Dear HEALTHbeat subscriber,

In decades past, if you were suffering from a headache, the first bottle you’d reach for would probably be the aspirin. But aspirin’s profile has changed greatly in recent years and is now well known as a tool to keep hearts healthy and prevent cardiovascular problems. Even so, uncertainty remains over who should take aspirin daily and how much is needed. This issue of HEALTHbeat helps you make sense of newly updated recommendations on preventive aspirin use. Also in this issue, Dr. Celeste Robb-Nicholson discusses the pros and cons of taking peppermint oil.

Wishing you good health,


Nancy Ferrari
Managing Editor
Harvard Health Publications
HEALTHbeat@hms.harvard.edu

The plusses and minuses of preventive aspirin use

For men, the main benefit of aspirin is preventing a heart attack. For women, it’s preventing the kind of stroke caused by a blood clot (ischemic stroke). It’s the most common kind of stroke. For both, the risks of taking aspirin are gastrointestinal bleeding and hemorrhagic stroke.

It makes the most sense to take aspirin if your chance of having a heart attack or stroke is greater than the odds of aspirin causing a problem. The simplest way to figure your heart disease or stroke risk is to use an online calculator, such as the Framingham or Reynolds risk scores, which give you a percentage. If yours is 13% it means that for every 1,000 people with risk factors like yours, 130 will have a heart attack or stroke over the next 10 years.

Now compare your cardiovascular risk with the chance that taking aspirin will lead to gastrointestinal bleeding or cause a hemorrhagic stroke. The estimates of these complications look like this: before age 59, 0.9% for men and 0.5% for women; from 60 to 69, 2.5% for men and 1.3% for women; and from 70 to 79, 3.7% for men and 1.9% for women.

Several things boost the chances of getting into trouble with aspirin:

• Regular use of ibuprofen (Advil, generic) or another nonsteroidal anti-inflammatory drug in addition to aspirin increases the risk of gastrointestinal bleeding fourfold.
• Men are twice as likely as women to have gastrointestinal bleeding.
• Having had a gastrointestinal ulcer, gastrointestinal bleeding, or hemorrhagic stroke increases the chances it will recur.
• Uncontrolled high blood pressure or use of an anticoagulant such as warfarin (Coumadin, Jantoven, generic) also increases the risk for a hemorrhagic stroke or serious bleeding.

Is preventive aspirin use right for you?

Here’s how to put this information together. Say you are a 68-year-old woman with a stroke risk of 18%. By taking aspirin every day, you lower your risk by 25%, to 13.5%. (That translates into 45 fewer heart attacks or strokes for every 1,000 women taking low-dose aspirin.) Your chance of having a problem with aspirin is 1.3%. The benefits definitely outweigh the risks.

What about a 55-year-old man with a 10-year heart attack risk of 2%? Taking aspirin would lower it by 25%, to 1.5%. Since he takes ibuprofen for his arthritis, his chance of having a problem with aspirin is close to 4%. For him, the risk is higher than the benefit.

Trials evaluating the heart benefits of aspirin have tested doses ranging from 500 milligrams (mg) a day to 100 mg every other day. The task force concludes that a dose of 81 mg a day, the amount in a baby aspirin, seems to work just as well as higher doses, with fewer bleeding problems.

Beyond aspirin

Q: What are the pros and cons of taking peppermint oil?

A. Peppermint oil is extracted from parts of the peppermint plant, an herb that’s been used as a digestive aid since ancient times. Nowadays, it’s a flavoring agent in many over-the-counter health products, including toothpastes and mouthwashes. Menthol, a component of peppermint, is an ingredient in topical preparations for conditions ranging from congestion to muscle aches.

Peppermint oil relaxes the smooth muscle cells that line much of the gastrointestinal tract. It has been most extensively studied as a treatment for irritable bowel syndrome (IBS) and indigestion. Although clinical studies in people with IBS have shown mixed results, two major analyses found a modest benefit. People with IBS who took peppermint oil reported less flatulence, abdominal pain, and bloating compared with those who took a placebo. Given by enema, peppermint oil can help relieve intestinal spasms in people undergoing a barium examination of the large intestine.

Unfortunately, peppermint also relaxes the sphincter between the esophagus and stomach (the lower esophageal sphincter), so it can cause gastroesophageal reflux and heartburn. It can worsen reflux symptoms in people with hiatal hernia and — not surprisingly — those with gastroesophageal reflux disease (GERD). In studies of people with IBS, peppermint oil (generally 0.2 to 0.4 milliliters three times a day) is taken in enteric-coated capsules, which allow it to bypass the esophagus and stomach before it is broken down and metabolized.

Peppermint oil has other downsides besides its effects on the lower esophageal sphincter. At high doses, it can be toxic to the kidneys, and you should not take it if you have gallstones or active gallbladder inflammation. Finally, check with your doctor if you take any other medication, because peppermint oil can boost the blood level of some medications, including the antidepressant amitriptyline (Elavil, others) and the statin simvastatin (Zocor).

This Question and Answer first appeared in the July 2009 Harvard Women’s Health Watch, available at www.health.harvard.edu/women.