Can depression cause heart attacks?

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.

Mental Disorder Pictures

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.

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.