Department of Research, Cancer Registry of Norway, N-0304 Oslo, Norway.
Nykøbing Falster Hospital, University of Copenhagen, DK-4800 Nykøbing Falster, Denmark.
Int J Environ Res Public Health. 2018 Dec 6;15(12):2760. doi: 10.3390/ijerph15122760.
: Alcohol and tobacco strongly increases the risk of cancers of the tongue, mouth, pharynx, larynx, and oesophagus, and are also established risk factors for cancer of the liver, colon, and rectum. It is well documented that these habits are unequally distributed among occupational groups. Most occupational cohort studies lack information on these potentially important confounders, and may therefore be prone to bias. : The aim of the study is to present Nordic standardized incidence ratios (SIRs) for alcohol and tobacco related cancer by occupation, after adjustment for alcohol and tobacco, and to compare to the unadjusted SIRs. : The study is based on the Nordic Occupational Cancer (NOCCA) database. We used confirmatory factor analysis models for simultaneous analysis of the cancer sites related to alcohol and tobacco, to obtain factors that allow for computation of adjusted expected numbers from the reference rates. We then calculated adjusted SIRs for the relevant cancer sites for each occupation. : For some occupations and cancers, the changes of risk estimates were striking, from significantly high to significantly low and vice versa. Among Nordic farmers, unadjusted SIRs for cancer of the mouth and oesophagus were 0.56 (95% confidence interval (CI) 0.51⁻0.61) and 0.67 (CI 0.63⁻0.70), respectively. After adjustment, estimates changed to 1.10 (CI 1.01⁻1.21) and 1.16 (CI 1.10⁻1.22). Unadjusted SIR for pharynx cancer among wood workers was 0.83 (CI 0.75⁻0.91), adjusted SIR was 1.14 (CI 1.03⁻1.25). For larynx cancer, results in the opposite direction were seen: unadjusted SIR for economically inactive was 1.38 (CI 1.31⁻1.46) while the adjusted SIR was 0.91 (CI 0.86⁻0.96). : Adjustment for the latent indicators of alcohol and tobacco consumption changed risk estimates for several occupations, gave a less confounded description of risk, and may guide in the identification of true risk factors.
酒精和烟草会大大增加舌、口腔、咽、喉和食管癌症的风险，也是肝癌、结肠癌和直肠癌的既定风险因素。有充分的证据表明，这些习惯在职业群体中分布不均。大多数职业队列研究缺乏这些潜在重要混杂因素的信息，因此可能容易产生偏差。
本研究的目的是按职业呈现与酒精和烟草相关的癌症的北欧标准化发病率比（SIR），在调整酒精和烟草因素后，并与未调整的 SIR 进行比较。
本研究基于北欧职业癌症（NOCCA）数据库。我们使用验证性因子分析模型对与酒精和烟草相关的癌症部位进行同时分析，以获得允许从参考率计算调整后预期数量的因素。然后，我们为每个职业计算了相关癌症部位的调整后 SIR。
对于某些职业和癌症，风险估计值的变化非常显著，从明显高到明显低，反之亦然。在北欧农民中，口腔和食管癌症的未调整 SIR 分别为 0.56（95%置信区间（CI）0.51⁻0.61）和 0.67（CI 0.63⁻0.70）。调整后，估计值分别变为 1.10（CI 1.01⁻1.21）和 1.16（CI 1.10⁻1.22）。木材工人中咽癌的未调整 SIR 为 0.83（CI 0.75⁻0.91），调整后的 SIR 为 1.14（CI 1.03⁻1.25）。相反，喉癌的结果则相反：经济不活跃者的未调整 SIR 为 1.38（CI 1.31⁻1.46），而调整后的 SIR 为 0.91（CI 0.86⁻0.96）。
调整酒精和烟草消费的潜在指标改变了几个职业的风险估计值，对风险进行了更具混杂因素的描述，并可能有助于确定真正的风险因素。
