Will a low-dose aspirin a day keep the doctor away?
Aspirin, the old standby for headaches, fevers and aching joints, is now widely used in the fight against cardiovascular disease and looks like a good bet to stave off colon, prostate and pancreatic cancer and perhaps cancers of the esophagus, stomach and rectum, as well.
While the old medical advice, ``Take two aspirin and call me in the morning'' is often offered in jest, aspirin helps provide relief for most of the things that ail you, which helps account for the fact that 29 billion aspirin tablets are taken each year in this country.
Today, two out of five of those who take aspirin do so to lower their risk of cardiovascular disease, according to Bayer, the company that first introduced the old wonder drug in 1899.
Medical research during the past 10 years indicates that aspirin, an anti-inflammatory and blood-thinning drug, can help protect against anything that in any way involves the production of prostaglandins, chemicals responsible for fever, swelling and pain.
Scientists aren't sure exactly how aspirin may help to prevent cancer, but they theorize it is the result of limiting the production of prostaglandins.
A 1996 study, published in the New England Journal of Medicine, involving 10,000 people who regularly took aspirin for arthritis in Finland found that the drug cut their risk of developing colon cancer by almost 50 percent.
Follow-up studies published in the NEJM last March found that patients who had been treated for colorectal cancers had a lower rate of recurrence when they took a daily dose of aspirin and that aspirin reduces the growth of polyps in the colon that may lead to cancer.
Still, concern over the risks of aspirin therapy - ranging from nausea and heartburn to stomach ulcers and bleeding - keep a lot of people from taking full advantage of the benefits. And some people are allergic to aspirin.
Although the advantages of aspirin for patients with known cardiovascular disease, especially those who have a history of heart attacks, strokes and severe angina, far outweigh the risks, healthy people with a low risk for cardiovascular disease should carefully consider those risks, says Dr. Sidney Smith, a cardiologist and former president and chief scientific officer for the American Heart Association.
`Aspirin is routinely recommended for secondary prevention - that is, to prevent recurrence of heart attacks, strokes and severe angina in patients who have already suffered such cardiovascularevents' - as well as to prevent such events from occurring in people at risk \Rprimary prevention\S unless they are allergic to aspirin or have problems with bleeding,'' Smith says.
AHA guidelines recommend aspirin for all patients with known atherosclerotic (artery-clogging) vascular disease, unless it is counter-indicated because of the risk of bleeding problems, Smith said.
He is lead author of the Heart Association's latest ``Guidelines for Preventing Heart Attack and Death in Patients With Atherosclerotic Cardiovascular Disease.''
Aggressive risk-factor management clearly improves patient survival, reduces recurrent events and the need for interventional procedures and improves the quality of life for these patients,'' Smith said in a telephone interview Wednesday.For secondary prevention, there is no question that aspirin is valuable.''
Men over 40 and women past menopause should ask their doctors about assessing their risk of heart disease, even if they have no history of cardiovascular disease, he added.
For primary prevention,'' Smith explains,if your risk of having a heart attack is greater than 1 percent per year, you should take aspirin, unless you are allergic to it or have a history of bleeding problems,'' says Smith, a professor of medicine at the University of North Carolina Medical School at Chapel Hill.
Everyone should know his own risk, based on age, family history, blood pressure, smoking history, cholesterol and some other factors calculated in an equation to assess personal risk,'' says Smith.It should be calculated every five years.
``If you have not had a cardiovascular event but you are at high risk, we still recommend taking an aspirin, if you are not allergic and have no problems with bleeding.''
Smith, says he takes a low-dose aspirin every day because he is in an age group (he's over 45) for which aspirin is thought to have primary-prevention benefits. Most men over 45 and women over 55 are at increased risk and so should be taking low-dose aspirin.
In lower-risk people, particularly premenopausal women whose risk is less than 10 percent, the risk of hemorrhagic stroke is almost equivalent to any benefit. The daily aspirin is not recommended by the AHA for this group, says Smith.
Studies increasingly suggest it doesn't take a full adult-strength, 325 milligram aspirin to protect against heart attacks and strokes. Most doctors recommend 81 to 160 milligrams, a low-dose aspirin coated to help protect against gastric irritation and bleeding.
The aging population continues to increase the number of patients living with cardiovascular disease, and recent studies show that too few Americans who have heart disease take aspirin to prevent a recurrent heart attack and other cardiovascular problems.
Three years ago, ``Circulation: Journal of the American Heart Association/ reported that only 26 percent of people who had heart disease and could have benefited from aspirin therapy took aspirin as recommended by the AHA.
This was much lower than what might be expected,'' said the study's lead author, Dr. Randall Stafford, assistant professor of medicine at Harvard Medical School.It shouldn't necessarily be 100 percent, because not everyone can take aspirin without developing complications. But it should be more than 26 percent.''
The study's review of 10,952 doctor visits by people with heart disease revealed a relatively dramatic increase in patients taking aspirin, from 5 percent in 1980 to 26 percent in 1996.
Still, Stafford says even if aspirin use were double what he found in the study,``that would still suggest a problem of inadequate use.''
Today as many as 90 percent of those who have had a heart attack are prescribed aspirin, but the number taking it for primary prevention is still low, Smith says.
As for taking aspirin during a heart attack or stroke, the Heart Association says the most important thing to do if any warning signs occur is to call 911 immediately.
``In particular, don't take an aspirin, then wait for it to relieve your pain. Don't postpone calling 911,'' the AHA guidelines say. After you call 911, if you know you aren't allergic to aspirin, it's probably a good idea to take one.
Research shows that getting an aspirin early in the treatment of a heart attack, along with other emergency treatment, can significantly improve chances of survival.
Taking aspirin during a stroke isn't advised because not all strokes are caused by blood clots. Some are caused by ruptured blood vessels, and taking aspirin can make bleeding strokes worse.
For general prevention of heart disease, the federally sponsored Preventive Services Task Force recommends a daily low-dose aspirin for:
Men older than 40
Women past menopause
Younger people with risk factors for cardiovascular disease, such as smoking, high blood pressure, diabetes or high cholesterol.
Risks may outweigh the benefits if you have:
A history of peptic ulcer, liver or kidney disease
High blood pressure
A bleeding disorder
ONLINE: American Heart Association, www.americanheart.org
Aspirin Foundation of America, www.aspirin.org.
c.2004 Fort Worth Star-Telegram