression," Whang said. "Our data raise more questions about the mechanisms by which depression is associated with arrhythmia and cardiac death."