Most people know that smoking cigarettes greatly increases the chances of developing heart attacks, strokes, and peripheral artery disease (not to mention cancer). But they may not know that the increase in risk is immediate, from the moment you light up.
Everyone's heard statistics like this: The chances of a heart attack are as much as six times greater in women smokers, and as much as three times greater in men smokers, than in nonsmokers. The chances of dying (from heart disease or from any cause) over the next 35 years is more than 60% higher in young smokers than in nonsmokers. And cigarettes are the main cause of heart attacks in people under 40 years of age.
At the same time, quitting smoking can be very painful, so it is natural for smokers to look for ways to discount the dire statistics. So when a doctor dutifully parrots these sorts of statistics to a patient who smokes, the patient typically knits his brow as if in deep contemplation, and says something like, "Thanks for the info, doc. I'll take it into account." But what the patient is really thinking is, "Yada, yada, yada. Heard it all before."
The Truth About Smoking and Heart Attack
The statistics often don't make an impact on smokers because it's too easy for them to convince themselves that the statistics don't actually apply to them, at least not now. They'll get around to quitting, they tell themselves, when the time is right. In other words, they put it off.
Unfortunately, the way doctors often describe the problem allows smokers to find excuses to rationalize putting off the quitting process. Doctors typically emphasize the fact that smoking can accelerate atherosclerosis -- the disease process of the arteries that eventually produces heart attacks and strokes. But everyone knows that atherosclerosis is a long-term process, and often takes years, or even decades, to develop. So, smokers rationalize, there's plenty of time to quit.
Younger smokers tell themselves that smoking isn't likely to cause them a problem for many years. Older smokers tell themselves that, given they've been smoking for so long, either they have significant atherosclerosis already (in which case they're already screwed), or they don't (in which case the cigarettes must not be causing the problem in their case); and either way, what's the point of quitting now?
What people don't know -- and what doctors often fail to tell them -- is that the cigarette you smoke today can cause a heart attack or stroke TODAY, whether or not you've had any symptoms in the past.
Because, in addition to accelerating the long-term process of atherosclerosis, and causing smokers to develop heart attacks and strokes decades earlier than they might have otherwise, smoking has an immediate, acute effect on atherosclerotic plaques. That's right. The cigarette you smoke today can trigger a heart attack (or a stroke) today.
A heart attack occurs when a blood clot suddenly forms within a coronary artery, usually due to the acute rupture of a plaque. Plaque rupture can occur at any time, and often completely without warning. The resulting blood clot will often completely stop or significantly reduce the flow of blood to the heart muscle. This condition is called Acute Coronary Syndrome. If the obstruction in the flow of blood is severe enough, part of the heart muscle dies -- and this is a heart attack.
To say it another way, heart attacks usually do not happen as the result of a slow, gradual worsening of atherosclerosis. They usually occur because of the acute rupture of a plaque. And furthermore, very often the plaques that rupture are, prior to the rupture, relatively small, and are not the kind of plaques that would have concerned a cardiologist. (No stent would have been recommended, for instance.)
How Smoking Today Can Give You a Heart Attack Today
As it turns out, many of the the chemicals that tobacco products dump into the bloodstream "irritate" plaques, and likely trigger plaque rupture. Smoking is known to alter blood lipids, to increase free radicals in the bloodstream, to increase the activity of the sympathetic nervous system, to increase blood clotting, to increase vascular inflammation, and to directly damage blood vessel walls. All of these effects occur acutely -- that is, immediately after smoking a cigarette -- and persist for several days. All these things are thought to instigate plaque rupture, or to increase the chances of a rupture blocking the artery, or both.
This means two things.
First, with the very next cigarette you light, you are increasing your risk of heart attack or stroke -- right now -- and that elevated risk persists for at least 24 to 48 hours.
And second, if you quit smoking today, you are not just reducing your long-term risk of a catastrophic outcome, you are reducing your immediate, short-term risk. Within a day or two, your risk of an acute catastrophe will be substantially lower than it is now.
And this is why you should quit smoking this minute, TODAY.
Ockene, IS, Miller, NH. Cigarette smoking, cardiovascular disease, and stroke. A statement for healthcare professionals from the American Heart Association. Circulation 1997; 96:3243.
Ambrose, JA, Barua, RS. The pathophysiology of cigarette smoking and cardiovascular disease: an update. J Am Coll Cardiol 2004; 43:1731.