Department of Epidemiology and Biostatistics, Imperial College London, London, UK.
Ann Oncol. 2012 Apr;23(4):843-52. doi: 10.1093/annonc/mdr398. Epub 2011 Sep 2.
Questions remain about the shape of the dose-response relationship between body mass index (BMI) and pancreatic cancer risk, possible confounding by smoking, and differences by gender or geographic location. Whether abdominal obesity increases risk is unclear.
We conducted a systematic review and meta-analysis of prospective studies of the association between BMI, abdominal fatness and pancreatic cancer risk and searched PubMed and several other databases up to January 2011. Summary relative risks (RRs) were calculated using a random-effects model.
Twenty-three prospective studies of BMI and pancreatic cancer risk with 9504 cases were included. The summary RR for a 5-unit increment was 1.10 [95% confidence interval (CI) 1.07-1.14, I(2) = 19%] and results were similar when stratified by gender and geographic location. There was evidence of a non-linear association, P(non-linearity) = 0.005; however, among nonsmokers, there was increased risk even within the 'normal' BMI range. The summary RR for a 10-cm increase in waist circumference was 1.11 (95% CI 1.05-1.18, I(2) = 0%) and for a 0.1-unit increment in waist-to-hip ratio was 1.19 (95% CI 1.09-1.31, I(2) = 11%).
Both general and abdominal fatness increases pancreatic cancer risk. Among nonsmokers, risk increases even among persons within the normal BMI range.
目前仍存在一些问题，如 BMI（身体质量指数）与胰腺癌风险之间的剂量-反应关系的形状、可能存在的吸烟混杂因素以及性别或地理位置差异等。腹部肥胖是否会增加风险也不明确。
我们对 BMI、腹部肥胖与胰腺癌风险之间关联的前瞻性研究进行了系统性回顾和荟萃分析，并检索了 PubMed 及其他几个数据库，检索截至 2011 年 1 月。采用随机效应模型计算汇总相对风险（RR）。
共纳入了 23 项 BMI 与胰腺癌风险的前瞻性研究，包含 9504 例病例。5 个单位 BMI 增加的汇总 RR 为 1.10（95%置信区间为 1.07-1.14，I(2) = 19%），按性别和地理位置分层后结果相似。存在非线性关联的证据（P(non-linearity) = 0.005）；然而，在不吸烟者中，即使在“正常”BMI 范围内也存在更高的风险。腰围增加 10cm 的汇总 RR 为 1.11（95%置信区间为 1.05-1.18，I(2) = 0%），腰围与臀围比值增加 0.1 单位的 RR 为 1.19（95%置信区间为 1.09-1.31，I(2) = 11%）。
总体和腹部肥胖都会增加胰腺癌风险。在不吸烟者中，即使在正常 BMI 范围内，风险也会增加。
