Asthma FAQs

What is asthma and who does it affect? 

Asthma is a swelling of the airways, usually caused by allergens or other irritants which ultimately causes the airways to narrow and make it difficult to breathe. Asthma affects nearly 262 million people worldwide and accounted for approximately 500,000 deaths in 2019. In adults, symptoms of asthma are more common among people assigned female at birth (AFAB)  than those assigned male at birth (AMAB). Contrastingly, asthma is a leading chronic disease among all children, but particularly boys

Urbanisation is often linked to the increasing prevalence of asthma, where air pollutants caused by industrial activity trigger many sufferers’ symptoms. Although the condition is incurable, many children outgrow serious attacks, and symptoms are manageable with proper treatment. 

What are the signs and symptoms of asthma? 

The symptoms associated with airway narrowing include coughing, wheeziness, shortness of breath, and chest tightness. These discomforts can get worse during exercise, stress, infections, or triggering allergens. An asthma attack occurs when symptoms suddenly increase in severity and breathing becomes especially difficult. These attacks often require emergency medical treatment or access to an inhaler. Prolonged symptoms may cause adverse outcomes in other areas of life, including consistent fatigue, stress, anxiety, depression, and persistent lung infections. 

What are the signs of hyperresponsiveness in asthma? 

Asthma hyperresponsiveness (AHR) occurs when airways become especially sensitive to various stimulants, which can vary person to person. Incidences of AHR can be divided into two types: acute AHR and chronic AHR. Acute AHR occurs when airway cells release histamines as a reaction to pollutants, allergens, or other triggers, causing the swelling and discomfort associated with many asthma attack symptoms. However, chronic AHR occurs after repeated asthma-related inflammation, leading  to the restructuring of the airway wall and the increased persistence of symptoms. Acute AHR events are treatable using Inhaled Corticosteroid Therapy (ICS), however, chronic asthma symptoms become less and less responsive to treatment overtime. Many sufferers of chronic AHR require daily inhaler use in order to alleviate breathing issues. 

How are allergies connected to asthma? What are common asthma attack triggers? 

Being allergic to certain molecules triggers the airway inflammation associated with asthmatic symptoms like chest tightness, coughing, difficulty breathing, and shortness of breath. Many different types of allergies can lead to asthma, but some of the most common are pollen, air pollution, mould, smoke, dust, pet hair, and some chemicals. These molecules are often identified as foreign invaders by the body. As a combative response, airway cells release histamines that cause capillary restriction and swelling. This immunological process is the cause of many allergen-induced asthma attacks. Allergen-related asthma is also often accompanied by other allergic conditions such as eczema or hay fever.

What are some of the main causes of asthma? 

The reason why some people develop asthma and others do not are still widely unknown. However, certain exposures and risk factors may increase your likelihood of developing the condition. First, as previously discussed, having severe allergies can cause asthmatic symptoms. Second, environmental factors may cause childhood-onset asthma, including air pollution, second-hand smoke, and the incidence of a respiratory infection. Third, genetics can also play a part in the development of asthma, as those with a relative suffering from asthma are more likely to be affected themselves. Knowing your triggers and how to avoid them is the best way to keep symptoms at bay, alongside clinical treatments like ICS and anti-inflammatory medicines. 

How do I know what type of asthma I have? 

The best way to determine if you have asthma, or what type you may have, is to speak to your GP who knows your medical history. Many cases of asthma are diagnosed using a chest x-ray or spirometry, a test which measures the level of airflow passing through the lungs. That being said, there are some telltale signs about what type of asthma you may have. First, acute asthma is often accompanied by severe symptoms, like in the case of an attack, and is most often experienced by children with the condition. Contrastingly, chronic asthma is lasting and perhaps not as urgent as sudden attacks. Furthermore, chronic asthma is most often experienced by adult-onset cases but can be managed with treatment. 


  1. Facts about asthma. RN [Internet]. 2001 Mar;64(3):suppl 5–6. Available from: 
  2. Asthma [Internet]. [cited 2021 Nov 8-14]. Available from: 
  3. Asthma [Internet]. [cited 2021 Nov 8-14]. Available from: 
  4. Asthma [Internet]. Cleveland Clinic. [cited 2021 Nov 8-14]. Available from: 
  5. Brannan J, et al. Airway Hyperresponsiveness in Asthma: Mechanisms, Clinical Significance and Treatment [Internet]. Frontiers. 2015 [cited 2021 Nov 8-14]. Available from: 
  6. Meurs H, Gosens R, Zaagsma J. Airway hyperresponsiveness in asthma: lessons from in vitro model systems and animal models. Eur Respir J [Internet]. 2008 Aug;32(2):487–502. Available from:

Kristen Bowles

Masters of Science - MSc Epidemiology Student, London School of Hygiene and Tropical Medicine, England
Kristen graduated as Summa Cum Laude and is now pursuing Masters of Epidemiology in LSHTM.
Experienced in cultural anthropology from the University of St. Andrews, and hopes to continue working in Europe with a special focus on medical mistrust and how these social factors influence health data, equity, and disease spread.

Leave a Reply

Your email address will not be published. Required fields are marked * presents all health information in line with our terms and conditions. It is essential to understand that the medical information available on our platform is not intended to substitute the relationship between a patient and their physician or doctor, as well as any medical guidance they offer. Always consult with a healthcare professional before making any decisions based on the information found on our website.
Klarity is a citizen-centric health data management platform that enables citizens to securely access, control and share their own health data. Klarity Health Library aims to provide clear and evidence-based health and wellness related informative articles. 
Klarity / Managed Self Ltd
Alum House
5 Alum Chine Road
Westbourne Bournemouth BH4 8DT
VAT Number: 362 5758 74
Company Number: 10696687

Phone Number:

 +44 20 3239 9818