Asthma: Causes, Symptom and Treatment

Introduction

Asthma is a long-term lung issue marked by swelling and narrowing of airways, making it hard to breathe. It is among the most frequent chronic illnesses globally, impacting millions across all ages, especially children.

Asthma leads to wheezing, shortness of breath, a sense of chest tightness, and coughing, with symptoms varying in how often they occur and their intensity.

Triggers for these symptoms include environmental and health-related factors like allergens, air pollution, infections, and exercise.

Causes

Asthma arises from genetic factors combined with environmental elements, leading to inflammation and airway tightening. The specific cause of asthma is not entirely known, but various contributors exist:

1. Genetic Factors: Asthma often runs in families, indicating a possible genetic aspect. Certain genes related to the immune system and inflammation seem to impact asthma’s development.
2. Environmental Factors: Environmental exposures significantly influence the onset and worsening of asthma. Common triggers include:
   • Allergens: Substances like pollen, mold, dust mites, and pet dander can trigger asthma. Allergic asthma is the most prevalent type and usually starts in childhood.
   • Air Pollution: Contact with pollutants like cigarette smoke, car exhaust, industrial toxins, and indoor air pollution (like cooking smoke) can irritate airways and lead to asthma.
   • Respiratory Infections: Viral infections in young children are associated with a higher risk of asthma. Infections like respiratory syncytial virus (RSV) and rhinovirus can make asthma more likely.
   • Occupational Exposures: Coming into contact with dust, chemicals, or fumes at work (in professions such as farming, healthcare, or manufacturing) can lead to occupational asthma.
   • Climate and Weather: Cold temperatures, high humidity, and seasonal changes can worsen asthma symptoms. Weather factors can be especially troublesome for those with exercise-induced asthma.
   • Allergic Reactions: Often, asthma is part of a larger range of allergic diseases including allergic rhinitis, eczema, and food allergies. These conditions frequently occur together, and having one may increase the chance of developing asthma.
3. Lifestyle and Behavioral Factors:
   • Obesity: Being overweight raises the risk of developing asthma because extra weight can cause airway swelling and diminish lung function.
   • Diet: A diet lacking in fruits, vegetables, and antioxidants may heighten asthma risk, while a nutrient-rich diet might alleviate symptoms.
4. Other Factors:
   • Gender: Asthma is more prevalent in children, especially boys. However, adults tend to have more cases among women, possibly owing to hormonal influences.
   • Exercise: Engaging in physical activity, particularly in cold or dry air, may lead to exercise-induced asthma, which can cause worsening symptoms during activity. causes shortness of breath, wheezing, and cough when exercising or afterwards.

Symptoms

Asthma symptoms can be different in severity and change over time. Common asthma symptoms are:

1. Wheezing: Wheezing is a high sound when breathing out, caused by narrowed airways. It is a key symptom of asthma.
2. Shortness of Breath: Asthma may result in trouble breathing, especially during exercise or at night when symptoms can get worse.
3. Coughing: A persistent cough, especially at night or in the morning, is a frequent asthma symptom. The cough is usually dry but can sometimes produce mucus.
4. Chest Tightness: People with asthma might feel tightness in the chest, often described like pressure or squeezing.
5. Increased Mucus Production: Asthma can lead to more mucus in the airways, which can block airflow and make breathing harder.
6. Exercise-induced Symptoms: People with asthma may have worsened symptoms, like coughing, wheezing, or shortness of breath, during or after physical activity, particularly in cold or dry conditions.

Asthma symptoms often come and go, with times of no symptoms followed by flare-ups. These flare-ups can be triggered by allergens, infections, exercise, or emotional stress.

Risk Factors

Several aspects increase the chance of getting asthma or worsening existing symptoms. These are:

1. Family History: A family history of asthma or allergies raises the chance of developing asthma due to genetic factors.
2. Allergic Conditions: Conditions like hay fever, eczema, or food allergies can increase the risk of asthma, especially in children.
3. Environmental Factors: Being exposed to various allergens, air pollution, tobacco smoke, and irritants at work raises the risk of developing asthma or worsening its symptoms.
4. Age: While asthma can occur at any age, it is more frequent in children. However, asthma in adults is also rising, particularly in women.
5. Obesity: Being overweight is a significant risk factor for asthma and can make symptoms worse and treatment less effective.
6. Respiratory Infections: Respiratory infections in young children, especially viral ones like RSV, can increase the risk of getting asthma later.

Differential Diagnosis

Several conditions may show symptoms like asthma, so it is important to distinguish between them. These include:

1. Chronic Obstructive Pulmonary Disease (COPD): COPD is a progressive lung disease often caused by smoking, sharing symptoms like cough, wheezing, and shortness of breath with asthma. However, unlike asthma, COPD is usually not reversible and generally worsens over time.
2. Bronchitis: Acute or chronic bronchitis can cause wheezing and coughing, but is usually connected with a productive cough, which is less common in asthma.
3. Gastroesophageal Reflux Disease (GERD): GERD can result in wheezing, coughing, and chest discomfort, which might look like asthma symptoms. However, GERD symptoms often get worse after eating and when lying down.
4. Vocal Cord Dysfunction (VCD): VCD causes symptoms similar to asthma, including wheezing and trouble breathing, but does not involve airway inflammation. VCD is usually triggered by exercise or stress and is treated differently than asthma.
5. Heart Failure: Lung fluid buildup from heart failure can produce symptoms like shortness of breath and wheezing, necessitating the need to rule out heart failure as a cause. of symptoms that resemble asthma.
6. Infectious Causes: Infections in the respiratory system, like pneumonia or tuberculosis, can cause cough, wheezing, and tightness in the chest, so it’s necessary to differentiate them from asthma.

Investigation

Diagnosing asthma requires clinical assessment, medical history, physical check-up, and tests:

1. Medical History and Physical Examination: Collecting a full history of symptoms, triggers, and any family history of asthma or allergies is important. The doctor looks for signs of blockage in the airways, like wheezing or prolonged expiration.
2. Spirometry: Spirometry is essential in diagnosing asthma. It checks how much air a patient can inhale and exhale and how fast they can exhale. If there’s a noticeable improvement in lung function after using a bronchodilator, it suggests asthma.
3. Peak Flow Measurement: A peak flow meter shows the highest speed of air exhaled. Tracking peak flow can help understand asthma control and spot early indicators of worsening asthma.
4. Methacholine Challenge: Sometimes, a methacholine challenge test is done to cause bronchoconstriction in the airways. This is useful when asthma is suspected but spirometry results are normal.
5. Allergy Testing: Skin or blood tests for allergies can help find triggers for asthma symptoms, especially in those with allergic asthma.
6. Exhaled Nitric Oxide (FeNO) Testing: FeNO testing checks nitric oxide levels in breath, which rises with airway inflammation. This can assess the severity of asthma inflammation and monitor how well treatment is working.
7. Chest X-ray: A chest X-ray helps rule out other causes of symptoms, such as pneumonia, and checks for signs of lung disease or hyperinflation.

Treatment

Managing asthma aims to control symptoms, reduce inflammation, and prevent worsening episodes. Treatment usually involves medications and lifestyle changes.

1. Pharmacological Treatments:

• Short-acting Beta-agonists (SABAs): Drugs like albuterol (Salbutamol) provide quick relief during asthma attacks. These bronchodilators relax airway muscles, improving airflow. SABAs are known as “rescue inhalers” because they act fast.

• Inhaled Corticosteroids (ICS): These are the best long-term treatment for asthma, helping reduce inflammation and prevent worsening symptoms. ICS medications, like fluticasone, budesonide, and beclometasone, are taken daily to manage chronic asthma and avoid attacks. They are often combined with other drugs for better control.

• Long-acting Beta-agonists (LABAs): LABAs, such as salmeterol and formoterol, are used for long-term control, usually alongside inhaled corticosteroids. They help prevent bronchoconstriction by relaxing airway muscles longer. LABAs should not be used without ICS due to a higher risk of worsening asthma.
• Leukotriene Modifiers: Medications like montelukast and zafirlukast limit inflammation by blocking leukotrienes, which cause bronchoconstriction. These are useful for asthma triggered by allergies and exercise.
• Theophylline: This oral drug relaxes airway muscles and enhances airflow. It’s not used often today but may help some cases of difficult asthma.
• Biologic Therapies: For severe asthma that doesn’t respond to regular treatments, biologic therapies, like omalizumab (Xolair), mepolizumab, and benralizumab, target specific molecules involved in inflammation. These treatments are generally given through injections. by injection and can help a lot with controlling asthma for people who have allergic asthma or eosinophilic asthma.
• Oral Corticosteroids: Prednisone and prednisolone are given for short times during asthma flare-ups or for those with bad, uncontrolled asthma. These drugs should be used carefully because long-term use can cause side effects, like osteoporosis and weight gain.

2. Non-Medical Management:

• Allergen Avoidance: Discovering and staying away from things that increase asthma issues, like pollen, dust mites, mold, pet hair, and air pollution, is important in handling asthma. Using air purifiers, cleaning often, and cutting down contact with known allergens can help ease symptoms.
• Weight Management: Keeping a healthy weight is very important because being overweight can make asthma symptoms worse and lessen how well treatments work. Losing weight can help manage asthma better and cut down the number of asthma attacks.
• Exercise: Doing physical activity regularly can build up the muscles used in breathing and improve overall lung health. Still, people with asthma should be careful to avoid exercise-induced asthma, like using a bronchodilator before exercising and steering clear of triggers such as cold air or high-pollution days.
• Quitting Smoking: Smoking is a big irritant to the airways and can make asthma symptoms worse, harm lung function, and raise the chance of serious asthma attacks. Stopping smoking and avoiding secondhand smoke is vital for managing asthma.

3. Asthma Action Plan:

An asthma action plan is a custom document detailing how to track asthma symptoms, manage medications, and react to changes in symptoms or peak flow readings.

It aids those with asthma in taking steps to prevent worsening and enhance their quality of life.

4. Emergency Treatment:

• Rescue Medications: For ones having an asthma attack, rescue meds like short-acting beta-agonists (SABAs) should be used right away to ease symptoms. Sometimes, oral corticosteroids or hospitalization might be needed to handle severe asthma attacks.
• Oxygen Therapy: If asthma flare-ups greatly hinder breathing or drop blood oxygen levels, extra oxygen might be necessary to ensure the body gets enough air.
• Hospitalization: Serious asthma attacks may require hospitalization for urgent care, involving oxygen, intravenous medications, and careful observation.

Prognosis

The outlook for people with asthma differs depending on the severity of the issue, adherence to treatment, and if there are other health problems.

With proper treatment, many people with asthma can live active lives with few symptoms. However, asthma is a long-term condition that needs ongoing care, and symptoms may change over time.

If asthma flare-ups are not managed well, they can lead to long-term issues such as changes to the airways, lower lung function, and a reduced quality of life. Hence, early diagnosis, effective care, and regular check-ups are essential for the best results.

Conclusion

Asthma is a widespread, ongoing respiratory issue that impacts millions globally. It features airway inflammation, bronchoconstriction, and hyperreactivity, leading to symptoms like wheezing, coughing, shortness of breath, and pressure in the chest.

Although asthma cannot be entirely cured, it can be effectively managed with a mix of medications, lifestyle changes, and control of the environment.

The main aims of asthma treatment are to manage symptoms, lower inflammation, and prevent flare-ups, thereby enhancing life quality and reducing the chances of long-term complications.