1 Division of Pulmonary, Critical Care and Sleep Medicine.
2 Health Equity and Rural Outreach Innovation Center, Ralph H. Johnson Veterans Affairs Hospital, Charleston, South Carolina.
Am J Respir Crit Care Med. 2016 Mar 1;193(5):534-41. doi: 10.1164/rccm.201507-1420OC.
Smoking is the largest contributor to lung cancer risk, and those who continue to smoke after diagnosis have a worse survival. Screening for lung cancer with low-dose computed tomography (LDCT) reduces mortality in high-risk individuals. Smoking cessation is an essential component of a high-quality screening program.
To quantify the effects of smoking history and abstinence on mortality in high-risk individuals who participated in the NLST (National Lung Screening Trial).
This is a secondary analysis of a randomized controlled trial (NLST).
Measurements included self-reported demographics, medical and smoking history, and lung cancer-specific and all-cause mortality. Cox regression was used to study the association of mortality with smoking status and pack-years. Kaplan-Meier survival curves were examined for differences in survival based on trial arm and smoking status. Current smokers had an increased lung cancer-specific (hazard ratio [HR], 2.14-2.29) and all-cause mortality (HR, 1.79-1.85) compared with former smokers irrespective of screening arm. Former smokers in the control arm abstinent for 7 years had a 20% mortality reduction comparable with the benefit reported with LDCT screening in the NLST. The maximum benefit was seen with the combination of smoking abstinence at 15 years and LDCT screening, which resulted in a 38% reduction in lung cancer-specific mortality (HR, 0.62; 95% confidence interval, 0.51-0.76).
Seven years of smoking abstinence reduced lung cancer-specific mortality at a magnitude comparable with LDCT screening. This reduction was greater when abstinence was combined with screening, highlighting the importance of smoking cessation efforts in screening programs.
吸烟是导致肺癌风险的最大因素，而那些在诊断后继续吸烟的人预后更差。使用低剂量计算机断层扫描（LDCT）筛查肺癌可降低高危人群的死亡率。戒烟是高质量筛查计划的重要组成部分。
定量评估在 NLST（国家肺癌筛查试验）中参与的高危人群的吸烟史和戒烟对死亡率的影响。
这是一项随机对照试验（NLST）的二次分析。
测量包括自我报告的人口统计学、医学和吸烟史以及肺癌特异性和全因死亡率。Cox 回归用于研究死亡率与吸烟状态和吸烟包年数的关系。通过 Kaplan-Meier 生存曲线检查基于试验臂和吸烟状态的生存差异。与以前的吸烟者相比，目前吸烟者的肺癌特异性（风险比 [HR]，2.14-2.29）和全因死亡率（HR，1.79-1.85）均增加，而不论筛查臂如何。在对照组中戒烟 7 年的前吸烟者的死亡率降低了 20%，与 NLST 中 LDCT 筛查报告的获益相当。吸烟戒断 15 年并结合 LDCT 筛查的获益最大，可使肺癌特异性死亡率降低 38%（HR，0.62；95%置信区间，0.51-0.76）。
7 年的戒烟可使肺癌特异性死亡率降低，其程度与 LDCT 筛查相当。当戒烟与筛查相结合时，这种降低更为显著，突出了戒烟努力在筛查计划中的重要性。
