Causes and Risk Factors of Asthma (2022)

Though asthma is common, what causes it isn't fully understood. It's likely there is a genetic component that predisposes a person to develop the disease, but typically certain environmental factors must also be in place.

But although experts may not know for sure why one person has asthma and another doesn't, they do understand the changes in the body that lead to asthma symptoms—bronchoconstriction (narrowing of the bronchi, or airways) and excess mucus production that together restrict airflow.

There also are a variety of known risk factors for asthma, such as excess weight, as well as many common triggers ranging from allergens like dust mites and mold to exercise and respiratory infections such as a common cold.

This article describes what's currently known about the risk factors for asthma.

Causes and Risk Factors of Asthma (1)

Risk Factors for Asthma

You are at an increased risk of having asthma if you:

  • Have a family history of asthma
  • Had certain types of viral respiratory infections as a baby or young child
  • Have eczema (atopic dermatitis) or allergies, such as hay fever (allergic rhinitis)
  • Are exposed to dust or chemical fumes in your work
  • Currently smoke or did in the past, your mother smoked while pregnant with you, or you've been exposed to secondhand smoke
  • Have been exposed to air pollution (specifically ozone)
  • Are overweight, which can lead to worse symptoms and less effective control of the condition
  • Were born prematurely or had a low birth weight

Among children, asthma is more common in males than females. By adulthood, this is reversed, and females are more likely to have asthma.

Asthma Disparities

Racial and ethnic minority groups experience a disproportionate burden of asthma. Black and Latinx people and American Indian/Alaska Natives are more likely to develop asthma compared to White Americans. Puerto Ricans have particularly high rates of asthma, nearly twice that of non-Hispanic Whites.

Black Americans are five times more likely to be hospitalized for asthma compared to White Americans, and three times as likely to die from it. Black women have the highest risk of death from asthma of all groups.

The reasons for these disparities are varied and include less access to health care, poorer quality care, increased exposure to indoor and outdoor triggers, and higher levels of stress.

Atopic March

Infants who have atopic dermatitis sometimes go on to develop hay fever and asthma—especially if they experienced wheezing as babies. This phenomenon is referred to as atopic march or progressive atopy.

It's thought that the barrier that skin usually provides against allergy-triggering substances (allergens) is less effective in children with eczema, allowing them to become sensitized.

Genetics

It is well-established that asthma runs in families, which suggests that the condition has a significant genetic component. More than 100 genes have been associated with allergic asthma, most of which are involved in immune reactions and lung functions.

However, the presence of any of these genes in a person's DNA does not guarantee they will have asthma; it only means they're at an increased risk. It typically requires exposure to an environmental trigger for asthma to develop.

You are three to six times more likely to have asthma if one of your parents has asthma, according to the American Lung Association.

(Video) Asthma - causes, symptoms, diagnosis, treatment, pathology

Asthma Triggers

The potential causes of asthma symptoms and asthma attacks in those who have the condition are as variable and unique to each individual as are the factors that put them at risk in the first place. There's a wide variety of such triggers, and many people have more than one.

Indoor Triggers

Your home may harbor any of several common allergens known to bring on asthma symptoms.

  • Dust mites: Dust mites (Dermatophagoides pteronyssinus) are microscopic insects that exist in every home and feed on tiny flakes of skin and hair found on bedding (mattresses, pillows, bed covers), carpets, upholstered furniture or anything covered in fabric, and stuffed toys.
  • Mold: Mold is most often found on wet or damp surfaces in bathrooms, kitchens, and basements.
  • Cockroaches and other pests: Body parts, urine, and droppings of cockroaches and pests contain proteins that can trigger allergy symptoms.
  • Pets: Allergens from your pets' dead skin, droppings, urine, and saliva can trigger asthma.
  • Secondhand smoke: Environmental tobacco smoke contains more than 250 different chemicals, including benzene, vinyl chloride, and arsenic, that may irritate airways and bring on asthma symptoms.
  • Nitrogen dioxide: Nitrogen dioxide is a gas released by gas stoves, fireplaces, and gas space heaters. It can irritate lungs and lead to shortness of breath.

Outdoor Triggers

During the spring and fall, airborne pollens and molds commonly trigger asthma symptoms, among them:

  • Pollen: Pollens are small, powdery granules that are essential for plant fertilization. Pollens from many different kinds of grasses, weeds, and trees may trigger allergy and asthma symptoms. The season and weather conditions greatly influence the amount of pollen in the air. Pollen season varies depending on location but typically lasts from February to October.
  • Mold: Mold growing in soil or on outdoor vegetation can become airborne and trigger asthma symptoms.
  • Weather: Certain weather conditions can make asthma triggers more problematic. Pollen is particularly plentiful when it's hot, dry, and windy outside, for example. Mold thrives in rainy or humid weather. Dry, cold, or windy weather can also set off asthma episodes.

Respiratory Infections

Any type of respiratory infection—such as a common cold or the flu—can trigger asthma symptoms. If you have asthma, it's especially important to take measures to stay well:

  • Wash your hands frequently
  • Don't touch your nose or mouth while you're out in public or around someone who's sick
  • Get a flu shot every year.

Why You Need a Flu Shot If You Have Asthma

Less Common Asthma Triggers

Although these triggers are relatively uncommon, they are potentially serious for people who are sensitive to them.

  • Medications: A number of different medications are associated with asthma flare-ups, including pain medications (aspirin, ibuprofen, naproxen) and beta-blockers.
  • Food allergies: Some foods like fish, soy, eggs, wheat, and tree nuts are common food allergens. In some patients with life-threatening food allergies, eating these foods can also trigger asthma attacks, which can be deadly.
  • Exercise: Wheezing, coughing, and chest pain can occur in response to physical activity in people with asthma. This is known as exercise-induced bronchoconstriction (EIB) and is most common in teens and young adults.

What Is Exercise-Induced Asthma?

Summary

The exact cause of asthma isn't well understood, but it's thought that a combination of genetic predisposition and exposures during life play a role. Asthma symptoms occur when an immune reaction causes airway constriction and excess mucus production, which together interfere with breathing.

Risk factors include a family history of asthma, exposure to tobacco smoke and other chemicals, dust, or fumes, and respiratory infections early in life. Many triggers can set off asthma symptoms, such as pollen, exercise, and food allergies.

A Word From Verywell

There's no cure for asthma, but it can be managed. Identifying the triggers that cause you to have symptoms and, with the help of your healthcare provider, coming up with an asthma action plan that reduces your exposure to them, is key. Doing so may also reduce your need for medication.

Frequently Asked Questions

  • Does smoking cause asthma?

    Yes, smoking and exposure to cigarette smoke have been linked to the development of asthma at all ages. Asthma can develop in adults who smoke: In one large study, adult women smokers had a 40% higher risk of developing asthma.

    (Video) Risk Factors for Asthma - John R. Balmes MD

  • Does air pollution cause asthma?

    Yes. Pollution is linked to developing asthma and experiencing worse asthma symptoms. Estimates suggest that 13% of children’s asthma is caused by traffic-related air pollution.

  • What is the most common cause of an asthma attack?

    The common cold is the most frequent cause of an asthma attack in both children and adults. In fact, asthma exacerbations that send people to the hospital are highest in the spring and autumn—at the height of cold season.

How Asthma Is Diagnosed

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(Video) Risk Factors of Asthma

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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

  1. Kudo M, Ishigatsubo Y, Aoki I. Pathology of asthma. Front Microbiol. 2013;4:263.doi:10.3389/fmicb.2013.00263

  2. American Lung Association. Asthma risk factors.

  3. Mohanan S, Tapp H, McWilliams A. Obesity and asthma: Pathophysiology and implications for diagnosis and management in primary care. Exp Biol Med (Maywood). 2014;239(11):1531-40. doi:10.1177/1535370214525302

  4. UK National Health Service. Asthma causes.

  5. National Heart, Lung, and Blood Institute. Asthma risk factors.

  6. American Lung Association. Current asthma demographics.

  7. Asthma and Allergy Foundation of America. Asthma disparities in America.

  8. Bantz SK, Zhu Z, Zheng T. The atopic march: Progression from atopic dermatitis to allergic rhinitis and asthma. J Clin Cell Immunol. 2014 Apr;5(2):202. doi:10.4172/2155-9899.1000202

    (Video) Asthma, Animation.

  9. Thomsen SF. Genetics of asthma: An introduction for the clinician. Eur Clin Respir J. 2015;2. doi:10.3402/ecrj.v2.24643

  10. Fassio F, Guagnini F. House dust mite-related respiratory allergies and probiotics: A narrative review. Clin Mol Allergy. 2018;16:15. doi:10.1186/s12948-018-0092-9

  11. Do DC, Zhao Y, Gao P. Cockroach allergen exposure and risk of asthma. Allergy. 2016;71(4):463-74. doi:10.1111/all.12827

  12. Belanger K, Holford TR, Gent JF, et al. Household levels of nitrogen dioxide and pediatric asthma severity. Epidemiology. 2013;24(2):320-30. doi:10.1097/EDE.0b013e318280e2ac

  13. Locksley RM, Fahy JV. Asthma and the flu: A tricky two-step. Immunol Cell Biol. 2014;92(5):389-91. doi:10.1038/icb.2014.24

  14. Lo PC, Tsai YT, Lin SK, Lai JN. Risk of asthma exacerbation associated with nonsteroidal anti-inflammatory drugs in childhood asthma: A nationwide population-based cohort study in Taiwan. Medicine (Baltimore). 2016;95(41):e5109. doi:10.1097/MD.0000000000005109

  15. Del Giacco SR, Firinu D, Bjermer L, et al. Exercise and asthma: An overview. Eur Clin Respir J. 2015;2:27984. doi:10.3402/ecrj.v2.27984

  16. Royal C, Gray C. Allergy prevention: An overview of current evidence. Yale J Biol Med. 2020 Dec 29;93(5):689-698. PMID: 33380931

  17. Coogan PF, Castro-Webb N, Yu J, O'Connor GT, Palmer JR, Rosenberg L. Active and passive smoking and the incidence of asthma in the Black Women's Health Study. Am J Respir Crit Care Med. 2015;191(2):168-176. doi:10.1164/rccm.201406-1108OC

  18. Tiotiu AI, Novakova P, Nedeva D, et al. Impact of air pollution on asthma outcomes. Int J Environ Res Public Health. 2020;17(17):6212. doi:10.3390/ijerph17176212

  19. Castillo JR, Peters SP, Busse WW. Asthma exacerbations: Pathogenesis, prevention, and treatment. J Allergy Clin Immunol Pract. 2017 July-August; 5(4): 918–927. doi: 10.1016/j.jaip.2017.05.001

Additional Reading

FAQs

What are the main causes of asthma? ›

Common triggers include:
  • infections like colds and flu.
  • allergies – such as to pollen, dust mites, animal fur or feathers.
  • smoke, fumes and pollution.
  • medicines – particularly anti-inflammatory painkillers like ibuprofen and aspirin.
  • emotions, including stress, or laughter.

What is the cause and effect of asthma? ›

Asthma is a chronic condition that affects the airways. It causes wheezing and can make it hard to breathe. Some triggers include exposure to an allergen or irritant, viruses, exercise, and emotional stress. Asthma causes the inside walls of the airways, or the bronchial tubes, to become swollen and inflamed.

What are causes and risk factors? ›

Risk Factors versus Causes

Epidemiologists often use the term "risk factor" to indicate a factor that is associated with a given outcome. However, a risk factor is not necessarily a cause. The term risk factor includes surrogates for underlying causes.

What are risk factors for asthma in children? ›

Risk factors

Factors that might increase your child's likelihood of developing asthma include: Exposure to tobacco smoke, including before birth. Previous allergic reactions, including skin reactions, food allergies or hay fever (allergic rhinitis) A family history of asthma or allergies.

What are the causes of asthma class 12 physical education? ›

Asthma Causes
  • Respiratory infections caused by the common cold.
  • Dust and dust mites.
  • Pet dander.
  • Pollution.
  • Vehicular and industrial exhaust.
  • Medication.
  • Pollen.
  • Smoking.
Jul 29, 2019

What are the 3 types of asthma? ›

Types of asthma
  • Difficult to control asthma.
  • Severe asthma.
  • Occupational asthma.

What is the effects of asthma? ›

Asthma is a disease that affects the airways of your lungs. With asthma, your airways' lining tends to always be in a hypersensitive state characterized by redness and swelling (inflammation). It's similar to how your skin becomes red, irritated and sensitive after a sunburn.

What is asthma PDF? ›

Asthma is a common chronic lung disease in which the airways (bronchi) become inflamed and are abnormally sensitive to certain triggers. Asthma can affect people of all races and ages, and although there is no known cure, there are many ways to control it.

What are the types of asthma? ›

What are the different types of asthma?
  • Allergic asthma.
  • Nonallergic asthma.
  • Seasonal asthma.
  • Occupational asthma.
  • Exercise-induced asthma.
  • Difficult-to-control asthma.
  • Severe asthma.
  • Summary.
Apr 28, 2020

What causes asthma in elderly? ›

When asthma does occur at a later age, the symptoms are much like those experienced by anyone else. The most common causes of an asthma flare up are a respiratory infection or virus, exercise, allergens, and air pollution (an irritant). Allergens and irritants are substances found in our everyday environment.

Who's at risk for asthma? ›

Overweight adults with a body mass index (BMI) between 25 and 30 are 38 percent more likely to have asthma. Obese adults with a BMI of 30 or higher have twice the risk of asthma. Stress. People who consistently experience stress or anxiety have higher asthma rates.

What are modifiable risk factors for asthma? ›

In the United States, a significant proportion of childhood asthma may be attributable to modifiable risk factors including acute viral respiratory infections, antibiotic use, birth by cesarean section, obesity, second hand smoke exposure, and allergen sensitization.

How can you reduce the risk of getting asthma? ›

Tips for Asthma Prevention
  1. Identify Asthma Triggers.
  2. Stay Away From Allergens.
  3. Avoid Smoke of Any Type.
  4. Prevent Colds.
  5. Allergy-Proof Your Home.
  6. Get Your Vaccinations.
  7. Consider Immunotherapy Allergy Shots.
  8. Take Asthma Medications as Prescribed.
Jun 1, 2021

What are the causes of risk? ›

The main causes of business risk are as under:
  • Natural Factors. There are certain nature factors like floods, earthquake etc. ...
  • Competition. ...
  • Change in demand for the product. ...
  • Use of Modern Technology. ...
  • Human Causes of Business Risk. ...
  • Change in Government Policies. ...
  • Mismanagement.

What are the 4 types of risk factors? ›

Risk factors in health and disease
  • Behavioural.
  • Physiological.
  • Demographic.
  • Environmental.
  • Genetic.

Is gender a risk factor for asthma? ›

A gender disparity exists in asthma prevalence. As adults, women have an increased asthma prevalence compared to men. Further, women are more likely to have severe asthma and a later onset of asthma compared to men.

What is the risk factor of allergy? ›

Abstract. Host factors involved in the risk for allergy are heredity, sex, race and age, with heredity being by far the most important. Exposure to allergens has been identified as an influential environmental factor, whereas passive smoking and pollution may act as an adjuvant.

Which child is at greatest risk for asthma? ›

Boys are more likely to develop childhood asthma, as compared with girls, at least until the point of puberty. This has been explained by smaller airway size in boys compared with girls under age 10 years, which predisposes to worsened airway reactivity, as compared with girls of the same age, height and weight (21).

What is asthma class 11th? ›

Asthma is a common long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms like reversible airflow obstruction and bronchospasm. Symptoms include wheezing, coughing, chest tightness and shortness of breath.

What is asthma class 11 Ncert? ›

Asthma is a difficulty in breathing causing wheezing due to inflammation of bronchi and bronchioles.

What are the major causes of disorders Class 12? ›

There are various factors underlying Abnormal Behaviour according to Psychological Disorders Class 12:
  • Biological Model. ...
  • Genetic Model. ...
  • Psychological Model. ...
  • Trauma and Stress- Related Disorder. ...
  • Formal Thought Disorders.
Sep 3, 2021

What are the 4 types of asthma? ›

The four main categories of asthma, a chronic respiratory disease that makes it difficult to breathe, are intermittent, mild persistent, moderate persistent, and severe persistent.

What are the 4 types of asthma triggers? ›

The most common asthma triggers include:
  • Allergies (Allergic Asthma) Substances that cause allergies (allergens) can trigger asthma. ...
  • Irritants in the Air. Irritants in the environment can also bring on an asthma episode. ...
  • Other Health Conditions. ...
  • Exercise. ...
  • Weather. ...
  • Feeling and Expressing Strong Emotions. ...
  • Medicines.

Is asthma a disease? ›

Asthma is a major noncommunicable disease (NCD), affecting both children and adults, and is the most common chronic disease among children. Inflammation and narrowing of the small airways in the lungs cause asthma symptoms, which can be any combination of cough, wheeze, shortness of breath and chest tightness.

What is asthma notes? ›

Asthma is a condition in which your airways narrow and swell and may produce extra mucus. This can make breathing difficult and trigger coughing, a whistling sound (wheezing) when you breathe out and shortness of breath. For some people, asthma is a minor nuisance.

What is asthma introduction? ›

Asthma is a chronic inflammatory lung disease that can cause repeated episodes of cough, wheezing and breathing difficulty. During an acute asthma episode, the airway lining in the lungs becomes inflamed and swollen. In addition, mucus production occurs in the airway and muscles surrounding the airway spasm.

What is asthma Slideshare? ›

DEFENITION • Asthma is a common chronic inflammatory disease of the airways characterized by recurent and reversible episodes of airflow obstruction and bronchospasm. • Common symptoms include wheezing, coughing, chest tightness, and shortness of breath.

What is type2 asthma? ›

Type 2 asthma is characterised by Type 2 inflammation and typically includes allergic asthma, exercise-induced asthma, and late-onset eosinophilic asthma. Understanding of allergic, eosinophilic, and mixed allergic/eosinophilic phenotypes has greatly advanced and may underpin new approaches to improve asthma control.

What causes non allergic asthma? ›

Nonallergic asthma develops when something other than an allergen triggers the immune system to respond by releasing antibodies that cause inflammation. Intrinsic or nonallergic asthma can be caused by: Cold or dry air. Heat and humidity.

Is asthma an allergy? ›

When allergies combine with a breathing condition called asthma, it's called allergic asthma. A type of asthma, allergic asthma is a condition where your airways tighten when you breathe in an allergen. This can be something in the air — often pollen, dander or mold spores.

Who is at risk of getting asthma? ›

Overweight adults with a body mass index (BMI) between 25 and 30 are 38 percent more likely to have asthma. Obese adults with a BMI of 30 or higher have twice the risk of asthma. Stress. People who consistently experience stress or anxiety have higher asthma rates.

What is a risk factor for a disease? ›

FAK-ter) Something that increases the chance of developing a disease. Some examples of risk factors for cancer are age, a family history of certain cancers, use of tobacco products, being exposed to radiation or certain chemicals, infection with certain viruses or bacteria, and certain genetic changes.

What are the 3 types of asthma? ›

Types of asthma
  • Difficult to control asthma.
  • Severe asthma.
  • Occupational asthma.

What are the risk factors of Allergy? ›

Common allergy triggers include:
  • Airborne allergens, such as pollen, animal dander, dust mites and mold.
  • Certain foods, particularly peanuts, tree nuts, wheat, soy, fish, shellfish, eggs and milk.
  • Insect stings, such as from a bee or wasp.
  • Medications, particularly penicillin or penicillin-based antibiotics.
Aug 4, 2020

What gene causes asthma? ›

The ORMDL3 gene, in particular, was associatedwith childhood onset, whereas the HLA-DQ gene was related to later-onset asthma. Further, the results showed that 38% of all cases of childhood-onset asthma were attributable to a combination of the identified genes.

How can you reduce the risk of getting asthma? ›

Tips for Asthma Prevention
  1. Identify Asthma Triggers.
  2. Stay Away From Allergens.
  3. Avoid Smoke of Any Type.
  4. Prevent Colds.
  5. Allergy-Proof Your Home.
  6. Get Your Vaccinations.
  7. Consider Immunotherapy Allergy Shots.
  8. Take Asthma Medications as Prescribed.
Jun 1, 2021

What are the 4 types of risk factors? ›

Risk factors in health and disease
  • Behavioural.
  • Physiological.
  • Demographic.
  • Environmental.
  • Genetic.

What are the risk? ›

Risk is the chance or probability that a person will be harmed or experience an adverse health effect if exposed to a hazard. It may also apply to situations with property or equipment loss, or harmful effects on the environment.

What are the 4 types of asthma? ›

The four main categories of asthma, a chronic respiratory disease that makes it difficult to breathe, are intermittent, mild persistent, moderate persistent, and severe persistent.

What are the 4 types of asthma triggers? ›

The most common asthma triggers include:
  • Allergies (Allergic Asthma) Substances that cause allergies (allergens) can trigger asthma. ...
  • Irritants in the Air. Irritants in the environment can also bring on an asthma episode. ...
  • Other Health Conditions. ...
  • Exercise. ...
  • Weather. ...
  • Feeling and Expressing Strong Emotions. ...
  • Medicines.

Is asthma a disease? ›

Asthma is a major noncommunicable disease (NCD), affecting both children and adults, and is the most common chronic disease among children. Inflammation and narrowing of the small airways in the lungs cause asthma symptoms, which can be any combination of cough, wheeze, shortness of breath and chest tightness.

What are modifiable risk factors for asthma? ›

In the United States, a significant proportion of childhood asthma may be attributable to modifiable risk factors including acute viral respiratory infections, antibiotic use, birth by cesarean section, obesity, second hand smoke exposure, and allergen sensitization.

How does environment affect asthma? ›

A wide range of indoor and outdoor allergens, irritants, as well as cold temperatures, can exacerbate asthma. Household exposures to dust mites and cockroach allergens, and the irritant effects of environmental tobacco smoke, contribute significantly to asthma morbidity.

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