There has been limited evidence for the association between chronic obstructive pulmonary disease (COPD) and the incidence of lung cancer among never smokers. We aimed to estimate the risk of lung cancer incidence in never smokers with COPD, and to compare it with the risk associated with smoking. This cohort study involved 338 548 subjects, 40 to 84 years of age with no history of lung cancer at baseline, enrolled in the National Health Insurance Service National Sample Cohort. During 2 355 005 person-years of follow-up (median follow-up 7.0 years), 1834 participants developed lung cancer. Compared with never smokers without COPD, the fully-adjusted hazard ratios (95% CI) for lung cancer in never smokers with COPD, ever smokers without COPD, and ever smokers with COPD were 2.67 (2.09 to 3.40), 1.97 (1.75 to 2.21), and 6.19 (5.04 to 7.61), respectively. In this large national cohort study, COPD was also a strong independent risk factor for lung cancer incidence in never smokers, implying that COPD patients are at high risk of lung cancer, irrespective of smoking status.

中文翻译：

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从不吸烟者的慢性阻塞性肺疾病和肺癌发病率：一项队列研究

慢性阻塞性肺疾病 (COPD) 与从不吸烟者肺癌发病率之间存在关联的证据有限。我们旨在评估从不吸烟的 COPD 患者的肺癌发病风险，并将其与吸烟相关的风险进行比较。该队列研究涉及 338 548 名年龄在 40 至 84 岁之间且基线时没有肺癌病史的受试者，他们参加了国家健康保险服务国家样本队列。在 2 355 005 人年的随访期间（中位随访时间为 7.0 年），1834 名参与者患上了肺癌。与没有 COPD 的从不吸烟者相比，从不吸烟的 COPD、不吸烟的 COPD 和曾经吸烟的 COPD 患者的肺癌完全调整风险比（95% CI）分别为 2.67（2.09 至 3.40）、1.97（1.75 至 2.21 ）和 6.19（5.04 至 7.61），分别。在这项大型全国队列研究中，COPD 也是从不吸烟者肺癌发病率的一个强有力的独立危险因素，这意味着无论吸烟状况如何，COPD 患者都有患肺癌的高风险。