Asthma

What is Asthma?

Asthma is defined as an inflammatory disease of the airways in the lungs which causes the walls of the airways to swell, narrow, and produce mucus. The narrowed airways cause difficulty in breathing.

Is Asthma a Medical emergency?

Sometimes, a severe asthma attack can be life-threatening and requires emergency treatment.

Types

Depending on the factors that are associated with the development and exacerbation of asthma, it is classified as:

• Exercise-induced Asthma: This is developed or exacerbated by physical activity or exercise
• Occupational Asthma: This is developed or exacerbated after exposure to workplace irritants like chemicals, fumes, dust, etc.
• Allergy-induced Asthma: This is developed or exacerbated after exposure to airborne allergens like pollen, mould, dust mites, animal dander, etc.

Depending upon the intensity of the symptoms, it is classified as the following:

• Mild Intermittent Asthma: Symptoms are mild and occur once a week
• Mild Persistent Asthma: Symptoms occur more than twice a week
• Moderate Persistent Asthma: Symptoms occur daily
• Severe Persistent Asthma: Persistent symptoms

Causes

Environmental and genetic factors cause asthma. Its onset below 12 years of age results from genetic influence, and above 12 years of age may be an environmental influence. Some of the causes of its development may include:

• Respiratory infections
• Air pollution
• Exposure to environmental chemicals, fumes, and gases
• Allergens like pollen, dust, etc.
• Indoor allergens like dust mites, mould, animal dander, and cockroaches
• Certain preservatives that are added to some types of foods and beverages
• Certain medications like beta-blockers, aspirin, ibuprofen, and naproxen can cause asthma development
• Smoking during pregnancy and after delivery can cause asthma development in a child
• Psychological stress during pregnancy can cause asthma in a child

Risk factors

The factors that increase the risk of asthma may include:

• Family history
• Viral respiratory infections
• Having eczema, hay fever, or certain types of urticaria
• Obesity
• Smoking or exposure to secondhand smoking
• Exposure to workplace triggers like chemicals used in paints, farming, hairdressing, food processing, grain dust, wood dust, latex, etc.
• Exposure to exhaust fumes, traffic pollution, etc.

Triggering factors

Triggering factors are different from person to person. Some of the irritants and substances that exacerbate are:

• Physical activity or exercises
• Irritants such as chemical fumes, gases, or dust
• Airborne substances like pollen, mould, pet dander, etc.
• Cold climate
• Respiratory infections
• Aspirin intake
• Alcohol intake

Signs & symptoms

Symptoms differ from individual to individual. Some may have symptoms when exposed to specific climatic conditions, or in others, it may result from physical activity. Some may have ongoing symptoms.
The signs and symptoms may include:

• Shortness of breath
• Chest pain and chest tightness
• Wheezing (a whistling sound while exhaling air)
• Cold or flu, along with coughing and wheezing

Investigations

Along with a physical examination, pulmonary function tests are performed to be diagnosed. They include:

• Spirometry: A test to estimate the narrowing of the bronchial tubes
• Peak flow: A test to measure air flowing in and out of the lungs

Other tests include:

• Methacholine challenge
• Nitric oxide test
• Imaging tests
• Allergy testing
• Sputum eosinophils
• Provocative testing for exercise and cold-induced asthma

Diagnosis

Diagnosis is based on medical history, clinical evaluation, and investigation results.

Treatment options

Medical treatment

Medications for controlling asthma depend upon age, symptoms, and triggering factors. They include:

• Long-term Asthma control medications: These medications are taken daily to keep them under control. They are:
  • Inhaled corticosteroids: These anti-inflammatory drugs include fluticasone, budesonide, flunisolide, ciclesonide, beclomethasone, mometasone, and fluticasone furoate
  • Leukotriene modifiers: These are oral medications, and they include montelukast, zafirlukast, and zileuton
  • Long-acting beta-agonists: These inhaled medications include salmeterol and formoterol to open the airways
  • Combination inhalers: These medications include fluticasone-salmeterol, budesonide-formoterol, and formoterol-mometasone, which contain a long-acting beta-agonist along with a corticosteroid
  • Theophylline: This pill is taken daily to keep the airways open
• Quick-relief medications: These rescue medications are used for quick relief of symptoms. They include:
  • Short-acting beta-agonists: These include albuterol and levalbuterol
  • Ipratropium (Atrovent): Ipratropium quickly relaxes the airways and makes it easier to breathe
  • Oral and intravenous corticosteroids: These medications include prednisone and methylprednisolone
• Allergy medications: They are used if allergens exacerbate it. They include:
  • Allergy shots
  • Omalizumab

Interventional treatment including surgery and indications for surgery/ Surgical treatment

• Bronchial thermoplasty: This treatment is recommended for severe asthma that is not controlled with inhaled corticosteroids or other long-term medications.

Role of Diet/ Exercise/ Lifestyle changes/ Preventive measures

Some lifestyle changes and preventive measures that can be followed to reduce the symptoms and lessen the possibility of attack include:

• Keeping a clean environment
• Preventing mould and dust indoors
• Covering mouth and nose in cold climates
• Reducing pet dander
• Maintaining a healthy weight
• Regular exercising
• Keeping under control heartburn and acid reflux disorders

Complications

Other health conditions that can occur along with this disease include:

• Gastroesophageal reflux disease (GERD)
• Rhinosinusitis
• Obstructive sleep apnea
• Permanent narrowing of bronchial tubes causing trouble breathing
• Signs and symptoms that interfere with sleep and recreational activities

Prognosis

The prognosis depends upon the intensity of the condition and the measures taken by an individual to lessen the asthma attack. Complete remission is possible in a few cases.

When to contact the doctor? / How to identify the complications?

Medical consultation is required after noticing signs and symptoms like prolonged cold or flu, frequent coughing and wheezing, difficulty breathing during sleep, shortness of breath with minimal activity, etc. Detecting symptoms and treating them early may prevent long-term lung damage.

Indications for hospitalization if required

Instances that require hospitalizations are:

• Recurrent asthma attacks
• Rapid worsening of shortness of breath and wheezing
• Trouble breathing with minimal activity
• No improvement of symptoms even after the use of quick-relief inhalers

Suggested clinical specialists/ Department to consult for this condition

Pulmonary Medicine