Asthma diagnosis can be difficult. The signs and symptoms can vary greatly in severity and frequency and may be similar to those of other respiratory disorders, cardiovascular disease and even psychological.
If asthma is suspected, your asthma specialist will ask you about your health and family history and perform a physical exam breathing tests. He or she may perform this exam before and after medication to determine your body’s response to treatment. Your asthma specialist may perform other tests to determine your asthma triggers.
When assessing your medical history, your asthma specialist may ask you about your attacks, how often they occur and what seems to trigger them. It is helpful to keep a diary or log of your symptoms and when they occur to help identify your asthma triggers. You may see patterns of asthma symptoms that occur only during certain times of the year or in certain places or times of the day.
Your doctor may ask you about related health conditions that can coexist and complicate asthma management. These conditions include history such as a runny nose, sinus infections, reflux disease, rheumatologic disease, immune dysfunction, psychological stress, and sleep apnea.
Your physician may ask about your family history of asthma and allergies. He or she also may ask whether you have asthma symptoms and when and how often they occur.
Your doctor will listen to your breathing and look for signs of asthma or allergies. These signs include wheezing, a runny nose or swollen nasal passages, and allergic skin conditions (such as eczema).
Keep in mind that you can still have asthma even if you don’t have these signs on the day that your doctor examines you.
The doctor also may order other diagnostic tests including:
Lung Function Tests
Your doctor will use a test called spirometry which measures the narrowing of your bronchial tubes by checking how much air you can exhale after a deep breath and how fast you can breathe out.
Your doctor also may give you medicine and then test you again to see whether the results have improved.
If the starting results are lower than normal and improve with the medicine, and if your medical history shows a pattern of asthma symptoms, your diagnosis will likely be asthma.
This is a test to measure how sensitive your airways are. Using spirometry, this test repeatedly measures your lung function during physical activity or after you receive increasing doses of cold air or a special chemical to breathe in.
This test may help exclude asthma and lead to further investigation to other conditions with similar symptoms as asthma, such as other lung disease, cardiac disease, gastrointestinal reflux disease, vocal cord dysfunction, sleep apnea, etc.
A chest x ray , Echocardiogram, EKG (electrocardiogram), sleep study, GI evaluation, rhinolaryngoscopy, or other test may be ordered . These tests will help find out another disease may be causing your symptoms.
Peak Flow Meter Test
A peak flow meter is a simple device that measures how hard you can breathe out. Lower than usual peak flow readings are a sign your lungs may not be working as well and that your asthma may be getting worse. Your doctor may give you instructions on how to track and adjust management for symptoms and low peak flow meter readings.
If you have asthma, inhaling a known asthma trigger called methacholine will cause mild constriction of your airways. If you react to this trigger, you have airway hyperreactivity that suggest asthma. This test may be used if your initial lung function test is normal.
Visit the section on Allergy Testing to find out which allergens affect you, if any. Allergies can trigger intermittent or chronic asthma symptoms. It is important to clarify asthma triggers for avoidance and treatment.
Diagnosing Asthma in Young Children
Most children who have asthma develop their first symptoms before 5 years of age. However, asthma in young children (aged 0 to 5 years) can be hard to diagnose.
Sometimes it’s hard to tell whether a child has asthma or another childhood condition. This is because the symptoms of asthma also occur with other conditions.
Also, many young children who wheeze when they get colds or respiratory infections don’t go on to have asthma after they’re 6 years old.
A child may wheeze because he or she has small airways that become even narrower during colds or respiratory infections. The airways grow as the child grows older, so wheezing no longer occurs when the child gets colds.
A young child who has frequent wheezing with colds or respiratory infections is more likely to have asthma if:
One or both parents have asthma
The child has signs of allergies, including the allergic skin condition eczema
The child has allergic reactions to pollens or other airborne allergens
The child wheezes even when he or she doesn’t have a cold or other infection
The most certain way to diagnose asthma is with a lung function test, a medical history, and a physical exam. However, it’s hard to do lung function tests in children younger than 5 years. Thus, doctors must rely on children’s medical histories, signs and symptoms, and physical exams to make a diagnosis.
Doctors also may use a 4–6 week trial of asthma medicines to see how well a child responds.
Complications of under treated asthma can include missed days of work, school, inability to exercise, interference with sleep and daily activities. Poorly treated asthma is associated with increased risk of Emergency visits and can cause death. Overall quality of life is impaired.