Understanding Asthma, Causes, Triggers and Stages.

Discover asthma triggers and how addressing them might improve your health.

Imagine taking a leisurely walk through a park bathed in sunlight, with a gentle breeze,  rustling leaves, and the satisfying fragrance of blossoming flowers filling the air. As you enjoy the beauty around you, you suddenly struggle to catch your breath.  Each breath feels like a struggle, and panic sets in. This unsettling circumstance is merely a glance into the lives of asthma sufferers.

Asthma affects around 300 million people worldwide and claims the lives of over 455,000 people annually. To put this in perspective, nearly one-third of the population has it, affecting 1 in 12 children.
But what causes asthma, how lethal is it, and how to prevent it? All will be discussed in our article here.

What Is Asthma?

Asthma is a chronic condition of lung airways in which the inflammation and constriction of the airways make it difficult to breathe. It can become life-threatening if it is not managed. Asthma may strike at any age, from infancy to senior. however, it is more frequently seen in children.

How Does Asthma Affect the Body?

Comparison of a healthy lung and Asthmatic lung

Usually, when we take a breath, air goes through our nose or mouth, down into our throat, our passageways, and then to our lungs. Our lungs are full of tiny airways that carry oxygen from the air into our blood. This is where the problem begins.

Asthma affects the human respiratory system, particularly smaller airways such as the bronchi and bronchioles. The bronchioles and bronchi are surrounded by an inner lining called Mucosa, which comprises smooth muscles. In people with asthma, the airways are chronically inflamed, which can make them hyperresponsive to specific triggers. Some triggers include tobacco smoke, pollen, dust, fragrances, exercise, cold weather, stress, and even the common cold.

When people are exposed to these triggers, an asthma attack or exacerbation can occur. It is because the smooth rings present in the smooth lining of the mucosa can become narrow, and simultaneously, the trigger worsens the inflammation, making the mucosal lining more swollen and secrete more mucus.

Under normal conditions, the body uses this mucus to clear up the air from dust particles or pollen, but in the attack period, these get blocked or obstructed, making it even harder to breathe. It is leading to symptoms.

How Common Is Asthma?

Although estimates vary by geography, age range, and other factors, asthma is believed to affect over 300 million people worldwide. It affects almost 21 million Americans aged 18 and above, making up around 8.3% of the population. Mostly children boys are more asthmatics than girls. As adults, however, females are at a higher risk than males for developing asthma, with 9.7% of adult women being asthmatic compared to 6.2% of adult men.
Based upon the racial differences are more prevalent among Blacks (10.8%), Native Americans (10.8%), and those with mixed racial or ethnic backgrounds (11.5%). It is less common in Asians (3.5%) and Hispanics (6.7%). The worldwide ratio of Whites falls around 7.6%.


Although the causes are still unclear, and no single cause has been identified, few studies suggest that asthma can be due to hereditary and environmental factors. Changes in modern society, food, or even particular diseases might be to blame. Some of these are listed below.

Genetics: Asthma is a genetically predisposed condition, often inherited, with an increased risk linked to specific genes, but the presence of these genes does not guarantee future asthma symptoms. Genetic research has researched a few, including DPP10, GRPA, and SPINK5.

Allergens: Asthmatic condition is often linked to allergic responses, with asthma being more prevalent in those already allergic to allergens such as pollen, dust mites, pet dander, mold spores, and certain foods.

Environmental Factors: Environmental factors and irritants can play a role in either triggering asthma or making existing symptoms worse. they are also known as the triggers. These may consist of:

Asthma is not caused by stress or other emotional reasons, as was once widely thought. Stress and worry may wear you out emotionally and physically, worsening asthma symptoms or even triggering an asthma attack. However, these responses are typically seen as a result rather than a cause.


Individuals with asthma may have many symptoms, including those listed below. However, the severity of symptoms varies from person to person.

  • Wheezing:  Wheezing is a whistling, hissing, or melodic sound made during breathing.
    Although wheezing is typically associated with breathing out, it can also occur during inhalation. Sometimes, this only occurs when exercising or having an illness. Not all asthmatics wheeze.
  • Coughing:  Coughing is frequently worse at night or early in the morning, making sleeping difficult. Sometimes it can be the only symptom.
  • Shortness Of Breath: A person may experience this if you feel like the lungs are suffocating. It might happen sometimes or frequently.
  • Chest Tightness: It can be felt in chilly weather or after exercise, mainly due to airway construction. A person feels like something is squishing them or sitting on their chest.

Other symptoms may include difficulty breathing and speaking, anxiety or panic, fast breathing patterns, chest pain and tightness, frequent infections, and trouble sleeping. Some people also find that engaging in particular actions aggravates their symptoms.

These symptoms might be mild or severe, come and go, stick around for a while for days, and range in intensity from person to person. Some people have very moderate symptoms, while others may suddenly have quite severe bouts. In a severe asthma attack, prompt medical attention is essential.

The key to being symptom-free, active, and healthy is recognizing these indications and discussing them with your doctor.

But sometimes, there can be a condition in which the signs and symptoms suddenly appear and worsen. It may be diagnosed as an asthmatic attack, exacerbation, or flare-up.

During an acute exacerbation, the airways swell. The muscles tighten and the airways in the lungs constrict. Normal breathing becomes increasingly difficult. Anyone with asthma is at the risk of exacerbating, with women being more reported for it. Immediate medical attention is required as it can be a life-threatening condition.

Common Types

Asthma may be classified according to etiology, presentation, and severity.

  • Allergic: Pollen, dust mites, and animal dander are some allergens that can set off allergic type. When exposed to these triggers, the immune system reacts, causing inflammation and airway constriction. Allergens include pet dander, mold, food, pollen, and dust.
  • Non-allergic:  The type that flares up in response to environmental or psychological stressors or illnesses, such as cold air, exercise, or stress. It is frequently associated with airway hyperactivity. Irritants include burning wood smell, cigarette smoke, air pollution, cleaning products, air fresheners, and perfumes.
  • Occupational exposure to irritants or allergens in the workplace, such as chemicals, dust, or fumes, can set off this form. Usually, people working in farming, manufacturing, textile, and woodwork are more prone to this.
  • Exercise-Induced Bronchoconstriction (EIB): Exercise or other physical activity triggers this kind and is characterized by coughing, wheezing, and shortness of breath during or after exercise. EIB affects up to 90% of those with asthma. However, not everyone with EIB also has asthma.
  • Aspirin-Induced: Many people have reported having asthmatic attacks after taking aspirin or NSAIDs, thus giving it its name, aspirin-induced type. It is usually a severe type affecting 9% of the asthmatic population. Adults between 20 and 50 are most susceptible to its rapid onset.
  • Cough-variant: This kind of asthma is distinguished from others by a persistent cough rather than by wheezing and shortness of breath.
  • Adult-onset: The kind that sets off later in life, such as in your 20s.
  • Severe: This type of asthma is marked by symptoms that don’t go away even when high-dose medicines are taken, and it may need extra treatments like biological therapy.

60% of all cases are attributable to allergic asthma, making it the most prevalent type.

Diagnosing Asthma 

making diagnosis team task doctors looking patient s x ray

Asthma is a lifelong condition, but it can manifest at any age. The first step in preventing asthma attacks and regaining control is receiving a diagnosis. If you have been tested and diagnosed correctly, you don’t grow out of it, but symptoms can disappear for long periods.

Asthma can be silent but persistent, even without symptoms. As your immune system matures, symptoms may change. It’s crucial to prepare for potential recurrence of the symptoms.

1- Health Examination And Screening

Upon your visit to the doctor, a healthcare provider will ask numerous questions about your health, such as

  • What are your symptoms, how long and how frequently have you experienced them, and when are they most likely to appear?
  • Do your symptoms only occur during specific seasons or environmental conditions?
  • Have you any allergies?
  • What is the nature of your job?
  • Do you catch colds or infections frequently, and do they seem to last for a long time?
  • What prescription or over-the-counter medication do you use to treat your symptoms?
  • Do you have pet birds, or do you raise pigeons?
  • What medicinal herbs or nutritional supplements do you consume? Some traditional remedies or herbs/supplements may cause side effects or interact negatively with prescribed medications.
  • Do you smoke or have smokers surround you?

Asthma tends to run in families, so your healthcare practitioner must know your medical and family histories, especially if someone in your immediate family has been diagnosed with asthma or has comparable symptoms.

Depending on the patient’s age and the availability of testing facilities, a doctor may also prescribe a chest x-ray and a spirometry test, which are frequent lung function tests.

2- Spirometry

Spirometry, the gold standard to test for asthma, is simple to do in a doctor’s office and is one of several breathing tests that determine how well your lungs are functioning. It is a simple, risk-free test that measures the amount and speed of breathing in and out and is suitable for people of all ages.

To determine how well your lungs are functioning, inhale deeply and exhale forcefully into a tube connected to a spirometer. This measures the volume of exhaled air Forced vital capacity (FVC) and the exhalation rate Forced Expiration Volume (FEV1). If specific measurements are below the normal range for a person your age, it may indicate that asthma has narrowed your airways. Your FEV1 to your FVC ratio is another important metric for your doctor to consider.

American Thoracic Society suggests interpreting the result, such as if the FVC is lower than normal, which means something is restricting the airways. For FEV1, the following chart describes the ranges,

Percentage of predicted FEV1 value Result
80% or greater Normal
70%–79% Mildly abnormal
60%–69% Moderately abnormal
50%–59% Moderate to severely abnormal
35%–49% Severely abnormal
less than 35% Very severely abnormal

As for the FVC/FEV1 ratio,  healthy lungs are indicated by a normal or increased FEV1/FVC ratio, with a higher ratio indicating better lung health, while a low ratio may indicate obstruction-related breathing difficulties. What constitutes a low ratio is as follows:

Age Low FEV1/FVC ratio
5 to 18 years old less than 85%
adults less than 70%

For re-assurances, a doctor may also give you a relieving medicine, and the spirometry is repeated if the medication has improved the result, indicating an asthmatic condition.

3- Peak Flow Meterimages 2

A Peak Flow Meter is a device that measures the quickest rate at which a person can expel oxygen from their lungs. It is utilized by inhaling deeply and blowing forcefully and as quickly as possible into the device’s mouthpiece.

During an asthmatic attack or other respiratory flare-up, the lungs’ large airways gradually constrict, delaying the rate at which air is expelled from the airways, and can be measured with a PFM. This measurement is essential for determining how well or inadequately the disease is managed.

On the side of your peak flow meter, you’ll see your peak flow score, also called your peak expiratory flow (PEF) score. Exhaled air volume is measured in liters per minute (l/min). Depending on the age, height, and gender, the result may or may not be normal. For additional information on what a “normal” score would be for you, consult your family doctor.

4- Fractional nitric oxide (FeNO) Test

Lung inflammation can be assessed using a FeNO test or exhaled nitric oxide testing. Asthma is characterized by airway inflammation and the release of nitric oxide. Inflammation of the airways may be assessed using this test by detecting nitric oxide levels. Nitric oxide gas in your breath is measured by breathing into a tube attached to a machine.

Clinicians commonly look for FeNO levels above 50 ppb as a possible indicator of airway inflammation and the need for additional investigation. FeNO levels can change according to a person’s age, sex, smoking habits, and other factors.

5- Allergy Testing

Asthmatic individuals have airways sensitive to triggers, which are unique to each individual. These triggers can be tested by an allergist, who may also measure allergen-specific antibodies in the blood through blood draws and help diagnose.

Skin testing is the preferred method for testing allergies, using a concentrated allergen pushed under the skin. This can be done by scratching or injecting a small amount under the skin with a needle. These tests can take less than 30 minutes and help determine a treatment plan based on the patient’s reaction to the allergens.

6-Provocation Testing

If you’ve been showing asthmatic symptoms, but all other tests return normal, your doctor may prescribe a test that causes a minor response in a testing facility. If you don’t have asthma, modest dosages won’t affect you.

Other tests include oximetry and X-ray.

These tests for lung function are among the most widely administered. Depending on your age, symptoms, medical history, and other factors, your doctor may perform a different lung function test to diagnose and manage your asthma.

Stages of Asthma

Like many other illnesses, asthma is categorized into different stages.

asthma stages

There are 4 different stages of asthma:

  • Intermittent
  • Mild persistent
  • Moderate persistent
  • Severe persistent

The stages of asthma, also known as steps, are determined by symptom frequency and clinical measurements of lung function. Asthmatic people, particularly children, can move up and down these stages over time, highlighting the importance of understanding each stage.

Let’s take a closer look at each stage.

First Stage: Intermittent Asthma

It is the least gentle type, also known as the intermittent one.  Symptoms of this occur fewer than two times a week and usually do not interfere with daily life.

It can also be summarized as

  • Symptom frequency: Less than 2 times a week.
  • Nighttime awakenings: Less than or equal to two times a month.
  • Severity: No impact on everyday life.
  • Treatment: Manage symptoms by using an inhaler no more than twice per week; no other medications are required.

Second Stage: Mild Persistent Asthma

In this initial phase, asthma symptoms are manageable but becoming more frequent and disruptive to your daily life. And increases in the severity of symptoms might hinder normal routines. There may be a modest reduction in lung ventilation, but it is typically not severe.

  • Symptom frequency: More than twice weekly but not regularly.
  • Nighttime awakenings: 3-4 times a month.
  • Severity: Minor impact on everyday life and living.
  • Treatment: Symptoms can be prevented and managed with inhaled steroid therapy.

Third Stage: Moderate Persistent Asthma

The second most severe stage with waking one up in the middle of the night at least once a week, if not more often.  Lung function tests frequently demonstrate a significant reduction in airflow.

  • Symptom frequency: Almost daily.
  • Nighttime awakenings:  More than once a week but not every night.
  • Severity: Some impact on everyday life and living.
  • Treatment:  Regular usage of a quick-relieving inhaler is required. Steroids and long-acting bronchodilators can also treat it.

Fourth Stage: Severe Persistent Asthma

Severe persistent asthma is the most severe form of the condition. Patients with advanced conditions will have continuous symptoms throughout the day. They’ll also frequently awaken in the night hours. A person in this stage may feel as though they are having a constant flare-up. It’s hard to get through the daily things one needs to do, and the quality of life is severely affected. Lung function tests reveal a significant decrease in ventilation.

  • Symptom frequency: Daily throughout the day.
  • Nighttime awakenings:  Almost every night.
  • Severity: Significant impact on everyday life and living.
  • Treatment:  Regular usage of a quick-relieving inhaler is required. Usually requires an oral steroid.

Also, it is best to know that asthma’s severity will likely evolve over time. Either the intensity will decrease or increase. If you and your healthcare providers work together carefully, you might find the best answer for you.

The only person who can analyze your symptoms and provide you with an answer based on your particular circumstances is a trained medical professional. For this reason, you should go to the best primary care doctors to diagnose asthma and assess its severity.

What are the best preventive or treatment strategies for asthma? We have covered this in a spin-off for this article which you can check here.

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Dr Aimen

Being a Doctor by profession, Aimen is passionate about helping people get better health in their lives. Aimen enjoys her research on Prime With Time subjects and strives to create better awareness of the problems and changes related to women's health.

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