Asthma diagnosis

For a proper asthma diagnosis^[5], schedule an appointment with your provider. Your provider may conduct a physical exam and ask you a series of questions about your health to determine the severity of your asthma. An asthma diagnosis can also rule out other possible conditions such as a respiratory infection or chronic obstructive pulmonary disease (COPD). You may also be given lung function tests to determine how much air moves in and out as you breathe. These tests may include:

• Spirometry^[6]. During a spirometry test, you breathe as hard as you can into a tube attached to a machine called a spirometer. This common test assesses how well your lungs work by measuring the volume and speed of your exhale. If you’ve already been diagnosed with asthma, spirometry may be used periodically to check how well your medications are working and whether your breathing problems are under control.
• Peak flow^[7]. A peak flow meter is a small, handheld device that measures how hard you can breathe out, and in turn, the degree of obstruction in your airways. Peak flow readings are higher when the airways are unobstructed. When peak flow readings are lower than usual, your lungs may not work as well and your asthma may be getting worse. Your provider will give you instructions on how to track and deal with low peak flow readings.

After your initial round of tests, your provider may give you an inhaled medication called a bronchodilator, such as albuterol, to open your airways. You’ll then do another set of measurements. Improved lung function with the use of a bronchodilator is a likely sign of asthma. Other tests^[8] to diagnose asthma include:

• Methacholine challenge. Asthmatic people typically react to inhaling Methacholine and will experience a slight constriction in their airways,
• Imaging tests. A chest X-ray and high-resolution computerized tomography (CT) scans of your lungs and sinuses can identify any abnormalities or infections that can cause breathing problems.
• Allergy testing. A skin test or a blood test may be performed. Allergy tests can identify allergies to pets, dust, mold, and pollen. If certain allergy triggers are discovered, your provider may recommend for allergen immunotherapy.
• Sputum eosinophils. This test looks in the mixture of saliva and mucus that you discharge during coughing (sputum) for certain white blood cells (eosinophils). Eosinophils may be elevated in response to infections.
• Provocative testing for exercise and cold-induced asthma. In these tests, your provider measures your airway obstruction before and after you perform vigorous physical activity or take several breaths of cold air.

How asthma is classified

Asthma presents itself in many ways and can be brought on by different triggers. The different types of disease can be separated by severity. To classify your asthma severity, your provider may ask you questions about symptoms (how often you have asthma attacks and how bad they are), along with the results of your physical exam and diagnostic tests. Asthma is classified into four general categories:

• Mild intermittent: Symptoms are mild and last up to two nights a month.
• Mild persistent: Symptoms come more than twice a week, but no more than once a day.
• Moderate persistent: Symptoms come about once a day and more than one night a week.
• Severe persistent: Symptoms come multiple times per day and often at night.

Determining your asthma severity helps your provider choose the best treatment. Asthma can be mild and require little or no medical treatment. However, some types of asthma can be life-threatening. Asthma severity often changes over time, requiring adjustments to treatment.