New research on the prevalence of chronic obstructive pulmonary disease in England

3 August 2023

New research by Imperial College London, in partnership with the Taskforce for Lung Health, estimates that 1.4 million people were living with a diagnosis of chronic obstructive pulmonary disease (COPD) in England in 2019. This is 27 per cent higher compared with using the same method as the quality and outcomes framework (QOF).

Researchers at Imperial College London worked to understand the true prevalence of COPD in people aged 40 and over in England and how this changed from 2000 to 2019. They compared this with estimates using the same method as the quality and outcomes framework (QOF), which is often referenced when talking about the prevalence of different conditions.

Prevalence of COPD is the proportion of people living with COPD at a specific time.

For people aged 40 and above, Imperial College estimated that the prevalence of diagnosed COPD in England in 2019 was 4.9%, meaning around 1.4 million people in England were living with a diagnosis of COPD.

In comparison, using the QOF method for prevalence instead, around 3.9% of people aged 40 and above were estimated to have a diagnosis of COPD, equating to a difference of almost 300,000 people.

Why prevalence is important

The primary method used by Imperial College London to estimate the prevalence of diagnosed COPD was to determine people with either a validated primary care diagnosis of COPD or an admission in secondary care with COPD (or emphysema) as the primary or secondary diagnosis. The researchers’ definition of a validated primary care diagnosis was broader with respect to the number of clinical codes used but more specific than those used within QOF. It should be noted that QOF only considers primary care while the researchers estimate includes secondary care as well.

If the true prevalence of COPD is underestimated, there is a risk COPD will not receive the investment and attention that it needs. NHS England, The Department of Health and Social Care (DHSC) and each integrated care system (ICS) must be aware of the true extent of COPD prevalence and ensure they can provide adequate treatment and care for those with the condition. More also needs to be done to address the core causes of COPD, such as providing local authorities with appropriate funding for smoking cessation services.

The extent of COPD across the country is highly variable. The map below shows the estimated differences in prevalence across regions in England in 2019, from 3.9% in London to 7.2% in the North East:

A Flourish map

Undiagnosed Prevalence

Imperial College also looked at people with a history of smoking, at least 1 of the respiratory symptoms, cough, dyspnoea, or sputum production, a prescription for an inhaler, and no diagnosis of asthma to determine who may be potentially undiagnosed with COPD.

Using this definition and looking at those without validated COPD, the undiagnosed prevalence of COPD could be as high as 1.9%. This could mean an additional 500,000 people living in England with COPD in addition to those diagnosed.  While these symptoms may be attributable to other conditions (meaning this figure may not represent only those with undiagnosed COPD), it still shows there could be many hundreds of thousands of people living with COPD without a diagnosis.

This diagnosis gap desperately needs addressing as people living with an undiagnosed condition cannot get the treatment and care they need, likely leading to worse health outcomes.

To tackle this, NHS England must act, encouraging primary care and the wider system to undertake targeted case finding to identify people who have symptoms of COPD who aren’t diagnosed, expand the targeted lung health check programme to incorporate spirometry, and reduce the gap between first onset of symptoms and diagnosis. As a Taskforce we have made huge strides in supporting the latter ambition by working with NHS England to create a new breathlessness pathway2, which aims to diagnose a person’s breathlessness symptoms within six months of presenting to their GP.

Finally, as prevalence estimates cannot capture people who may develop COPD but who do not seek care (and therefore have their symptoms recorded), NHS England must also encourage people to seek treatment in the first place. This will mean ensuring that people are aware of the key symptoms, such as breathlessness.

Access to care

The researchers also found that not everyone had access to the care they needed. Pulmonary rehabilitation (PR) is an effective treatment for people with COPD to improve their exercise capacity and reduce breathlessness. Referrals are based on how breathless someone is. This is measured on an MRC grade, and someone must score 3 or above to be referred to PR. By 2019, only 13.8% of people the researchers looked at had been referred to PR and only 4.3% had completed a course in 2019, which shows that this treatment is not being offered to everyone that could benefit from it.

Spirometry is a key part of diagnosing COPD, and an accurate recording of someone’s lung capacity is essential to track how well their COPD is being managed. A spirometry test can measure the forced expiratory volume (FEV) of a patient. This refers to the volume of breath a patient can exhale within a number of seconds compared with what volume would be predicted for that patient based on demographics such as height and age.

While recording of FEV has improved since 2000 to 2019, in 2019 almost 30% of patients still did not have a record of their FEV (within 1 second). FEV may be recorded as free text or scanned into a patient’s notes so we do not know if recording is quite as bad as this suggests, but this does mean a significant proportion of the COPD population may not be receiving spirometry or having those results reported.

The full paper is available here.

  1. The quality and outcomes framework (QOF) reports on all ages, the figure of 3.9% was calculated as the prevalence for those aged 40 and over based on QOF criteria.
  2. The breathlessness pathway is available on the NHS Futures page for those with a login here: Breathlessness diagnosis pathway – Respiratory Disease Programme – FutureNHS Collaboration Platform