Researchers Link Anxiety, Sudden Cardiac Deaths
Men who complain of high anxiety are up to six times more likely than calmer men to suffer sudden cardiac death, researchers say.
Anxiety is proving to be one of the strongest risk factors for sudden cardiac death, even more so than smoking, said Dr. Ichiro Kawachi, assistant professor of health and social behavior at the Harvard School of Public Health.
Sudden cardiac death is an electrical phenomenon that throws off the rhythm of the heart. It is different from a heart attack, which occurs when a clot inside the artery causes a blockage of blood flow.
Although scientists do not fully understand how it happens, intense psychological stress may trigger episodes of irregular heart rhythms that lead to sudden death, said Kawachi, the lead researcher on two studies done by separate teams of Boston scientists.
One was a 32-year study of 2,280 men, published in the November issue of Circulation, a journal of the Dallas-based American Heart Assn. The project was established by the Veterans Administration.
Participants were asked five questions about their anxiety level, including: “Do strange people or places make you afraid?” and “Do you often become suddenly scared for no good reason?”
Their answers helped researchers construct an anxiety scale ranging from zero to five. During 32 years of follow-up, 131 cases of fatal coronary heart disease, including 26 sudden cardiac deaths, occurred among the participants.
The risk of sudden cardiac death was 4 1/2 times higher in the study’s anxious participants than it was in men who reported no symptoms of anxiety.
In the journal’s May issue, Kawachi and another team of researchers reported the results of a two-year study of about 40,000 male health professionals. They were asked eight questions about their anxiety, such as, “Do you find yourself worrying about getting some incurable illness?” and “Do you worry when relatives are late coming home?”
The risk of sudden cardiac death was six times higher among the most anxious than it was among those who had no symptoms of “phobic” anxiety.
By comparison, the risk of sudden cardiac death among smokers was only twice as high as it was among nonsmokers, Kawachi said.
Dr. Gary Weingarden, a Dallas-area cardiologist not involved in either study, said Friday that stress could be a contributing factor in heart failure. But he did not believe a person would drop dead simply because of high anxiety.
He said possible underlying causes could be coronary artery disease, or a weakened or abnormal heart muscle.
Because only men were included in both studies, Kawachi and his colleagues now are looking at anxiety levels among more than 200,000 women in another Harvard-based study.
