Even Mild Depression Ups Heart Failure Death Risk
Mortality rate was more than 50 percent higher in seven-year study
MONDAY, March 7, 2005 (HealthDay News) -- A state of depression so mild that most doctors might not notice it significantly increases the long-term risk of death for people with heart failure, a new study finds.
Following 1,005 patients with heart failure for seven years, researchers found those whose score on a standard psychiatric test indicated mild depression were 44 percent more likely to die compared to those who scored in the normal range. Dr. Wei Jiang, an assistant professor of internal medicine and psychiatry at Duke University Medical Center, reported the findings Monday at the American College of Cardiology scientific sessions, in Orlando, Fla.
But the death rate was higher -- 51 percent -- for those whose score was slightly lower, indicating somewhat milder depression, she said.
"The majority of patients in our study would not be regarded as having clinical depression," Jiang said.
The finding is important because heart failure, the progressive loss of the heart's ability to pump blood, is increasingly common. The American Heart Association estimates that 4.7 million Americans have heart failure, with 400,000 new cases reported every year.
Jiang said she undertook the study because other trials have linked depression to an increased risk of death from other cardiac conditions, such as heart attacks. As the patients came to Duke for treatment, they were given the Beck's Depression Inventory (BDI), a test that has 21 statements such as "I am disappointed in myself" and "I hate myself," requiring a score from 0 to 3.
Persons with a BDI score of 10 are considered mildly depressed. The 44 percent increase in mortality was recorded for participants in the trial with a score of 10 or higher.
But the higher, 51 percent increase in mortality was found in people with a score of 7 or higher, Jiang said.
It's not known why depression is related to higher mortality, she said. Some research has linked it to physical effects, such as a decreased ability of the heart to respond to the stresses of everyday life. But a depressed person is also more likely to miss doctors' appointments and less likely to stick with exercise programs and drug regiments, Jiang said.
"Also, depressed patients tend to make unhealthy lifestyle choices in such areas as diet and smoking," she said.
The lesson for cardiologists is that they should pay close attention to patients' psychological outlook, Jiang said. No special training is needed to give the BDI, which can be completed in 10 minutes, she noted.
Jiang has begun a study to learn whether antidepressants can improve the outcome for patients with heart failure and mild depression. "The study has been going on for two years, and it will be three more years before we get final results," she said.
Another Duke study linking depression with a heart problem was presented Saturday at the American Psychosomatic Society annual meeting in Vancouver. A group led by Lana Watkins, an associate research professor of psychiatry, reported a strong association between depression and ventricular tachycardia, an irregular and abnormally rapid heart beat that can be a precursor of sudden death.
Testing 72 patients admitted to the hospital with heart attacks, the researchers found that 13 of them had clinical depression. The incidence of the abnormal heartbeat was three times higher in those patients than in those who were not depressed.
The finding is "a heads-up for physicians that depression is associated with this arrhythmia," Watkins said.
"There should be an increased awareness that depression increases the risk of ventricular tachycardia," she said. "The patient should be monitored by in-hospital telemetry. They should wear a monitor when they go home. If the arrhythmia appears, beta blocker medications are known to be an effective treatment."
A fact sheet that summarizes what heart patients should know about depression is offered by the National Institute of Mental Health.