What is emphysema?
Emphysema is a type of Chronic Obstructive Pulmonary Disease. This type of COPD happens when there is damage to the lungs’ air sacs (alveoli). Through time the air scas walls become weakened, which might collapsed, destroyed, narrowed, overinflated or stretched.1,2
This damage reduces the surface area available to change the gases (oxygen and carbon dioxide) in the lungs; therefore, less oxygen reaches the bloodstream. When the alveoli become overinflated, the air exhaled stays trapped, and there is no room for the air rich in oxygen to come in.1,3
Treatment can make the progression of the disease slower. However, the damage is not reversible.
Symptoms
The main symptoms of emphysema are:
- Shortness of breath – getting breathless on exertion or even at rest.
- Persistent cough – cough that does not resolve with time and gets worse.
- Regular sputum production – clear when non-infective and yellow/green when associated with infection.
- Recurrent lung infection – due to the difficulty of clearing up bacteria and viruses in the airway.
- Wheeze – the narrowing of the airway can cause wheeze.
These symptoms are the main ones and tend to be progressive over time. There are some less common symptoms, which include:
- Weight loss – due to burning a lot of energy in the effort to breathe appropriately and reduced appetite caused by changes in the body.
- Reduced exercise tolerance – a limited amount of things that can be done without shortness of breath or a limited amount of time doing things without feeling breathless.
- Ankle swelling – due to heart problems caused by increased pulmonary pressure.
- Chest pain – caused by different types of damage in the lungs or even as a result of heart problems caused by emphysema.
- Coughing up blood – caused by the rupture of the vessels.4,5
Causes
Emphysema is caused by long-term inflammation of the airways, mainly the alveoli, caused by exposure to harmful particles and gases. The leading causes are:
- Smoking: a most common risk factor of chronic obstructive lung disease, associated with 90% of cases.
- Occupational exposure: to dust, fumes and chemicals; around 20% of the cases are related to this.
- Genetics: less common when compared to the others, but obstructive lung disease is associated with alpha-1-antitrypsin protein deficiency.
- Air pollution: still not conclusive, but some research has shown potential increased risk.
- Lung development: factors involving lung growth and development can potentially increase the risk of COPD, but research regarding the matter continues.
- Asthma: a recent study showed a higher risk for patients with asthma to develop COPD.6
Below we will talk more about the three leading causes of this disease
Smoking
This is the leading cause of emphysema. As explained above, the lung air sacs are the structures this disease affects. They are formed by very thin and fragile walls full of small blood vessels, where the exchange of oxygen and carbon dioxide takes place.
When the alveoli are exposed, for a long term, to the toxic substances of tobacco, the process caused by the deposit of this toxin and inflammation of the lung tissue culminate in the destruction of the walls of the sacs, the ones that are not destroyed end up losing its elasticity forming a tissued scar.
This process affects the exchange of gases and imprisons the air inside the lungs, preventing the air rich in oxygen from achieving the bloodstream.7,8
Exposure to toxic fumes
Some other substances like industrial chemicals, dust, and construction debris are also associated with emphysema. The implications that have been related to it are:
- Cadmium dust and fumes
- Grain and flour dust
- Silica dust
- Welding fumes
- Isocyanates
- Coal dust
The way these substances affect the lungs is very similar to tobacco, and workers that are exposed to these needs to be aware of the risks and protect themselves with appropriate PPE.9
Alpha 1-antitrypsin (AAT) deficiency
This genetic cause is rare and responsible for 1% of the causes in people with Chronic Obstructive Pulmonary Disease.
In this disease, the production of the protein called Alpha 1-antitrypsin is reduced. This protein helps to protect the lung tissue from being damaged by external aggression, and therefore its low levels can lead to lung disease.
This is a genetic disorder that cannot be prevented, and it is inherited. Generally, people who suffer from AAT deficiency present COPD from a younger age.9,10
Summary
Emphysema is a type of Chronic Obstructive Lung Disease where there is damage to the air sacs of the lungs (alveoli), causing them to be destroyed or lose their elasticity.
This affects the blood gases exchange and less oxygen reaches the bloodstream, which is also inflamed, causing symptoms like breathlessness, cough, sputum production, recurrent lung infections and wheezing. The leading cause of emphysema is smoking since the toxins are directly responsible for the damage to the alveoli, but other harmful substances like toxic fumes are also related. One less common cause is the Alpha 1-antitrypsin deficiency, when this protein responsible for protecting the lung tissue is reduced in the bloodstream leading to lung disease.
It is essential to say that emphysema is a progressive disease that doesn’t have a cure but can be managed with the proper treatment, and its progression can be slowed down.
References
- Emphysema - Symptoms and causes [Internet]. Mayo Clinic. [cited 2022 Aug 15]. Available from: https://www.mayoclinic.org/diseases-conditions/emphysema/symptoms-causes/syc-20355555
- Pulmonary emphysema [Internet]. 2019 [cited 2022 Aug 15]. Available from: https://www.hopkinsmedicine.org/health/conditions-and-diseases/pulmonary-emphysema
- Emphysema [Internet]. [cited 2022 Aug 15]. Available from: https://www.lung.org/lung-health-diseases/lung-disease-lookup/emphysema
- CKS is only available in the UK [Internet]. NICE. [cited 2022 Aug 15]. Available from: https://www.nice.org.uk/cks-uk-only
- Chronic obstructive pulmonary disease (Copd) - Symptoms [Internet]. NHS.uk. 2018 [cited 2022 Aug 15]. Available from: https://www.nhs.uk/conditions/chronic-obstructive-pulmonary-disease-copd/symptoms/
- CKS is only available in the UK [Internet]. NICE. [cited 2022 Aug 15]. Available from: https://www.nice.org.uk/cks-uk-only
- Song Q, Chen P, Liu XM. The role of cigarette smoke-induced pulmonary vascular endothelial cell apoptosis in COPD. Respiratory Research [Internet]. 2021 Feb 5 [cited 2022 Aug 16];22(1):39. Available from: https://doi.org/10.1186/s12931-021-01630-1
- COPD - Symptoms and causes [Internet]. Mayo Clinic. [cited 2022 Aug 16]. Available from: https://www.mayoclinic.org/diseases-conditions/copd/symptoms-causes/syc-20353679
- Chronic obstructive pulmonary disease (Copd) - Causes [Internet]. nhs.uk. 2018 [cited 2022 Aug 16]. Available from: https://www.nhs.uk/conditions/chronic-obstructive-pulmonary-disease-copd/causes/
- Learn about alpha-1 antitrypsin deficiency [Internet]. [cited 2022 Aug 16]. Available from: https://www.lung.org/lung-health-diseases/lung-disease-lookup/alpha-1-antitrypsin-deficiency/learn-about-alpha-1-antitrypsin-defiency