After the brain, the heart is arguably the body’s most important organ. From before we are born to the minute we die, the heart is in action, pumping oxygen-rich blood to every part of the body.
For some people, the heart doesn’t work as effectively as it should.
Heart failure affects more than 5 million people in the United States, contributing to one in every nine deaths and costing the nation $30 billion a year. Of people admitted to the hospital with heart failure, 17 to 45 percent die within one year and about half die within 5 years.
This makes it a high priority to determine what factors influence survival rates. According to new research presented at the annual meeting of the Heart Failure Association of the European Society of Cardiology in Seville, Spain, depression may play a key role.
Down and Out
The research involved patients from an ongoing study called OPERA-HF, which examines people hospitalized with heart failure.
Out of 154 patients surveyed, 103 patients were not depressed, 27 experienced mild depression, and 24 experienced moderate to severe depression. Over an average follow-up period of 302 days, 27 of the patients died.
From the results, researchers concluded patients with heart failure who experienced moderate to severe depression were at five times the risk of dying as those with mild or no depression. Even after controlling for possible other factors — including sex, age, high blood pressure, severity of the patient’s heart failure, and co-occurring medical conditions — moderate to severe depression still contributed to increased mortality.
“Depression is often related to loss of motivation, loss of interest in everyday activities, lower quality of life, loss of confidence, sleep disturbances, and change in appetite with corresponding weight change,” explained John Cleland, chief investigator of OPERA-HF and professor of cardiology at Imperial College London and the University of Hull, United Kingdom, in a press release. “This could explain the association we found between depression and mortality.”
Stanley G. Rockson, chief of consultative cardiology and professor of medicine at Stanford University, has additional ideas about the link.
The anxiety that often accompanies depression can boost the body’s adrenaline levels, which stimulate the heart and cause long-term wear and tear. Also, the long-term effects of antidepressant medications may not yet be fully understood, he said.
In the press release, Cleland urges clinicians to take these new findings into consideration.
“Clinicians should screen patients with heart failure for depression and consider referring those affected for counselling,” he said.
Rockson speculates further: “It raises the question whether people who have a chronic history of a major depressive illness should be screened for early signs of heart failure,” he said. “That would allow more aggressive interventions to try to reduce the impact of that problem.”
However, Rockson also notes that Cleland’s findings are preliminary. There’s not enough evidence yet to say there’s conclusive proof. Other unmeasured factors may be at play.
“What you’re looking at is an association between two different disease entities, which on a statistical basis establishes an alleged relationship, but it doesn’t explain how they’re related,” he said. “Very often, whenever you look at these associations that don’t have data to find the causal relationship, you have to wonder whether there are confounding variables that are really the factors at play that are present in both conditions. Therefore, the link is not depression per se, but what depression tends to keep company with.”
He added, “Observations like these don’t always hold up in the long run, so there shouldn’t be a cause of undue panic or undue concern.”
Heart Failure Is Serious Business
On the other hand, Rockson doesn’t want to minimize the importance of proper medical screening for heart failure patients.
“The take-home about heart failure is that it’s a very serious diagnosis,” he said. “It has profound implications for individuals in terms of their function and also in terms of their survival. If somebody who carries a diagnosis of depression already has of the hallmark symptoms of heart failure, of course they should bring it to the attention of their physicians promptly so that it can be evaluated and addressed.”
Signs of heart failure include:
- shortness of breath
- difficulty breathing or chest pain when exercising
- swelling in the lower parts of the body
- irregular, pounding, or fluttering heartbeat