New study reveals trends in lung disease across the UK over two decades

The findings emphasise shifting trends in disease incidence and prevalence, as well as the impact of the COVID-19 pandemic on respiratory health across the UK.

Researchers from the Inflammation and Immunity Driver Programme analysed data from national health records between 2004 and 2023, and found that the incidence of asthma and COPD has decreased over time. In contrast, cases of ILD—a group of conditions that cause lung scarring—have increased across all four nations.

In England, the rate of new asthma cases in 2019 was 11% lower than in 2005. The decline was even steeper in Wales (34%), Scotland (33%), and Northern Ireland (16%). Similarly, COPD incidence dropped by 17% in England and 33% in Wales. However, ILD cases rose sharply, with rates more than tripling in England and Northern Ireland over the same period.

Despite falling incidence rates, asthma remains highly prevalent, affecting nearly one in six people in Wales (16.4%), one in seven in Scotland (13.2%), and almost one in ten in England (9.6%) and Northern Ireland (7.6%). COPD affects between 3% and 6% of the population, while ILD, though less common, still impacts thousands across the UK.

The study revealed a substantial gap in lung disease diagnoses during the COVID-19 pandemic. By analysing expected versus actual diagnosis rates, the team estimated that new cases of asthma and COPD were diagnosed at only a third of the anticipated levels, while ILD diagnoses were nearly halved. These findings indicate that a significant number of individuals with respiratory conditions may have remained undetected and without necessary treatment.

The researchers employed a harmonised approach to analysing electronic health records across the UK, ensuring comparable data between the four nations. This approach sets the study apart from previous studies, which have focused on individual countries using differing methods, making it difficult to compare trends.

Given the widespread burden of respiratory diseases and the lingering effects of the pandemic, the study highlights the ongoing importance of effective diagnosis and management strategies throughout the UK.

Dr Hannah Whittaker, an Inflammation and Immunity Research Fellow based at Imperial College London said: “We hope that these methods and national level estimates can be used to inform public health planning.”

The study was supported by Health Data Research UK as part of the Inflammation and Immunity Driver Programme.

Click here to read the full paper: https://thorax.bmj.com/content/early/2025/04/08/thorax-2024-222699 

Full citation: Whittaker H, Kramer Fiala Machado A, Hatam S, et al. Incidence and prevalence of asthma, chronic obstructive pulmonary disease and interstitial lung disease between 2004 and 2023: harmonised analyses of longitudinal cohorts across England, Wales, South-East Scotland and Northern Ireland. Thorax. Published Online First: 08 April 2025. Doi: 10.1136/thorax-2024-222699