Lethal combination: depression and heart disease

Heart disease is a serious physical disorder. Depression is a serious neurological disorder. The two together makes a dangerous combination that is more lethal that when these disorders exist alone. This is according to a recent report in the journal Heart.

It has been shown before that there is a strong link between depressions and poor heart health. Depressed people are very likely to develop coronary heart disease. The study was based on data from the British Whitehall II study which followed up more than 10,000 civil servants. The substudy tracked almost 6000 middle aged adults for an average of 5.5 years.

The incidence of depression was significantly higher in those with established heart disease (20%) than among those without heart problems (14%). During the follow-up period, 170 study participants died, and 47 of these deaths were due to a cardiovascular event such as stroke or heart attack.

What is interesting is that depression seems to increase overall mortality risk even more than heart disease.

“Those with coronary heart disease alone were 67% more likely to die of all causes, while those who were depressed, but otherwise healthy, were twice as likely to do so as those who had neither condition.”

When heart disease and depression co-occur, the likelihood of death increases 5 times. Even after correction for other confounding factors, the mortality risk of those with the heart disease-depression combo is still 3 to 4 times higher than those who are healthy.

The link between depression and heart disease is not clearly understood. The authors postulate:

The biological explanations for the impact of depression on the risk of death are still not clear… but may involve stimulating the inflammatory process and/or clot formation, or altering cellular responses and/or the metabolism of blood fats. Behavioural factors might also play a part.

Is it a case of mind over matter? Or mind over heart? In any case, health care professionals are advised to pay more attention and watch for depressive symptoms in their cardiac patients. And psychistriatrists should do the vice versa in their depressive patients.