Center for Thoracic Surgery, Department of Surgical Sciences, University of Insubria, Varese, Italy.
J Thorac Oncol. 2010 Apr;5(4):428-35. doi: 10.1097/JTO.0b013e3181d2efc7.
We hypothesize that mortality risk profile of participants and nonparticipants in nonrandomized lung cancer (LC) screening of smokers may be different.
In 1997, a population-based cohort of 5815 smokers of Varese Province was invited to nonrandomized LC screening by annual chest x-ray examination for 4 years. LC risk factors and screening participation rate were recorded. Except for screening, the whole cohort received usual care. After 9.5-year observation, we compared mortality of participants versus nonparticipants by assessing age-standardized all-cause mortality rate ratio (MRR) and disease group-specific MRR with 95% confidence intervals (95% CI).
Self-selected screening participants were 21% of cohort. Participants were younger (p < 0.001), were more frequently current smokers (p = 0.019), had more pack-years of smoking (p < 0.0001), and had higher rate of LC family history (p < 0.0001) and of occupational LC risk (p < 0.0001) relative to nonparticipants. In logistic regression analysis familial LC, occupational risk and pack-years smoked were significant predictors of participation in screening and of developing LC. Participants displayed a healthy effect, as shown by all-cause MRR = 0.67 (95% CI, 0.53-0.84), all cancers except LC MRR = 0.61 (95% CI, 0.41-0.91), cardiovascular diseases MRR = 0.38 (95% CI, 0.22-0.63), and noncancer disease other than cardiovascular or respiratory MRR = 0.57 (95% CI, 0.34-0.92). The LC mortality (MRR = 1.40; 95% CI, 1.03-1.91) was higher in participants relative to nonparticipants (p = 0.031).
The selection effect in LC screening participants was dual: healthy effect and higher LC mortality. In assessing the overall effectiveness of LC screening on a population level, a higher LC mortality risk in participants should be considered.
我们假设，在非随机肺癌（LC）筛查中，参与者和非参与者的死亡率风险特征可能不同。
1997 年，对瓦雷泽省的一个基于人群的 5815 名吸烟者队列进行了邀请，参加为期 4 年的年度胸部 X 射线检查的非随机 LC 筛查。记录了 LC 的危险因素和筛查参与率。除了筛查之外，整个队列都接受了常规护理。经过 9.5 年的观察，我们通过评估年龄标准化全因死亡率比值（MRR）和疾病组特异性 MRR 及其 95%置信区间（95%CI），比较了参与者与非参与者的死亡率。
自我选择参加筛查的参与者占队列的 21%。与非参与者相比，参与者更年轻（p < 0.001），更频繁地吸烟（p = 0.019），吸烟量更大（p < 0.0001），并且具有更高的 LC 家族史（p < 0.0001）和职业性 LC 风险（p < 0.0001）。在逻辑回归分析中，LC 家族史、职业风险和吸烟量是参与筛查和发生 LC 的显著预测因素。参与者表现出健康效应，全因死亡率 MRR = 0.67（95%CI，0.53-0.84），除 LC 外的所有癌症 MRR = 0.61（95%CI，0.41-0.91），心血管疾病 MRR = 0.38（95%CI，0.22-0.63），非心血管或呼吸系统疾病 MRR = 0.57（95%CI，0.34-0.92）。与非参与者相比，参与者的 LC 死亡率（MRR = 1.40；95%CI，1.03-1.91）更高（p = 0.031）。
LC 筛查参与者的选择效应是双重的：健康效应和更高的 LC 死亡率。在评估人群水平上 LC 筛查的总体效果时，应该考虑参与者的更高 LC 死亡率风险。
