Comment by Dr Lyndel Shand and Dr Barbara Murphy, Australian Centre for Heart Health
Each year, more than 55, 000 Australians will have a heart attack. The good news is that more people are surviving compared to 20 years ago. With increasing advances in medical science, our health care systems have become highly efficient in fixing hearts and getting people home quickly. However, while our bodies may now recover physically, the emotional impacts of a heart event can be long-lasting.
There is a well-established body of evidence linking heart disease and depression. Depression in heart patients is a serious concern. For every 5 patients who have a heart event, 1 will experience severe depression following discharge from hospital. Patients experiencing depressive symptoms following bypass surgery or myocardial infarction (MI) are more likely to be readmitted to hospital within 30-days and die prematurely.
The link between depression and risk for a repeat heart event or premature death may be in part explained by poor adherence to lifestyle changes in depressed patients, who are more likely to smoke, have a poor diet and low physical activity levels, less social support, and more likely to drop-out of cardiac rehabilitation.
However, the link between depression and heart health appears to be more complex than just increased prevalence of classical cardiovascular risk factors. Increasing evidence indicates that major depression is an independent risk factor for the development and progression of coronary heart disease. The psychobiological mechanisms underlying this link are complex but evidence indicates the sympathetic nervous system, platelet function, and inflammatory and autoimmune mechanisms play a role in the development of both cardiac disease and depression.
Suicide following a heart event is also of significant concern with emerging evidence suggesting that risk of suicide is substantially increased following MI. Results of a large Danish cohort study indicated that suicide risk is 64 times higher in the first month after discharge from hospital. Persons aged 40-59 years with a history of mood disorder (i.e. depression, anxiety or psychiatric illness) were particularly vulnerable to suicide following MI.
Despite it being well-known that depression following a heart event is common and burdensome, only 10% of patients report receiving information about the emotional aspects of their heart event.
It is vital that health professionals remain vigilant to, and talk to patients about, depression and suicide risk following a heart event. Regular screening in accordance with current best practice guidelines is key to early intervention and prevention of poor outcomes.