Spirometry for asthma

When you need it and why

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If you have symptoms that could be asthma, your doctor should perform a simple breathing test to confirm whether you have that disease or another health problem. Otherwise, you could be treated with asthma drugs when you don’t have the disease, or go untreated for asthma when you do. But many people who need the test don’t receive it. Here’s why that’s a bad idea.

The test helps diagnose and manage asthma.

Some doctors rely only on symptoms such as wheezing, shortness of breath, and coughing to decide whether a patient has asthma. But those symptoms can also stem from the common cold, bronchitis, pneumonia, heart disease, or other common conditions. On the other hand, you and your doctor might dismiss those symptoms, assuming they reflect a mild problem when in fact they indicate asthma. That’s why you should have spirometry—a test that measures air flow in and out of your lungs—if you have symptoms that could be asthma. The test can help confirm if asthma is the cause and if it is, help determine your treatment, and see how well that treatment is working. If your asthma is well controlled, your doctor may cut back your medication so you don’t use more than you need. If it is poorly controlled, you might need to step up your medication to prevent an asthma attack.

Skipping the test can pose risks.

If your doctor assumes you have asthma when you don’t, you could be prescribed unneeded asthma drugs while the real problem is over-looked. On the other hand, untreated or poorly controlled asthma can lead to severe asthma attacks. About nine people die from such an attack every day in the U.S. Untreated or poorly managed asthma may even lead to a condition in which the lungs become scarred and asthma medicines don’t work as well.

The test can prevent needless expense.

A spirometry test generally costs less than $100. Not having the test can cost a lot more money. If the test shows that you do not have asthma, this can save you $200 to $300 a month for asthma medicines. If you do not have the test and you have asthma, an emergency room visit for an asthma attack can cost $3,500 or more.

When should you have it?

People five or older who have symptoms that could be asthma should undergo spirometry along with a physical exam and detailed medical history. To confirm the diagnosis, your doctor should give you asthma medicine and then retest you to see if your results improve. In many cases, spirometry should be repeated four to six weeks after you start treatment, when symptoms worsen, and at least every one to two years.

Using This Information

This information is provided for you to use in discussions with your health-care provider. The content is for educational use only and is not a substitute for professional medical advice, diagnosis, or treatment. Unfortunately, we cannot help you with individual medical questions. Always seek the advice of your physician or other qualified health-care provider with any questions you may have regarding a medical condition. Never disregard, avoid, or delay in obtaining medical advice from your doctor or other qualified health-care provider because of something you read in this report. Use of this report is at your own risk. Consumer Reports, the American Academy of Asthma, Allergy, & Immunology (AAAAI), the ABIM Foundation, and their distributors are not liable for any loss, injury, or other damage related to your use of this report.

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Published by Consumer Reports © 2012 Consumers Union of U.S., Inc., 101 Truman Ave., Yonkers, NY 10703-1057. Developed in cooperation with AAAAI for Choosing Wisely, a project of the ABIM Foundation. Portions of this report are derived from AAAAI's “Five Things Physicians and Patients Should Question” list. © 2012 AAAAI. All Rights Reserved.