ABSTRACT
Introduction
In May 2022, the US Preventive Services Task Force published their recommendation against screening for chronic obstructive pulmonary disease (COPD) in asymptomatic adults. However, we argue the routine use of spirometry in both asymptomatic and symptomatic high-risk smokers has utility.
Areas covered
We provide published and unpublished observations from a secondary analyses of the American College of Radiology Imaging Network (ACRIN), arm of the National Lung Screening Trial, including 18,463 high-risk current or former smokers who underwent pre-bronchodilator spirometry at baseline. According to history alone, 20% reported a prior diagnosis of ‘COPD,’ although only 11% (about one half), actually had airflow limitation (Diagnosed COPD) and 9% had Global Initiative for Obstructive Pulmonary Disease GOLD 0 Pre-COPD. Of the remaining 80% of ‘asymptomatic’ screening participants, 23% had airflow limitation (Screen-detected COPD) and 13% had preserved ratio impaired spirometry (PRISm). This means 45% of this high-risk cohort were reclassified by spirometry, and together with comorbid disease, identified subgroups where lung cancer screening efficacy could be optimized by between 2–6 fold.
Expert opinion
Our preliminary findings suggest lung cancer screening outcomes vary according to ‘new’ COPD-related spirometric-defined subgroups and that screening spirometry, together with comorbid disease, identifies those for whom lung cancer screening is mostly beneficial or potentially harmful.
Article highlights
Screening spirometry helps to correctly classify nearly 50% of older high risk current or former smokers, into those with COPD (airflow limitation) and Pre-COPD (PRISm and GOLD 0).
Screening spirometry helps define these subgroups of high-risk smokers who experience a 2-fold or more increased cardiovascular and lung cancer-related mortality and for whom beneficial evidence-based interventions exist. By utilizing a screening spirometry approach to identify those with these COPD-related treatable traits and provide these mortality-reducing interventions, decades of under-diagnosis and under-treatment of patients with COPD may begin to be addressed.
Lung cancer screening is a complex, resource intensive and costly intervention, that effectively reduces lung cancer mortality for many but not all high-risk smokers. Lung cancer screening efficacy varies by 2-6-fold according to the presence of respiratory comorbidity and possibly diabetes mellitus, and for some confers no clear benefit (i.e. reducing lung cancer mortality).
If lung cancer screening is to achieve its full potential to reduce deaths from lung cancer, and in doing so avoid harm to those for whom lung cancer screening contributes to greater morbidity and mortality, then utilizing screening spirometry would appear prudent.
Screening spirometry identifies those with Undiagnosed COPD (asymptomatic airflow limitation) and those with GOLD 0 pre-COPD, where the lung cancer screening efficacy was 3-fold less effective in the latter.
Future studies are urgently needed to confirm findings from the NLST which has revealed co-existing respiratory comorbid disease, defined in part by routine spirometry, which defines poor responders undergoing lung cancer screening that substantially attenuates the primary aim of lung cancer screening, to reduce lung cancer mortality.
Declaration of interest
The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants, or patents received or pending, or royalties.
Reviewer disclosures
Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.