After careful consideration, the American Thoracic Society canceled its annual meeting that was to take place in Philadelphia, Pennsylvania from May 15-20, because of the ongoing coronavirus disease 2019 (COVID-19) pandemic. Although the live events will not proceed as planned, our readers can still find coverage of research that was scheduled to be presented at the meeting. A virtual event is being planned for later this year.
Patients with asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) may have an increased independent risk for lung cancer that is similar to those with COPD, but higher than smokers with asthma and normal spirometry values.
Researchers conducted in a group of individuals with ≥30 pack-years of smoking from the American College of Radiology Imaging Network (ACRIN) subcohort of the large, randomized National Lung Cancer Screening Trial (NSLT) who had undergone baseline pulmonary function testing. Results of the analysis were scheduled to be presented at the American Thoracic Society (ATS) International Conference. (Select research will be available in a virtual format later this year.)
Investigators sought to compare lung cancer risk in patients with ACO vs those with COPD and other disorders that are associated with airway obstruction. A total of 13,911 patients were evaluated. The NSLT participants were divided into 5 groups: (1) smokers with no airway obstruction (n=6447); (2) those with Preserved Ratio Impaired Spirometry (PRISm, ratio of forced expiratory volume in 1 second [FEV1] over forced vital capacity [FVC] ≥0.7 and FEV1 <80% predicted; n=2547); (3) persons with a history of childhood asthma (n=281); (4) individuals with COPD (ie, FEV1/FVC <0.7; n=4428); and (5) those with ACO (ie, childhood asthma and FEV1/FVC <0.7; n=208).
The incidence rate of lung cancer per 1000 person-years was 13.2 (95% CI, 8.1-21.5); 11.7 (95% CI, 10.5-13.1); 1.8 (95% CI, 0.6-5.4); 7.7 (95% CI, 6.4-9.2); and 4.1 (95% CI, 3.5-4.8) in patients with ACO, those with COPD, asthmatic smokers, PRISm patients, and smokers with normal spirometry readings, respectively. Patients with ACO had an increased risk for lung cancer compared with asthmatic smokers (incidence rate ratio [IRR], 4.5; 95% CI, 1.3-16.0) and smokers with normal spirometry values (IRR, 2.4; 95% CI, 1.3-4.3). Additionally, individuals with ACO exhibited a lung cancer risk that was similar to that in patients with COPD (IRR, 1.11; 95% CI, 0.62-1.97) and in PRISm patients (IRR, 1.51; 95% CI, 0.83-2.75).
The investigators concluded that the results of this study imply that ACO is an independent risk factor for the development of lung cancer that warrants consideration when making decisions regarding screening for lung cancer.
Charokopos A, Braman SS, Whittaker Brown SA, et al. Lung cancer risk of patients with asthma-chronic obstructive pulmonary disease overlap. Am J Respir Crit Care Med. 2020;201:A6462.