Department of Thoracic surgery, First Hospital of China Medical University, Shenyang, Liaoning Province, China.
Department of Breast Surgery, First Hospital of China Medical University, Shenyang, Liaoning Province, China.
BMC Cancer. 2019 Apr 24;19(1):377. doi: 10.1186/s12885-019-5601-9.
Smoking is one of the well-established risk factors for gastric cancer incidence, yet whether men are more or equally susceptible to gastric cancer due to smoking compared with women is a matter of controversy. The aim of this study was to investigate and compare the effect of sex on gastric cancer risk associated with smoking.
We conducted a systemic literature search in MEDLINE, EMBASE, and the Cochrane CENTRAL databases to identify studies published from inception to December 2018. We included prospective observational studies which reported effect estimates with 95% confidence intervals (CIs) for associations of current or former smokers with the incidence of gastric cancer by sex. We calculated the ratio of relative risk (RRR) with corresponding 95% CI based on sex-specific effect estimates for current or former smokers versus non-smokers on the risk of gastric cancer.
We included 10 prospective studies with 3,381,345 participants in our analysis. Overall, the summary RRR (male to female) for gastric cancer risk in current smokers was significantly increased compared with non-smokers (RRR: 1.30; 95% CI: 1.05-1.63; P = 0.019). Furthermore, there was no significant sex difference for the association between former smokers and gastric cancer risk (RRR: 1.20; 95% CI: 0.92-1.55; P = 0.178). However, the result of sensitivity analysis indicated the pooled result was not stable, which was altered by excluding a nested case-control study (RRR: 1.31; 95% CI: 1.10-1.57; P = 0.002).
This systematic review showed a potential sex difference association between current smokers and the risk of gastric cancer. The sex differential in smokers can give important clues for the etiology of gastric cancers and should be examined in further studies.
吸烟是胃癌发病的既定危险因素之一，但与女性相比，男性因吸烟而患胃癌的易感性是否更高或相等，这是一个有争议的问题。本研究旨在调查和比较性别对与吸烟相关的胃癌风险的影响。
我们在 MEDLINE、EMBASE 和 Cochrane CENTRAL 数据库中进行了系统的文献检索，以确定从开始到 2018 年 12 月发表的研究。我们纳入了前瞻性观察性研究，这些研究报告了按性别划分的当前或既往吸烟者与胃癌发病率之间关联的效应估计值及其 95%置信区间（CI）。我们根据当前或既往吸烟者与非吸烟者相比发生胃癌的风险，计算了相对风险比（RRR）及其相应的 95%CI。
我们的分析纳入了 10 项前瞻性研究，共 3381345 名参与者。总体而言，与非吸烟者相比，当前吸烟者患胃癌的风险汇总 RRR（男性对女性）显著增加（RRR：1.30；95%CI：1.05-1.63；P=0.019）。此外，既往吸烟者与胃癌风险之间的关联没有显著的性别差异（RRR：1.20；95%CI：0.92-1.55；P=0.178）。然而，敏感性分析的结果表明，汇总结果不稳定，排除一项巢式病例对照研究后结果发生了变化（RRR：1.31；95%CI：1.10-1.57；P=0.002）。
本系统评价显示，当前吸烟者与胃癌风险之间存在潜在的性别差异关联。吸烟人群中的性别差异可为胃癌的病因学提供重要线索，应在进一步的研究中进行检验。
