SATURDAY, March 29 (HealthDay News) -- Emphasizing an old adage, new medical research confirms that keeping stress levels under control can significantly reduce the risk of a heart attack or death in patients with coronary artery disease.

Although a correlation between stress and various heart ailments has been established in the past, this is the first observational study to examine the effect of anxiety or depression treatment on a heart patient's risk factors, according to lead study investigator Yinong Young-Xu of the Lown Cardiovascular Research Foundation in Brookline, Mass.

The research, which was to scheduled to be presented Tuesday at the American College of Cardiology's annual meeting in Chicago, examined 516 patients with coronary artery disease. Those who reduced or kept their anxiety level steady were as much as 60 percent less likely to have a heart attack or die compared to those who had an increase in anxiety level, the study concluded.

This ratio remained steady after adjusting for other potential cardiovascular risk factors including age, sex, education, marital status, smoking, hypertension, diabetes mellitus, previous heart attack, body mass index, total cholesterol, blood pressure, heart rate, ejection fraction and exercise treadmill test duration, the report said.

Patients were divided into three groups according to their baseline level of anxiety -- high, intermediate and low. Heart conditions in the study included irregular heartbeat (arrhythmia), atherosclerosis ("hardening of the arteries"), and atherothrombosis (blood accumulation leading to clotting).

Researchers asked patients about their feelings and moods, sleep patterns, irregularity in bowel or stomach functions and other stress markers. In addition to anxiety, the questionnaire also measured depression, hostility and physical complaints.

"These findings should reinforce to cardiologists a need to attend to the whole patient by paying attention to psychological problems in addition to cardiovascular disease," Young-Xu said in a prepared statement.

He added that the lifetime prevalence of anxiety disorder is around 30 percent among people with heart disease.

"If we can lower heart patients anxiety level, we may be able to reduce their risk of heart attack and prolong their life," he added.

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