Frailty, comorbidity and survival comparisons between populations eligible for screening according to risk factor versus risk score criteria: results from the Yorkshire Lung Screening Trial

Background Lung cancer screening is effective for people at higher risk of the disease, but there is no international consensus on eligibility criteria. Some programmes use risk factors; others use multivariable risk scores, which might target an older, more comorbid population and thus limit life years gained. In this study, we compare frailty, comorbidities and overall survival between different eligible populations. Methods Participants aged 55–74 years undergoing lung cancer risk assessment in the Yorkshire Lung Screening Trial were analysed, comparing those who met the US Preventive Services Task Force 2021 lung cancer screening criteria (USPSTF 2021 ) criteria against established risk-based criteria currently used in screening protocols (Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial risk model (PLCO m2012 ) ≥1.51%, used internationally, and the Liverpool Lung Project risk model (version 2) (LLP v2 ) ≥2.5%, used in the UK), examining the number of individuals with frailty and comorbidities selected by each approach. In addition, risk score thresholds were set to select equivalent numbers of people screened compared with USPSTF 2021 . Data recorded in primary care prior to randomisation were retrospectively extracted to allow calculation of the electronic Frailty Index (eFI) and an overall comorbidity count. Frailty, comorbidity counts and 3-year overall survival were compared between these various populations. Results Of 11 994 individuals aged 55–74 undergoing risk assessment, 3502 were eligible by USPSTF 2021 , 3139 by PLCO m2012 ≥1.51% and 3957 by LLP v2 ≥2.5%. The proportion of individuals with moderate/severe frailty was lower for the USPSTF 2021 population (10.6%) compared with PLCO m2012 ≥1.51% (13.1%, adjusted p=0.0777) and LLP v2 ≥2.5% (13.4%, adjusted p=0.0272). The USPSTF 2021 identified significantly fewer individuals with multiple comorbidities (30.8%) than the PLCO m2012 (36.1%, adjusted p=0.0033) and the LLP v2 (37.3%, adjusted p=0.0001). When compared in equivalent populations, both PLCO m2012 with a threshold of 1.32%, and LLP v2 with a threshold of 2.92%, had a higher proportion of people both with moderate/severe frailty (12.6%, adjusted p=0.221 and 14.0%, adjusted p=0.0067 respectively) and multiple comorbidities (35.1%, adjusted p=0.0211 and 38.5%, adjusted p