143MO Risk of lung cancer among current smokers by pack-year smoking: A cohort study with 23 years of follow-up

We have recently demonstrated that current heavy smokers with >20 pack-year (PY) smoking history (median, 48.8, IQR, 31.6–57.0 PY) and non-heavy (<20 PY; median, 11.4; 7.3–14.4 about 40- 10-times higher risk of lung cancer, respectively (JAMA-Oncol. 2022; 8:1428–1437). In the study, we examined magnitude graded increase associated PY among smokers. Of 2505 community-dwelling older (mean age, 73 ± 5.7 years, 69% women, 17% African American) in Cardiovascular Health Study (CHS), 1973 were never-smokers. The 532 categorized based on into: <20 (n = 95), 20–39 157), 40–59 181) ≥60 94). Cause-specific HR (95% CI) for incident during 23 years follow-up estimated 4 groups (reference: never-smokers) Cox regression model, adjusting sex, race competing death. Incident cancer occurred 0.5% never smokers, 5.0%, 14.6%, 17.7% 16.0% those <20, 20–39, 40–59, history, respectively. Compared cause-specific HRs CIs) 9.73 (3.27–28.99), 30.33 (14.25–64.53), 42.97 (20.76–88.94), 46.02 (20.08–105.48), whom low-dose computed tomography screening is not recommended high, but was 3 times PY, plateaued PY. This study underscores importance abstinence early cessation.