When a patient has heart failure, their damaged heart isn't able to pump blood, and the oxygen it carries, effectively to the rest of the body. Symptoms of the condition, also known as congestive heart failure, range from swelling in the hands and feet to fatigue to damage to internal organs.
Close to half of patients diagnosed with heart failure will report being depressed, and of those people, about a third will experience serious depression. Now, it appears that having depression can make heart failure worse. Psychologist James Blumenthal, from Duke University in Durham, North Carolina, led a study in which researchers surveyed several hundred cardiac patients about their mood.
"We were assessing for symptoms of depression, says Dr. Blumenthal. "[It] involves feeling sad, being irritable, feeling worthless, feeling guilty, feeling easily fatigued, having disturbances of sleep and feeling that life wasn't worthwhile."
Blumenthal found that patients who reported many of these symptoms did worse than patients who didn't:
"We found that [patients with] elevated levels of depression were also more likely to die or be hospitalized, and that the increased risk of being in the hospital or dying was associated with depression over and above the severity of their cardiac condition" he notes.
Earlier studies have found similar results. What is unique about Blumenthal's work is that his researchers also took physiologic measurements of the patients' cardiac function. They found patients with more severe depression had increased levels of a protein created by damaged hearts. He says there are other physical changes that seem to take place in patients who are depressed.
"There's some data to suggest that patients with depression may have greater clotting of the blood," he says. "They may have lower heart rate variability, which is an indicator of autonomic nervous system dysfunction. They also may show dis-regulation of their blood vessels, blood vessels may not respond normally to various stimuli."
Blumenthal says this research underscores the need for doctors to assess their cardiac patients for depression and to aggressively treat it when they do find it. The study appears in the Archives of Internal Medicine.