The relationship between heart disease and depression is like that between the chicken and the egg -- hard to tell which comes first."There are areas we understand and areas where we still have questions," says Dr. Rhonda Robinson-Beale, chief medical officer for United Behavioral Health, a unit of UnitedHealth Group.The National Institute of Mental Health has found that prevalence of depression in heart attack victims can be as high as 65 percent, while as many as 20 percent of patients with heart disease experience depression -- a number that grows following heart attack or a heart bypass graft, among other heart events.The reverse can be true as well: There's a "level of relative risk" for those who have major depression to have cardiovascular disease, she says.One study found those over 55 with major depression were twice as likely to have a heart event, such as heart attack or stroke, as those without depression. Furthermore, a prior history of depression was found in 44 percent of those newly diagnosed with heart disease.The ramifications are more serious than just being depressed after a heart attack, she says. For people who become depressed there's a significantly higher incidence of mortality within six to 18 months. And greater risk of another heart attack, as well.
Robinson-Beale admits the reasons are less clear than the results. Depression has been shown to affect heart rate and its variability. There's also a known effect on blood pressure. Where most people have a drop in blood pressure at night, those with depression don't. If you add in genetic factors like atherosclerosis, she says, it's worse.Depression also makes it less likely a patient will follow doctor's orders after a heart event. He may not take medications on time or exercise or eat properly. Failure to do so puts him at risk for future complications, even death.It's also harder to diagnose depression after someone survives a heart attack. "They don't present with a negative self-image, which is very common with chronic recurring depression, or with guilt. They have a high degree of positivity, but also feelings of exhaustion and fatigue. It's hard to tell if that's cardiac disease or a worsening of depression. It makes it difficult to monitor and adequately treat when someone has a myocardial infarction (heart attack), heart failure and depression."Equally difficult is prescribing medications, because some anti-depressants, like the old tricyclates, are not safe with heart issues. And some newer drugs, while not as dangerous to the heart, can effect other cardiac medications and block their metabolism or cause drug interactions, she says.
Women stand out because there are "psycho-social risk factors as related to heart disease," Robinson-Beale says. They have higher risk of depression leading to heart events, for unknown reasons. And a higher incidence at an earlier age, between 34 and 55. A study called the Women's Ischemia Syndrome Evaluation linked depression and anger to heart-related health risks for women.
Some factors are starting to stand out in research. Single women, for instance, are managing families, may have low education and social class, and full responsibility for work and family. They may lack social support.
Researchers, she says, are just beginning to study the differences between men and women. "Keep in mind, there's not a lot of data that looks at women and outcomes."
Women are less likely to return to work after a heart event, again for unknown reasons. And drugs may act differently based on gender, although they're not sure which drugs and why.
Making the Connection
When the experts talk about depression as a risk factor for cardiac events, they're talking about major depression. When they talk about depression that occurs after a heart event, it could be major or something less severe, she says.
"We need for the patient to understand the connection between stress, emotional status and physical symptoms ... They have the ability to alter that connection, to manage it.
"The most important piece to understand is the correlation between depression and medical illness, particularly cardiac. Depression is chronic and reoccurring. Because of that, it sets an individual up to have a higher incidence of cardiac event, assuming there are other predisposing factors. Having additional psycho-social stressors, particularly common in women, adds to poor prognosis and delay in normal functioning."There is effective treatment for depression. But what's most important, she says, is not to stop treatment prematurely without the advice of a doctor. That includes both medications and therapies. "Changing one's perceptions, developing those skills, learning to manage your own emotional state and physical symptoms are very, very important." Source: Deseret News (Salt Lake City). Provided by ProQuest Information and Learning. Powered by Yellowbrix.