Asthma Overview: Types, Causes and Symptoms

What is Asthma?

Asthma is a chronic condition that affects the airways in your lungs. The CDC reported that in 2021, 7.7% of Americans, approximately 24.9 million people, had asthma, including 20.2 million adults and 4.6 million children.

The airways, also known as bronchial tubes, carry air in and out of your lungs. When you have asthma, these airways become inflamed, and narrow, and can produce extra mucus, making it difficult to breathe. This inflammation is a key aspect of asthma and is responsible for many of the symptoms associated with the condition.

Asthma is a long-term condition, meaning it doesn’t go away and requires ongoing management. The inflammation in the airways makes them more sensitive to various triggers, which can lead to episodes of breathing difficulty, commonly known as asthma attacks. These attacks can range from mild to severe, and in some cases, they can be life-threatening if not properly managed. Understanding the chronic nature of inflammation and the role of mucus production is essential for managing asthma effectively.

Types of Asthma

Asthma can present itself in various forms, each triggered by different factors and requiring specific management strategies. Understanding the different types of asthma is crucial for effective treatment and prevention. Here’s the information on the types of asthma, based on classifications from the American Lung Association:

• Allergic Asthma: Triggered by exposure to specific allergens such as pollen, mold, pet dander, and dust mites. Cleveland Clinic reports that allergic asthma is the most prevalent form of asthma.  This type of asthma is often associated with other allergic conditions, including hay fever and eczema. Symptoms typically worsen during or after exposure to these allergens, making it important to identify and avoid your specific triggers.
• Aspirin-Induced Asthma: A type of asthma triggered by taking aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs). This condition, also known as aspirin-exacerbated respiratory disease (AERD), often occurs in individuals who also have nasal polyps or chronic sinusitis. Avoiding aspirin and other NSAIDs is essential for managing this type of asthma.
• Cough-Variant Asthma: Characterized primarily by a persistent cough without the typical asthma symptoms like wheezing or shortness of breath. This type of asthma can be difficult to diagnose because the main symptom is coughing, often worsened by exercise, cold air, or allergens. Identifying and managing the underlying triggers is crucial.
• Exercise-Induced Asthma: Also known as exercise-induced bronchoconstriction, this type occurs when physical activity triggers asthma symptoms. Symptoms usually start a few minutes after beginning exercise and may worsen in cold or dry conditions. Proper warm-up routines and managing the environment where you exercise can help prevent flare-ups.
• Nighttime Asthma: Symptoms of asthma that worsen during the night, also known as nocturnal asthma. Common triggers include dust mites, cold air, or lying down, which can exacerbate symptoms. Managing nighttime asthma often involves adjusting medication routines and creating an allergen-free sleeping environment.
• Steroid-Resistant Asthma: A severe form of asthma where symptoms do not improve with standard corticosteroid treatment. This type of asthma requires a more aggressive treatment approach, often involving higher doses of medications or alternative therapies. Close monitoring by a healthcare provider is essential.
• Occupational Asthma: Caused by exposure to irritants in the workplace, such as chemicals, dust, or fumes. Common in industries like farming, hairdressing, and manufacturing, where workers are frequently exposed to these substances. Identifying and minimizing exposure to workplace triggers is key to managing occupational asthma. The American Lung Association reports that 1 in 6 cases of adult-onset asthma is due to occupational exposures.

Symptoms of Asthma

Asthma symptoms can vary from person to person, but there are several common signs to look out for:

• Wheezing: A whistling or squeaky sound when you breathe, especially when exhaling.
• Coughing: Persistent coughing, particularly at night or early in the morning.
• Shortness of Breath: Difficulty breathing, which may feel like you can’t get enough air.
• Chest Tightness: A sensation of pressure or tightness in the chest, making it harder to breathe deeply.

These symptoms can be more severe during physical activity, in cold weather, or when exposed to specific triggers such as allergens or irritants.

For those unsure about their symptoms, the Symptom Checker can be a useful tool, but remember to consult a healthcare professional for an accurate diagnosis.

Causes of Asthma

Asthma is caused by a combination of genetic and environmental factors. While the exact cause of asthma isn’t fully understood, certain factors are known to increase the likelihood of developing the condition:

• Genetic Predisposition: If you have a family history of asthma or other allergic conditions, such as eczema or hay fever, you’re more likely to develop asthma.
• Environmental Triggers: Exposure to certain environmental factors, such as air pollution, tobacco smoke, and allergens like pollen or pet dander, can trigger asthma symptoms.
• Lifestyle Factors: Obesity, stress, and lack of exercise are also linked to a higher risk of developing asthma.

Diagnosis of Asthma

Accurate diagnosis is essential for effective asthma management. The process typically involves a combination of medical history, physical examination, and specific tests to confirm the condition.

• Medical History: Your healthcare provider will start by asking about your symptoms, their frequency, and any triggers. A family history of asthma or allergies will also be considered.
• Physical Examination: A physical exam focuses on your respiratory system. The provider will listen to your lungs for wheezing and may check for signs of allergies, such as nasal congestion or skin reactions.
• Spirometry Test: Spirometry is a key diagnostic test that measures lung function, specifically how much air you can exhale and how quickly. Reduced lung function after a bronchodilator test indicates asthma.
• Peak Flow Measurement: A peak flow meter measures how fast you can blow air out of your lungs. It’s useful for monitoring asthma at home, helping to identify patterns and assess control.
• Methacholine Challenge Test: If spirometry results are inconclusive, a methacholine challenge test may be used. Inhalation of methacholine, which narrows the airways, can reveal airway hyperresponsiveness, a hallmark of asthma.
• Allergy Testing: Allergy testing helps identify specific allergens that may trigger your asthma. This can include skin prick tests or blood tests to measure your allergic response.
• Additional Tests: Other tests, like a chest X-ray or blood tests for eosinophil count, may be conducted to rule out other conditions or understand the severity of your asthma.

Treatment of Asthma

Asthma treatment involves a combination of quick relief and long-term control strategies tailored to each individual’s needs. Below is an overview of the most important treatments and methods for managing asthma effectively, based on guidelines from the National Heart, Lung, and Blood Institute.

Quick-Relief Medicines

Quick-relief medicines, or relievers, are essential during asthma attacks. If your asthma is mild or exercise-induced, these may be the only medications you need. Your doctor will likely prescribe a quick-relief inhaler, which you should carry with you at all times.

• Inhaled Short-Acting Beta2-Agonists (SABAs): These open up the airways quickly. Side effects may include tremors and a rapid heartbeat.
• Oral Corticosteroids: These reduce airway inflammation but should be used cautiously due to potential side effects.
• Short-Acting Anticholinergics: These also help open airways, though they might be less effective than SABAs.

Long-Term Control Medicines

For ongoing asthma management, long-term medications are taken daily to prevent attacks:

• Corticosteroids: These reduce inflammation and are available in pill or inhaled forms. Inhaled versions have fewer side effects but may cause a hoarse voice or thrush.
• Biologic Medicines: Used for difficult-to-control asthma, these are injected and help reduce inflammation.
• Leukotriene Modifiers: These pills reduce inflammation and keep airways open, used alone or with corticosteroids.
• Inhaled Mast Cell Stabilizers: Prevent airway swelling due to allergens.
• Inhaled Long-Acting Bronchodilators: Added to inhalers to prevent airway narrowing.
• Allergy Shots (SCIT): These help reduce allergic reactions over time.

Bronchial Thermoplasty

For severe asthma that doesn’t respond to other treatments, bronchial thermoplasty may be an option. This procedure involves using heat to thin the airway muscles, helping to prevent narrowing. However, it comes with risks, including worsened asthma and infections.

Management of Asthma

Asthma management focuses on controlling symptoms and preventing attacks. The goal is to maintain good lung function and a normal level of activity.

• Regular Monitoring: Regular check-ups with your healthcare provider are crucial for managing asthma. Monitoring your symptoms and lung function helps in adjusting treatment plans to keep asthma under control.
• Adjusting Treatment Plans: As asthma symptoms can change over time, your treatment plan may need adjustments. Working closely with your healthcare provider ensures that you are on the right track.

• Personalized Action Plan: Having a personalized asthma action plan is essential. This plan outlines what to do daily to keep asthma under control, how to recognize early signs of an attack, and what actions to take during an emergency.

Preventing Asthma Attacks

Preventing asthma attacks involves a combination of avoiding triggers, making lifestyle changes, and staying informed about your condition.

• Make Environmental Changes: Self-care is very important for controlling the attacks. Small changes at home and work can significantly reduce exposure to triggers. Use air purifiers, keep your living space clean and free of dust, and ensure proper ventilation.
• Lifestyle Adjustments: Regular exercise, maintaining a healthy weight, and quitting smoking can all contribute to better asthma control.
• Stay Vaccinated: Keeping up with vaccinations, such as the flu and pneumonia vaccines, is crucial. Respiratory infections can trigger asthma symptoms, so preventing these illnesses is key to managing asthma.