Spirometry results: understanding asthma diagnosis and management

Asthma is a chronic respiratory condition in which airway inflammation leads to breathing difficulties. Spirometry is one of the most commonly used tools in the diagnosis and management of asthma, thanks to its capability to assess lung function and identify airflow limitations.

In this article, we will explore how understanding spirometry results can be crucial for early diagnosis and effective management.

What is asthma: symptoms and causes

Asthma is a long-term inflammatory disease affecting the airways – bronchi and bronchioles – that causes swelling and the production of extra mucus. The swelling and mucus cause the airways to narrow, making it hard for the air to pass through. Because of that, asthma is classified as an obstructive respiratory disease.

Asthma can be caused by different factors. Genetics may play an important role, but exposure to environmental factors, like airborne allergens, chemicals, or smoke, can also lead to the onset of symptoms.

Common symptoms include coughing, shortness of breath, wheezing, chest tightness, reduced tolerance to physical activity, and sleep difficulties. Symptoms can worsen in case of a respiratory infection like a cold or a flu.

There is currently no cure for the disease, but treatments can help patients manage the symptoms and live a normal life.

Spirometry parameters indicative of asthma

Spirometry can measure several lung function parameters, with the most relevant for asthma diagnosis being:

• FVC, or Forced Vital Capacity. This is the total amount of air a patient can exhale after a deep breath. FVC measurements may be normal in asthma, or be slightly reduced in severe cases.
• FEV1, or Forced Expiratory Volume in 1 Second. This is the amount of air exhaled in the first second of the FVC maneuver. In patients with asthma, FEV1 is often reduced due to airway obstruction.
• FEV1/FVC Ratio. This is a key indicator of airway obstruction. If the FEV1/FVC ratio falls below a certain threshold, this is another indicator of obstructive patterns.

Another way spirometry can help diagnose asthma is by performing a bronchodilator reversibility test, which means spirometry is repeated after the patient has been administered a bronchodilator. A visible improvement of lung function, with increased FEV1 and normal FEV1/FVC ratio, further supports an asthma diagnosis.

What to do if an asthma diagnosis is confirmed

The role of spirometry in the management of asthma doesn’t end at the diagnosis. Spirometry can also help assess asthma severity and monitor treatment response, enabling the patient to enforce strategies for a better quality of life.

With the help of their physicians and healthcare providers, asthma sufferers can develop and follow the best course of action for their cases. Common strategies involve lifestyle changes, medications, and regular monitoring, as mentioned below.

Lifestyle modifications

The first step to prevent asthma crises is knowing one’s triggers and actively avoiding them. Less exposure to airborne allergens like mold, pet dander, or dust can reduce airway irritation and lower the chances of an attack. Keeping the house clean, choosing hypoallergenic clothes and textiles, and avoiding going out during allergen peak hours are all useful habits for a better respiratory health.

Maintaining a healthy weight and dedicating time every day to mild to moderate physical exercise is also useful to improve a patient’s overall health.

Treatment plans

Once asthma is diagnosed, a healthcare professional will evaluate which medication to prescribe and follow the patient’s progression to decide whether or not adjustments are needed.

Common asthma medications include:

• Short-acting beta-agonists, or SABAs, usually prescribed for mild or intermittent asthma
• Low-dose inhaled corticosteroids, as a controller therapy for moderate asthma.
• A combination of long-acting beta-agonists, or LABAs, and ICS, in more severe cases

Regular spirometry assessments

Thanks to the opportunities offered by telemedicine in the digital era, regular spirometry assessments can be performed at home with the use of a smart spirometer.

Being consistent with tests and measurements helps patients get more in control of their own health, enforces relationships between patients and healthcare providers, and allows physicians to monitor progression and evaluate the need for intervention in case of lung function decline.

Choosing the best for your spirometry tests

With over 30 years of experience, MIR is a world-renowned company in the field of oximetry and respiratory care. With several solutions for the diagnosis and management of respiratory diseases in professional diagnostic, home-based care, and clinical trials, MIR’s products are available in more than 100 countries.