When it comes to controlling your asthma symptoms, one size does not fit all. Everyone with asthma suffers from inflammation and airway constriction, but symptoms are different for each person — and can change over time. Work with your doctor to master the three steps to better asthma control:
- Track your symptoms. Keep an asthma symptom diary. At each visit, talk to your doctor about how severe your symptoms are and if they've changed since your last appointment.
- Check your lung function. Use lung function tests to assess how well you can breathe.
- Adjust your treatment. Based on your symptoms and lung function tests, you and your doctor can make changes to your treatment if needed.
Check your lung function
Lung function (pulmonary) tests can help you and your doctor judge how well you are controlling your asthma and may ward off flare-ups. One test you can use at home to keep track of how well you can breath. Another test you'll have during doctor visits.
Peak flow meter. By learning how to use a peak flow meter, you can help detect subtle changes in your airways before you notice symptoms. Your doctor can give you instructions on how to deal with low readings and prevent a flare up.A peak flow meter can be used at home to measure how well you can force air out of your lungs. It helps detect subtle narrowing of the airways before you notice symptoms. If the readings are lower than usual, it's a sign your asthma may be about to flare up. Your doctor can adjust your treatment based on the readings. Peak expiratory flow (PEF) tells you the fastest rate at which you force air out of your lungs.
Spirometer. A spirometer is used by a medical professional to measure narrowing of your bronchial tubes. This device measures the volume of air you can exhale after you've taken a deep breath. A spirometer also shows how quickly you can get air out of your lungs. This measurement is called forced expiratory volume-1 (FEV-1). Your doctor compares the result with the predicted result for people of the same age, sex, race and height who don't have asthma. This comparison is expressed as a percentage. Lower percentages indicate less lung power.
Here's how lung function measurements correspond to different grades of asthma severity:
| Level of severity | Forced expiratory volume-1 (FEV-1) or peak expiratory flow (PEF) |
|---|---|
| Mild intermittent | At least 80% |
| Mild persistent | At least 80% |
| Moderate persistent | 60% - 80% |
| Severe persistent | 60% or less |
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