Abstract Introduction Chronic Obstructive Pulmonary Disease (COPD) is a major comorbidity lung cancer screening cohort. The Lung Health Check (LHC) is Ireland’s first pilot of targeted lung cancer screening. A sub-aim of this pilot is to assess the prevalence and severity of airflow obstruction and emphysema in an Irish lung cancer screening cohort. Methods The LHC is a prospective study focused on community-based lung cancer screening. Adults aged 55-74 who are current or former smokers and deemed high risk based on risk prediction models were identified in primary care. Eligible individuals were invited to attend a mobile unit for respiratory assessment, smoking cessation, spirometry, low dose CT and optional biospecimen collection (blood, breath and sputum). Airflow obstruction was defined as per the GOLD criteria with an FEV1/FVC ratio 0.7. Results Thus far 8921 individuals have been invited while 6690 completed eligibility screening and 1494 were deemed eligible. To date, a total of 1076 participants underwent spirometry. The median age of attendees was 67 (IQR: 63-71) and 60% were male. Amongst those 395 (35%) were current smokers with a median 35 pack year history (IQR: 22-49) while 159 participants (40%) consented to smoking cessation. Overall median (IQR) FEV1 was 101 (86-115), FVC was 108 (95-124) and FEV1/FVC was 0.76 (0.7-0.8) (Figure 1A). Prior to testing, 152 (14%) of individuals self-reported a diagnosis of COPD. However, airflow obstruction, was evident in 251 (23.3%) of individuals meaning there were 183 new diagnoses of COPD (See Figure 1B). Among those with airflow obstruction, the median (IQR) FEV1 was 82% (66-97) and 236 (94%) were classified as GOLD I or II COPD. Of the 251 attendees with airflow obstruction, 118 (47%) were current smokers, 51 (43%) of these individuals consented to smoking cessation. Furthermore 34 (3.2%) of the total cohort had self-reported emphysema while, by LDCT 534 participants (46.9%) had radiological evidence of emphysema (See Figure 1C). Conclusions Our study reveals a high prevalence of previously undiagnosed airflow obstruction and emphysema within an Irish lung cancer screening population. The importance of identifying COPD in a screening cohort has been emphasised by previous trial data demonstrating that smokers with airflow obstruction have a greater incidence and mortality from lung cancer. The high prevalence of undiagnosed COPD carries significant implications for the accuracy of risk prediction models that depend on self-reported COPD status as an indicator of lung cancer risk . This abstract is funded by: the EU4Health (SOLACE consortium) and the Irish Cancer Society
Cronin et al. (Fri,) studied this question.