Better screening urged to understand link between heart disease & depression

It has long been thought that depression increases the risk of dying in the year following a heart attack.

However, a Black Dog Institute study indicates the risk is associated with depression coming on after the heart attack.

The title of the study is: Timing is Everything: The Onset of Depression and Acute Coronary Syndrome Outcome and involved almost 500 patients suffering heart conditions.

The study appears in the American journal, Biological Psychiatry.

Professor Gordon Parker, executive director of the Black Dog Institute, said the way in which depression and heart disease are linked was still poorly understood.

“Since the 1980s, there have been numerous large studies suggesting that when people have suffered a major cardiac event such as a myocardial infarction, those with depression have a much poorer prognosis than those without depression,” said Professor Parker.

“Our study challenges the view that any experience of depression necessarily increases the risk of a poorer outcome in those with acute coronary syndrome (ACS).”

The Institute found that depression developing after hospitalisation for an acute coronary syndrome substantially increased the chance of subsequent cardiac death or rehospitalisation, but depression that pre-dated the ACS admission did not.

Professor Parker said the study made it clear that screening for people who develop depression following their cardiac event would help identify those who are at high risk.

So it appears that the ‘timing’ of the depression may be important, but what are the implications of this, if confirmed?

“We know that there are a number of biological changes that occur in depressed patients that may be related to their poorer cardiac outcome, such as increased blood clotting, sympathetic nervous system activity and inflammation,” he said.”

“Depressed people are also more likely to smoke, are less likely to exercise, and less likely to take their heart medication.

“We don’t, however, know which factors are most responsible for the association between low mood and poorer cardiac survival.

“Identifying depression timing as playing a key role may help to ‘narrow the field’ and shed light on the underlying mechanisms behind the association.”