Asthma is a chronic inflammatory disease that causes breathing problems in adults and children. It occurs due to the narrowing of the airways of the lungs. People of all ages get affected by asthma, but it is often seen in teens and children.
Types of Asthma
- Adult-onset asthma – Asthma symptoms manifest for the first time after adulthood.
- Allergic Asthma – Asthmatic attacks are triggered by allergens such as pollens, dust, and pet dander.
- Exercise-induced Asthma – Airway narrowing intensifies 5 to 20 minutes after exercise begins, and this physical exertion triggers the asthmatic attacks.
- Cough-variant Asthma – This type of asthma is triggered by respiratory infections and exercise and is characterized by severe coughing.
- Occupational Asthma – It results from workplace exposure to contaminants like fumes, smoke, chemicals, and allergens such as animal dander.
- Nighttime (nocturnal) Asthma – Asthmatic symptoms get triggered at night due to heartburn or hormone secretions that follow the circadian pattern.
- Thunderstorm Asthma – Exposure to high pollen count resulting from heavy thunderstorms during spring triggers this attack.
- Nonallergic Asthma – In this type, the symptoms flare up due to extreme weather conditions, illnesses, medications, or environmental factors.
What are the Causes of Asthma?
- The exact etiology of asthma is unknown. But asthma that starts before 12 years of age is often associated with genetic influence. If it starts after 12 years of age, then it is more likely due to environmental factors.
- A strong response of the immune system to a foreign substance in the lung is the leading cause. This substance called allergen is harmless to others but stimulates the inflammation of airways in asthmatic patients.
- Swelling and narrowing the airways with or without increased mucus production occurs and makes it harder to breathe.
- Bronchospasm due to tightening of the airway smooth muscles also increases the difficulty of breathing in some patients.
- Viral infections or exposure to allergens during childhood.
Risk factors:
- Family history and genetics – The predisposition to have asthma is often inherited. Children born to asthmatic mothers are at a higher risk of developing it.
- Gender – Boys are at a higher risk as compared to girls, although women are more likely to develop adult-onset asthma in contrast to men.
- Ethnicity – African Americans, Puerto Ricans, and Hispanics are more at a higher risk when compared to non-Hispanic white Americans.
- Allergies – Allergic reactions following exposure to pollen or other allergens during early childhood increase the risk.
- Obesity – The risk is higher in obese people due to the accumulation of excess fat in the body that decreases respiratory function.
- Atopic disease – People with a history of atopic disease (atopic eczema, allergic rhinitis, and asthma) are at a higher risk of developing asthma.
- Medications – Beta-blockers, angiotensin-converting enzyme inhibitors, aspirin, and NSAIDs often trigger asthma in susceptible people.
- Respiratory infections – Viral infections of the respiratory tract early on in life are also a risk factor.
- Occupation – The risk is more significant in susceptible people if they work in places that often expose them to industrial dust and chemical irritants.
- Tobacco smoke – exposure to cigarette smoke in the womb affects lung growth and development in the child and increases the risk.
Signs and symptoms of Asthma
- Recurrent episodes of wheezing.
- Shortness of breath.
- Chest tightness.
- Coughing, especially at night and early morning.
- Trouble sleeping.
- Symptoms aggravate due to exercise or cold air.
Complications:
The complications associated with severe cases are:
- Disrupted sleep Airway remodeling
- Respiratory failure
- Difficulty in speaking
Diagnosis: How Is Asthma Diagnosed?
- Medical history – The physician evaluates symptoms, family history, and other patient risk factors.
- Physical exam – Doctors examine the patients to identify allergic skin conditions like eczema and abnormal high-pitched breath sounds.
- Diagnostic tests –
- Pulmonary function tests –
- Spirometry – The amount of inhaled and exhaled air and the time is taken to exhale after taking a deep breath are measured thoroughly.
- Spirometry with bronchodilator tests – Patients with reduced lung functions are given bronchodilators (salbutamol) via inhalation to open/relax the airways before performing the spirometry.
- Bronchoprovocation tests – Lung function after exposure to common triggers such as allergens, exercise, methacholine, or cold air is measured.
- Fractional exhaled nitric oxide (FeNO) tests – It measures the amount of nitric oxide exhaled in the breath and quantifies airway inflammation.
- Peak expiratory flow (PEF) tests –Narrowing of the airways is detected by measuring the air flowing out of the lungs.
- Pulmonary function tests –
- Allergy skin or blood tests – The patient is exposed to common allergens to determine the one responsible for the immune reaction.
Treatment :
- Managing the symptoms and preventing asthma attacks are the main objectives of treatment.
- Fast-acting (Short-term relief) medications – These help to prevent or relieve the symptoms during an attack. It includes:
- Inhaled short-acting beta-2 agonists – Albuterol, salbutamol, etc.
- Oral and intravenous corticosteroids – Prednisone, methylprednisone, etc.
- Short-term anticholinergics – Ipratropium and tiotropium.
- Long-term control medicines – These are taken daily to prevent asthma attacks by reducing airway inflammation and preventing the narrowing of the airways. The common medications used are:
- Corticosteroids – Fluticasone, budenoside, etc.
- Biologic medicines (Monoclonal antibodies) – Omalizumab, mepolizumab, etc.
- Leukotriene modifiers – Montelukast, zafirlukast, etc.
- Mast-cell stabilizers – Cromolyn
- Long-acting bronchodilators – Salmeterol, theophylline
- Immunotherapy (Allergy shots) – A series of injections containing small doses of the allergen are given for 3 to 5 years to lose sensitivity to the allergen.
- Interventional bronchoscopic procedure –
- Bronchial thermoplasty – It reduces the airway smooth muscle and controls bronchospasms in patients with severe, uncontrolled asthma
Prevention:
- Living with it –
- Actively avoiding asthma triggers.
- Taking medications properly.
- Managing stress.
- Ensuring regular checkups to adjust treatment if needed.
- Preventing it –
- Maintaining a healthy weight.
- Quitting smoking.
- Regular physical activity.
- Getting good quality sleep.
- When to see a doctor?:
- Consult immediately with an allergist or pulmonologist if severe breathlessness or wheezing is experienced, especially at night or in the early morning. It costs around Rs. 300 to 1500 to get a pulmonary function test done.