The role of lung cancer risk and comorbidity in lung cancer screening use

Although lung cancer screening (LCS) with low dose computed tomography has been shown to reduce lung cancer mortality, benefits and harms of screening vary among eligible adults. The goal of this study was to evaluate whether LCS is more commonly used among populations most likely to benefit, namely adults with high lung cancer risk and low comorbidity. In this cohort study of patients eligible for LCS, we used data from the electronic health record to evaluate the relationship between lung cancer risk, comorbidity, and receipt of LCS. We also evaluated use of diagnostic chest CT. Analyses used a nonparametric test for trend across quartiles of lung cancer risk and comorbidity. The study sample included 551 LCS-eligible adults who were followed for a mean 2.9 years (SD 1.6 years). A cumulative 190 (34 %) received at least 1 LCS, and 141 (26 %) had a diagnostic chest CT. Receipt of LCS increased across quartiles of lung cancer risk (5 per 100 person years in the lowest quartile vs 13 per 100 person-years in the highest, p < 0.001 for test of trend). LCS receipt decreased across increasing quartiles of comorbidity (14 vs 8 per 100 person-years, p = 0.008). Diagnostic CT was more common in among patient with higher levels of comorbidity (15 vs 5 per 100 person-years, p < 0.001). In conclusion, lung cancer screening was more commonly used in patients with greater lung cancer risk and lower comorbidity. Results suggest that both patient characteristics and use of diagnostic imaging may shape current patterns of LCS use.