SUMMARY

Some get off to a bad start, others simply do not realize they have a disease. And others fall into the trap of thinking that tobacco exposure could be too low to cause harm. Either way, to identify and treat persons living with COPD early in their disease is intriguing- and possible.

Preterm birth and lifelong lung vulnerability

Preterm birth and the resulting disruption in lung development are well-recognized factors for early-onset COPD. However, as the lungs remain generally less complex structured, less vascularised, and with molecular and immunological differences compared to “normal” lungs, prematurely born may be predisposed for other diseases.¹

While it has been shown in Nordic registry data that the more preterm a person was born, the higher the risk for disease, it remains unclear to what extent therapeutic measures early in life contribute to the development of diseases. Traditionally, patients in studies have been stratified based on presence or absence of bronchopulmonary dysplasia, BPD, but in the end, this is a proxy, highly affected by indication bias. As the definition of BPD varies across countries and over time, longitudinal data may not reflect the current clinical definitions, complicating interpretation of data. Moreover, the studies conducted investigate survivors of neonatal critical care – but who is missing from this data and what does it mean for our understanding of disease burden? When Professor Stajonevic presented her thoughts, she called for more modern statistical methods and to “leave kitchen sink regressions” behind. It is clear though that small lungs are more vulnerable to environmental exposure throughout life and should be carefully cared for by individuals born preterm and their healthcare providers.

Finding the undiagnosed: Screening versus case finding

A significant proportion of individuals (believed to be up to 70%) are undiagnosed and still fulfil the criteria for a COPD diagnosis. Professor Shawn Aaron presented two ways to find these persons, being screening measures or case finding activities.^2,3 While screening would examine a proportion of the general population, case finding is a more targeted approach, e.g. by focusing on groups with higher risk, presence of symptoms or exposure. Persons could also fill in an online questionnaire and being provided the % probability of having a COPD or asthma diagnosis and with them, self-recruit themselves to proper medical investigation. With these methods, not only early or mild cases are found, but more than two thirds have sadly already progressed to a moderate and severe stage. Once identified, treatment according to latest guidelines showed better results than standard care in both COPD assessment tool, CAT, and St. George´s Respiratory Questionnaire.²

Tobacco Exposure: No Safe Threshold

Yunus Çolak reported data from the Copenhagen city heart study analysing tobacco exposure in relation to the risk of developing COPD.⁴ More than 20% of individuals with tobacco exposure below the threshold of 10 pack-years developed COPD. Clear reductions in total life expectancy of about 5 years were detected already with this low tobacco exposure. The risk does increase with increased tobacco exposure. The results were clear- there is no magic number of “pack-years” for low risk and good prognosis of COPD.

Reference

1. https://www.who.int/europe/news-room/fact-sheets/item/tobacco
2. Institute for Health Metrics and Evaluation (IHME). Global Burden of Disease 2021: Findings from the GBD 2021 Study. Seattle, WA: IHME, 2024.
3. Alari A, Ballester J, Milà C, et al. Quantifying the short-term mortality effects of wildfire smoke in Europe: a multicountry epidemiological study in 654 contiguous regions. Lancet Planet Health. 2025;9(8):101296. doi:10.1016/j.lanplh.2025.101296
4. https://civil-protection-humanitarian-aid.ec.europa.eu/what/civil-protection/wildfires_en  
5. Gupta, J., Liverman, D., Prodani, K. et al. Earth system justice needed to identify and live within Earth system boundaries. Nat Sustain 6, 630–638 (2023). https://doi.org/10.1038/s41893-023-01064-1
6. https://www.who.int/news-room/fact-sheets/detail/household-air-pollution-and-health
7. Caillaud D, Leynaert B, Keirsbulck M, Nadif R; mould ANSES working group. Indoor mould exposure, asthma and rhinitis: findings from systematic reviews and recent longitudinal studies. Eur Respir Rev. 2018;27(148):170137. Published 2018 May 15. doi:10.1183/16000617.0137-2017
8. Millett C, Lee JT, Laverty AA, Glantz SA, Majeed A. Hospital admissions for childhood asthma after smoke-free legislation in England. Pediatrics. 2013;131(2):e495-e501. doi:10.1542/peds.2012-2592
9. Mackay DF, Turner SW, Semple SE, Dick S, Pell JP. Associations between smoke-free vehicle legislation and childhood admissions to hospital for asthma in Scotland: an interrupted time-series analysis of whole-population data. Lancet Public Health. 2021;6(8):e579-e586. doi:10.1016/S2468-2667(21)00129-8