Q&A: Why 70% of COPD Goes Undiagnosed, With Alvar Agustí, MD

Population analyses throughout North and South America, Europe, Australia, and Asia suggest only 20% to 30% of adult patients with persistent airflow limitation on spirometry carry a chronic obstructive pulmonary disease (COPD) diagnosis, leaving roughly 70% of cases worldwide unrecognized.¹ The error runs in both directions. Between 30% and 60% of patients with a prior physician diagnosis of COPD have no airflow obstruction when tested.¹

An analysis of national and international surveys covering 30,874 adults found 81.4% of spirometry-defined COPD cases were undiagnosed, and only 26.4% of participants reported a previous lung function test.² Underdiagnosis was more likely among men, younger adults, never and current smokers, and individuals with no prior spirometry or less severe airflow limitation.² Rates of undiagnosed disease ranged from 50.0% in Lexington, Kentucky, to 98.3% in Ile-Ife, Nigeria.²

Each gap carries a treatment consequence. Undiagnosed patients go untreated, while overdiagnosed patients receive inhaled therapies for a disease absent on spirometry.¹ GOLD continues to position spirometry as the diagnostic standard in the appropriate clinical context and recognizes pre-COPD as a category for individuals with respiratory symptoms or structural lung abnormalities without obstruction.³

Primary care sits at the center of the problem. Barriers include limited spirometry access, time pressure, and reliance on clinical judgment alone, which allows both missed and incorrect diagnoses to accumulate.¹

Alvar Agustí, MD, PhD, professor of medicine at the University of Barcelona and chair of the GOLD Board of Directors, brings a guideline perspective to these questions. Agustí sat down with the HCPLive team at the 2026 GOLD International COPD Conference in Philadelphia to discuss the scale of underdiagnosis, barriers to spirometry, pre-COPD, and earlier detection in primary care:

HCPLive: How large is the COPD underdiagnosis gap today, and which patients are most likely to slip through the cracks?

Alvar Agustí, MD, PhD: That's a very important question. In my opinion, and as I will present in my talk [UNCLEAR — please review], this is what I call a black hole. Data show about 70% to 80% of all patients with COPD in the world are not diagnosed. That means they are not treated. But also, of those diagnosed with COPD clinically, about 40% don't have COPD when you do spirometry, which means they are receiving the wrong treatment. And finally, when we do diagnose COPD correctly, we are almost always late, at the age of 60, 65, 70. That's too late…So that's a huge issue. No diagnosis, wrong diagnosis, late diagnosis is the very first issue.

HCPLive: Spirometry remains the diagnostic cornerstone but is underused in primary care. What is holding it back, and what might change?

Alvar Agustí, MD, PhD: You're right. So far, spirometry is still the key diagnostic criterion of COPD in the appropriate clinical context, which is something that is sometimes forgotten. But spirometry, which is noninvasive and relatively easy to do, is very often not done. Why? Well, there are several causes. There are patient-related causes. They really don't believe this is important. They don't want to do it. They know they will be asked to stop smoking, and they don't want to stop smoking.

There are healthcare system–related causes. Access to spirometry is not always there. Spirometry requires time, and time is not always there. And there are also physician-related factors. Physicians do not really value the importance of COPD, the impact of COPD, and they say, "Well, I know what COPD is. I don't need to test for it"…And [studies] show when they say so, they are wrong 50% of the time.

HCPLive: How should clinicians approach people with symptoms or structural lung changes who don't yet meet spirometric criteria for COPD?

Alvar Agustí, MD, PhD: That is what is called pre-COPD. In this new GOLD 2027 edition, we spent a lot of time clarifying the term, because many people think pre-COPD means you will eventually get COPD, so get obstruction, the O of COPD, and this is not always correct. There are patients who have emphysema…and symptoms, but no obstruction.

They are at risk of developing obstruction, but not all of them will. But honestly, this doesn't matter because individuals with symptoms or who have emphysema are already patients. They might not have obstructions. They might develop obstruction [UNCLEAR — please review], but they need treatment and care. And the problem is we do not have much evidence on the best treatment for pre-COPD patients.

HCPLive: If you could change one thing about how primary care finds COPD earlier, what would it be?

Alvar Agustí, MD, PhD: Spirometry. In the future, there will be other options. There is research going on into [certain] biomarkers…You can use an iPhone, and in theory, AI can help you diagnose COPD. This is not here yet. It may be in the future. Maybe other techniques, such as forced oscillometry, maybe other biomarkers. But today, spirometry, and an open mind [is key]…COPD can occur in young people, it can occur in women, it can occur in non-smokers. So the old paradigm, that this is a self-inflicted disease caused by smoking in old males, is correct, but only partially right. Now we know there is more to it.

Editor's Note: This transcript summary has been edited for grammar and clarity using artificial intelligence tools.

References

1. Diab N, Gershon AS, Sin DD, et al. Underdiagnosis and overdiagnosis of chronic obstructive pulmonary disease. Am J Respir Crit Care Med. 2018;198(9):1130-1139. doi:10.1164/rccm.201804-0621CI.

2. Lamprecht B, Soriano JB, Studnicka M, et al. Determinants of underdiagnosis of COPD in national and international surveys. Chest. 2015;148(4):971-985. doi:10.1378/chest.14-2535.

3. Global Initiative for Chronic Obstructive Lung Disease. Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease: 2026 Report. Accessed November 5, 2026. https://goldcopd.org.