(Ivanhoe Newswire) -- Intense distress and fear of dying, which many people experience during a heart attack, are not only fairly common emotional responses but are also linked to biological changes that occur during that event. These changes are associated with other biological processes during the following weeks that can predict a worse outcome for patients.

Acute coronary syndrome (ACS) is a medical emergency stemming from blockage of the coronary arteries, resulting in either a heart attack or unstable angina. The symptoms usually include chest pain, shortness of breath, sweating, nausea, and vomiting. ACS patients are at risk of further heart problems and a worse quality of life in the future.

Researchers sought out to discover whether there was an association between the intense emotional responses of patients suffering ACS and levels of cell-signaling molecule- tumor necrosis factor alpha (TNF alpha)- that is involved in inducing systemic inflammation. They also wanted to see whether the emotional response and TNF alpha correlated with the indicators of worse biological function and worse prognosis three weeks later.

A total of 208 ACS patients were studied. The researchers assessed the patients' level of distress and fear of dying and measured levels of TNF alpha within two or three days of hospital admission.

"We found that, first of all, fear of dying is quite common among patients suffering a heart attack; it was experienced by one in five patients. Although survival rates have improved tremendously over the last few decades, many patients remain quite frightened during the experience," Professor Andrew Steptoe, Head of the Department of Epidemiology and Public Health and British Heart Foundation Professor of Psychology at University College London (UK), was quoted as saying.

"Secondly, fear of dying is not just an emotional response, but is linked into the biological changes that go on during acute cardiac events. Large inflammatory responses are known to be damaging to the heart, and to increase the risk of longer-term cardiac problems such as having another heart attack. We found that, when compared with a low fear of dying, intense fear was associated with a four-fold increased risk of showing large inflammatory responses, measured by raised levels of TNF alpha. Interestingly, this was independent of demographic and clinical factors such as the severity of the cardiac event," Steptoe said.

"Thirdly, fear of dying and inflammatory responses in turn predicted biological changes in the weeks following an acute cardiac event, namely reduced heart rate variability and alterations in the output of the hormone cortisol. These processes may contribute to poor outcomes in the longer term," Steptoe explained.

These findings could suggest new avenues of research to improve the management of ACS patients.

"Care for patients with acute heart disease has improved greatly over recent decades, but we are still concerned about people who recover in the short-term, but remain at risk for repeat heart attacks or other cardiovascular problems. This research is an illustration of how closely emotional, behavioural and biological responses are integrated. Patients' emotional responses are relevant to how they react biologically, and vice versa," Steptoe said.


SOURCE: European Heart Journal, published online June 1, 2011