What are The Causes of Asthma?

What are The Causes of Asthma?

Asthma is a chronic disease that affects the airways that carry air to and from the lungs, and asthma causes are many. Persons suffering from this chronic condition are said to be asthmatic.

Asthma is characterized by an inflammation and narrowing of the bronchial tubes which are passageways that allow air to enter and leave the lungs. The inflammation makes an asthmatic’s airways exceedingly sensitive to irritations and susceptible to allergic reaction. The narrowing of the airways causes symptoms such as wheezing, tightness in the chest, difficulty in breathing, and coughing. These symptoms mostly occur during the night and early morning in asthmatics.

A person is said to be having an asthma attack when the symptoms are worse than usual, and the symptoms can occur suddenly and can either be mild, moderate, or sometimes severe.

The World Health Organization (WHO) has established that half the cases of asthma are caused by genetic susceptibility of people, that is, asthma runs in families, and the other half of the asthma cases are caused by environmental factors. It must be known that asthma is incurable, but it can be managed with effective treatment from an allergist, and most asthma attacks can be prevented by avoiding the many asthma causes including allergens, stress, illnesses like cold and flu, extreme weather, irritants present in the air, and some medications that trigger asthma attacks.

Causes of Skin Asthma

Skin asthma is medically termed as atopic dermatitis or eczema. This condition is a non-contagious, chronic skin disorder. Skin asthma mostly occurs in children and very rarely in adults. The disease usually occurs in children before the age of 5, and affects girls more commonly than boys.

Whatever be the skin asthma causes, the symptoms of skin asthma start as red, flaky, itchy rashes on the skin which later turn into scaly, leathery patches over time. The other symptoms of skin asthma include extreme dryness along with itching, flakiness, redness, crusting, swelling, cracks, discoloration, white bumps, blisters, and thickening of skin. Leakage of fluids from certain spots on the skin, and discharge from the ears are some other symptoms.

Skin asthma is mainly a genetic disorder, and the asthma cause is primarily due to an inherited defect in the skin barrier. The imperfection in the protective skin barrier causes the skin to become more permeable and reduces its antimicrobial property.

Some of the Skin Asthma Causes that Trigger skin Irritation and Swelling Include:

  • Chemical irritants such as soaps, perfumes, hair dyes, detergents etc.
  • Air-borne allergens including pollen, dust and dust mites, mold, pet dander etc.
  • Certain foods that trigger allergic reactions such as egg, shrimp, chocolate, peanut etc.
  • Certain fabrics like wool or synthetic fibers
  • Extreme changes in temperature including very hot or very cold conditions
  • The exposure of skin to cold and dry hair
  • Illnesses such as the common cold or flu
  • Emotional stress
  • Sunburns
  • Increased perspiration caused due to exercise
  • Cigarette smoke

Bronchial Asthma Causes

Bronchial asthma is a condition characterized by the inflammation and narrowing of the airways that lead to the lungs. The inflammation in the airways causes excess mucus production that makes breathing difficult and causes coughing, shortness of breath, and wheezing. This disease is chronic and interferes with the daily routine of the persons suffering from the condition. Bronchial asthma can occur at any age and in both the genders, and the bronchial asthma causes mainly include environmental and hereditary factors. Inhalers are the main types of medication that help people overcome an asthma attack, and if the disease is ignored, it can prove fatal to the patient and even claim their life. The root cause of bronchial asthma is still unclear, but the asthma causes are believed to be environmental or genetic factors.

Below are some factors that trigger a bronchial asthma attack:

  • Exposure to allergens such as animal fur, pollen, dust, sand and bacteria
  • Viral infections such as cold and flu and pneumonia
  • Smoke and fumes from vehicles and air pollution
  • Mental stress and anxiety
  • Acid reflux or the gastroesophageal reflux disease (GERD)
  • Asthma induced by excess physical activity or exercise
  • Weather changes including extreme changes in temperature
  • Medications such as aspirin, ibuprofen, and beta-blockers
  • Food additives such as MSG

Causes of Occupational Asthma

Occupational asthma is defined as the type of asthma caused by exposure to a certain substance in the workplace. Occupational asthma is usually differentiated into two types: immune-mediated asthma and irritant-induced asthma. Immune-mediated asthma occurs when a person is exposed to an agent in the workplace that stimulates the body’s immune system which then triggers an asthma attack. In immune-mediated occupational asthma, there is a latency period between the exposure to the irritant at the workplace and the occurrence of symptoms; the latency period may be from a few weeks to several years. In irritant-induced occupational asthma, the agent directly irritates the airways and causes symptoms to occur immediately after exposure to the irritant.

There are various substances used in different industries that are known to be occupational asthma causes or sometimes trigger an asthma attack. These include:

  • Chemicals such as adhesives, lacquer, plastics, epoxy resins, foam, rubber, dyes used in the textile industry and enzymes used to manufacture detergents
  • Proteins present in animal hair or fur and animal dander
  • Certain grains, green coffee beans, and papain which is an extract of papaya that sometimes triggers a latex allergy
  • Cotton, flax, and hemp dust which are commonly found in textile manufacturing units
  • Metals like platinum, chromium, nickel sulfate, and the fumes that occur from soldering

Childhood Asthma Causes

Asthma has been found to be the leading cause of chronic illness in children. Asthma can begin at any age, including in the very elderly, but most children show symptoms of the disease before the age of 5. Asthma episodes account for the majority of emergency department visits and hospitalization in children below 18 years of age, and asthma causes children to miss school. It accounts for more school absences than any other chronic illness. Symptoms of childhood asthma include frequent coughing spells especially in the night or during playtime, wheezing, intermittent rapid breathing, shortness or loss of breath, feelings of chest tightness, and complaints of feeling tired.

While a family history of asthma or allergies makes a child more prone to asthma, other childhood asthma causes and the risk factors for developing childhood asthma include:

  • Nasal allergies such as hay fever
  • Skin allergies such as eczema
  • Frequent respiratory infections during infancy and childhood
  • Low birth weight
  • Recurring viral infections
  • Early exposure to tobacco smoke
  • Environmental pollutants such as automobile emissions
  • Exposure to allergens such as molds, fungi, pet dander, pollen, and dust mites
  • Irritants such as perfumes, paint odors, and hair sprays
  • Weather changes including factors such as temperature changes and changes in the humidity and quality of air
  • Any factors that cause emotional stress in children
  • The use of drugs such as acetaminophen

Since infants and toddlers do not know how to express the way they feel, parents and other care-givers should keep an eye out for any symptoms that point to an asthma attack in children who are prone to it. Parents should let the pediatrician know if there is a family history of asthma or any other allergies such as hay fever, hives, or eczema, since children born into such families are more likely to develop asthma or the other types of allergy mentioned earlier.

Medically Reviewed By
Dr. Kaushal M. Bhavsar (MBBS, MD)Assistant Professor in Pulmonary Medicine, GMERS Medical College, Ahmedabad