You find yourself in tears for no good reason. Your outlook is gloomy for weeks at a time. Your family, friends and coworkers are all tiresome and taxing, and you could really do without them. Your daily routine is something you dread, and you'd rather just stay in bed. Nobody seems to understand how you feel, so you keep it to yourself. Occasionally it seems like it'd just be whole lot simpler if you weren't even alive.
Speculative links between heart disease and depression were first established in the late 1980s. Since then, further research has concluded that depression may be a contributing factor toward heart troubles. There are a few obvious reasons why people who are depressed are more likely to suffer from heart disease:
- Depressed people are more likely to smoke, drink excessive amounts of alcohol and avoid exercise.
- They're less likely to take heart medication if they already suffer from heart disease.
- Mental stress that comes with depression may increase plaque formation in the arteries.
- Depression could increase the production of free radicals and fatty acids, damaging the lining of the blood vessels.
The people most likely to suffer from depression linked to heart disease are the elderly. And sadly, they're the least likely to seek treatment for depression. Nineteen to 30 percent of people age 65 and older experience signs of depression [source: Elderweb]. Women are generally more depressed than men, and those living alone are more prone to be depressed. A study performed by Dr. Curt D. Furberg of Wake Forest University found that in 4,500 elderly participants with no history of heart disease, those who showed signs of depression had a 40 percent higher risk of developing coronary disease.
Another study in Baltimore, Md., found that depressed people of all ages are four times more likely to have a heart attack in the next 14 years following the study. When you consider that one in three Americans will die from some form of heart disease and that medical doctors often miss the diagnosis of depression, it's clear there's a real problem. Research is still in the early stages, but some researchers feel that depression may be as much of a factor in heart disease as high cholesterol and blood pressure.
The link between heart attacks and depression is clear -- what's fuzzy is which came first, the chicken or the egg? People that are depressed are more likely to have a heart attack, and heart attack victims are more likely to be depressed.
Fibrosis and Fight-or-flight: Physiology Meets Psychology
The human heart depends on one thing to function, and apologies to the romantics of the world -- it's not love. The heart needs to pump efficiently, plain and simple. Healthy hearts contract and expand like a rubber band. When the tissue of the heart stiffens up, it doesn't flex and pump blood like it should. This is called fibrosis. The University of Maryland School of Medicine performed a study on 880 adults and found that people who are depressed are more likely to suffer from fibrosis.
Something of a chain reaction is taking place here. A blood protein called C-reactive has been linked to inflammation of the heart and blood vessels. Inflammation increases the production of collagen, the fibrous protein that connects your skin, bones, tendons and muscles. The problem with collagen is that if you have too much of it, it stiffens the heart. The study showed that depressed adults have higher levels of C-reactive than folks who are happy-go-lucky.
Another study has pinpointed a second protein that may help to explain the link between depression and heart attacks. This one is called tumor necrosis factor alpha (TNF-alpha), and it's a member of a happy little protein family called cytokines. The cytokines can be your friend or your enemy. They're manufactured by your white blood cells and stimulate the immune system to help to fight injury and infection. However, in doing so it also causes inflammation, which we've learned is bad for the heart. People that suffer heart failure typically have high levels of TNF-alpha. The study by Ohio State University found that depressed individuals have higher levels of this protein. Getting back to the chicken and the egg, researchers aren't sure if the depression is causing the inflammation that leads to the heart failure or if the heart failure causes the depression that leads to the inflammation. Got all that?
Here's where matters get worse. Depression, stress and anxiety go hand in hand. So much so that scientists have classified a Type-D personality -- short for distressed. We've all been depressed at one time or another and we can all probably agree that it takes a toll on the body. You can't eat and you can't sleep. Your blood pressure increases, your heartbeat may speed up and you could even see a rise in insulin and cholesterol levels -- all from stress and anxiety. When your stress levels are up, your heart is going to be working overtime because of your jacked-up stress hormones, like adrenaline and cortisol. This kind of reaction is normal if faced with danger -- it's called the fight-or-flight response and it's necessary to help us handle stress. But with fight-or-flight, there's a fall in stress levels once the threat is gone. With depression and anxiety, it's like constantly having your terror alert set to red -- not good for your heart.
Post Heart Attack Depression
A recent and frightening survey by the British Heart Association showed that four out of 10 people get their information about heart attacks from movies and television. But what could be a useful educational tool is doing more harm than good -- the Hollywood heart attack is a far cry from the real thing. Onscreen, you may see your favorite heartthrob dramatically clutching his chest and collapsing in a heap just before he can reveal the secret location of the diamond stash.
Heart attacks are different for everyone and symptoms vary. Central chest pain can happen, but it can also quickly shoot through your arms, neck and jaw. You may feel a dull, bothersome ache -- some people may not even realize they're having one. You could feel sweaty, short of breath, clammy or light-headed. It might feel like someone is squeezing or stabbing your chest. You might even think it's just indigestion.
Fifty percent of heart attack victims go on to experience symptoms of depression after their traumatic events -- 20 percent experience major depression [source: Pozuelu]. You may think you'd simply feel lucky to be alive, but it's a little more complicated than that. Maybe you're down on yourself for the years of self-abuse that led to your body breaking down. Maybe it's simply a grim reminder of your own mortality. What's important to know is that this is completely normal -- unless it persists for more than a few weeks. If you can't manage to snap out of it after that, then you may be headed for more trouble. The Harvard Mental Health Letter says that depressed patients admitted to the hospital for heart attacks are two to four times more likely than average to die within the next year.
Here's some scary statistics for you loners out there. Men who go home to an empty house after being released following a heart attack have twice the mortality rate of those who live with someone [source: Pozuelu]. And if you live an isolated lifestyle, rarely checking in with friends and family, you're more likely to die after recovering from a heart attack, regardless of what kind of shape you're in.
So far, cardiologists have been slow to jump on the depression bandwagon. One reason is the old chicken and the egg. Despite the research done so far, no one knows for sure which one comes first. Factors typically associated with depression definitely lead to heart disease, and being depressed after a heart attack seems to lead to further troubles. But only long-term research would get to the bottom of the whole thing. There's plenty of speculation and theories, but no hard biological evidence that depression causes heart disease and that treating depression reduces heart-related mortality.
Cardiologists are more inclined to use a physiological explanation than a behavioral one. And who can blame them? They're heart doctors, not psychiatrists. This is where you come in. Since we know now that depression could lead to heart trouble, take matters into your own hands. If you have signs of depression, see someone about it. Talk therapy is effective at battling depression, and new anti-depressant drugs are much safer for your heart than the cardio-toxic drugs of the 1980s. Exercise provides a double whammy -- fighting both heart disease and depression. If you're out of shape, bite off small chunks. Set reasonable goals like taking daily walks and build from there. Most importantly, don't isolate yourself from others -- reach out to friends and family for help. There's much more at stake than your state of mind.
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More Great Links
- "Depression Can Break Your Heart." National Institute of Mental Health. 2008. http://www.locateadoc.com/articles.cfm/1038/37
- "How Depression Hurts Your Heart." health.com. 2008. http://www.health.com/health/condition-article/0,,20189121,00.html
- "Symptoms Of Depression May Worsen Heart Failure." Science Daily. Sept. 8, 2005. http://www.sciencedaily.com/releases/2005/09/050908082829.htm
- Atkins, Lucy. "What does a heart attack feel like?" guardian.com. August 5, 2008. http://www.guardian.co.uk/society/2008/aug/05/health.advertising
- Cromie, William J. "Depression is bad for the heart: And heart disease can be depressing." Harvard University. 2008.http://www.news.harvard.edu/gazette/2006/03.09/11-depression.html
- Eldelson, Ed. "Depression After a Heart Attack Dangerous for Years." medicinenet.com. March 7, 2008.http://www.medicinenet.com/script/main/art.asp?articlekey=87701
- Elias, Marilyn. "Study: Depression can exacerbate heart failure." USA Today. March 11, 2008. http://www.usatoday.com/news/health/2008-03-11-depression-heart- failure_N.htm
- Levin, Aaron. "Depression, Heart Disease: Links Remain Elusive." psychiatryonline. August 5, 2005.http://pn.psychiatryonline.org/cgi/content/full/40/15/33
- Pozuelu, Leo M.D. "Depression and Heart Disease." Clevelandclinic.org. 2008. http://my.clevelandclinic.org/heart/prevention/stress/depressionandheart.aspx
- Stevenson, Karen. "Depression Linked to Heart Disease in Older People." elderweb.com. Oct. 11, 2000. http://www.elderweb.com/