Chronic obstructive pulmonary disease, or COPD, describes a group of lung conditions that make it difficult to empty air out of the lungs because the airways have become narrowed.

See also Asthma

On this page:

What does COPD stand for?

Chronic= it’s a long-term condition and does not go away
Obstructive= your airways are narrowed, so it’s harder to breathe out quickly and air gets trapped in your chest
Pulmonary= it affects your lungs
Disease= it’s a medical condition Two of these lung conditions are long-term (or chronic) bronchitis and emphysema, which can often occur together.

  • Bronchitis means the airways are inflamed and narrowed. People with bronchitis often produce sputum, or phlegm.
  • Emphysema affects the tiny air sacs at the end of the airways in your lungs, where oxygen is taken up into your bloodstream. They break down and the lungs become baggy and full of bigger holes which trap air.

These conditions narrow the airways. This makes it harder to move air in and out as you breathe, and your lungs are less able to take in oxygen and get rid of carbon dioxide.


The airways are lined by muscle and elastic tissue. In a healthy lung, the springy tissue between the airways acts as packing and pulls on the airways to keep them open.


With COPD, the airways are narrowed because:

  • the lung tissue is damaged so there is less pull on the airways
  • mucus blocks part of the airway
  • the airway lining becomes inflamed and swollen

There aretreatmentsto help you breathe more easily and help you keep active, so it’s important to get an early diagnosis.

What causes COPD?COPD usually develops because of long-term damage to your lungs from breathing in a harmful substance, usually cigarette smoke, as well as smoke from other sources and air pollution. Jobs where people are exposed to dust, fumes and chemicals can also contribute to developing COPD.

You’re most likely to develop COPD if you’re over 35 and are, or have been, a smoker or had chest problems as a child.

Some people are more affected than others by breathing in noxious materials. COPD does seem to run in families, so if your parents had chest problems then your own risk is higher.

A rare genetic condition calledalpha-1-antitrypsin deficiencymakes people very susceptible to developing COPD at a young age.

What’s the difference between COPD and asthma?

With COPD, your airways have become narrowed permanently – inhaled medication can help to open them up to some extent. With asthma, the narrowing of your airways comes and goes, often when you’re exposed to a trigger – something that irritates your airways – such as dust, pollen or tobacco smoke. Inhaled medication can open your airways fully, prevent symptoms and relieve symptoms by relaxing your airways.So, if your breathlessness and other symptoms are much better on some days than others, or if you often wake up in the night feeling wheezy, it may be that you have asthma.Because the symptoms are similar and because people who have asthma as children can develop COPD in later life, it is sometimes difficult to distinguish the two conditions. Some people have both COPD and asthma.


What are the symptoms of COPD?

Symptoms include:

  • getting short of breath easily when you do everyday things such as going for a walk or doing housework
  • having a cough that lasts a long time
  • wheezing in cold weather
  • producing more sputum or phlegm than usual

You might get these symptoms all the time, or they might appear or get worse when you have an infection or breathe in smoke or fumes.

If you have COPD that has a severe impact on your breathing, you can lose your appetite, lose weight and find that your ankles swell.

Studies/papers

2023: Health impact of e-cigarettes and heated tobacco products in chronic obstructive pulmonary disease: Current and emerging evidence Morjaria JB, Campagna D, Caci G, O'Leary R, Polosa R. doi: 10.1080/17476348.2023.2167716. Epub ahead of print. PMID: 36638185.

  • Compared with conventional cigarettes, HTPs and ECs offer substantial reduction in exposure to toxic chemicals and have the potential to reduce harm from cigarette smoke when used as tobacco cigarette substitutes. In this review, we examine the available clinical studies and population surveys on the respiratory health effects of ECs and HTPs in COPD patients.
  • As many COPD smokers prefer to smoke, conventional cigarette substitution should be considered as a valuable solution to the persistent problem of smoking, and combustion-free nicotine delivery technologies should be weight as a component of this strategy.
  • Our analysis of existing human studies on the respiratory health impact of ECs/HTPs substitution for COPD patients who smoke, fails to reach a clear conclusion because of the discordant findings and unreliable interpretations driven from surveys and clinical studies of modest quality.
  • This review article highlights the need for large, carefully designed, adequately controlled, long- term follow-up clinical trials to assess the true potential of combustion-free nicotine delivery technologies for sustained smoking cessation and reducing risk of harm from smoking, particularly among smokers with chronic obstructive pulmonary disease (COPD).

2020: COPD smokers who switched to e-cigarettes: health outcomes at 5-year follow up

  • Those in the EC user group achieved a marked decline in cigarette smoking or abstinence. COPD EC users had a significant diminution in COPD exacerbations; with the mean (±SD) exacerbation rate falling from 2.3 (±0.9) at baseline to 1.1 (±1.0) at 5 years (p < 0.001), whereas no significant changes were observed in the control group.
  • Patients were evaluated prospectively for their measurements of respiratory exacerbations, spirometric indices, quality of life using the COPD assessment tool (CAT), 6-min walk distance (6MWD), as well as conventional cigarette consumption.
  • Significant and constant improvements in lung function, CAT scores and 6MWD were reported in the EC user group over the 5-year observation period compared with the reference group (p < 0.05).

2021: Health outcomes in COPD smokers using heated tobacco products: a 3-year follow-up

2022: Electronic cigarettes as a harm reduction strategy among patients with COPD: protocol for an open-label two arm randomized controlled pilot trial

  • A harm reduction approach with the goal of achieving CC switching may be a more pragmatic approach, making EC use particularly appropriate with COPD [25]. EC represent a potentially effective harm reduction tool that is safer than smoking CC [18, 23, 24]. Smokers with COPD, however, tend to be older and may have a higher level of addiction to nicotine than the average smoker and the feasibility and preliminary effectiveness of an EC harm-reduction strategy in a COPD population has not been explored.
  • Our study protocol has a few limitations. First, as a pilot study the protocol is not powered to detect small differences in CPD or CAT Scores between the NRT and EC arms. Second, CAT Score is not the gold standard for the assessment of respiratory health.

External Links

Rise and Vape Podcast double issue on Asthma and COPD

Episode 1 Asthma


Episode 2 COPD