Cancer Epidemiology Centre, Cancer Council Victoria, Carlton, Victoria, Australia.
Cancer Epidemiol Biomarkers Prev. 2010 Nov;19(11):2978-86. doi: 10.1158/1055-9965.EPI-10-0543. Epub 2010 Sep 24.
Epidemiologic studies have consistently reported positive associations between obesity and colon cancer risk for men, but the evidence is less consistent for women. Few studies have investigated effects of weight change on colon cancer risk.
Using the Melbourne Collaborative Cohort Study, which recruited men and women mostly in 40 to 69 years of age, we investigated associations between weight and body mass index (BMI) at age 18 years and at study entry and weight change since age 18 years and colon cancer. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox regression.
During follow-up of 16,188 men and 23,438 women for 14 years on average, we ascertained 569 incident colon cancers. Weight and BMI at study entry were positively associated with colon cancer risk for men [HR, 1.12 (95% CI, 1.04-1.21) per 5-kg increment; HR, 1.39 (95% CI, 1.12-1.71) per 5 kg/m(2)], but not women. Risk of colon cancer was not associated with weight or BMI at age 18 years. Adult weight change was positively associated with colon cancer risk for men (HR, 1.11 per 5-kg increment; 95% CI, 1.03-1.20), but not women (HR, 1.00; 95% CI, 0.94-1.07). Men who gained ≥20 kg from age 18 had an increased risk of colon cancer compared with men whose weight was stable (HR, 1.47; 95% CI, 0.94-2.31).
Weight gain during adult life increases men's risk of colon cancer.
Avoiding excessive weight gain might help reduce colon cancer risk for men.
流行病学研究一致报告了肥胖与男性结肠癌风险之间的正相关关系，但女性的证据则不太一致。很少有研究调查体重变化对结肠癌风险的影响。
我们使用墨尔本协作队列研究，该研究主要招募了年龄在 40 至 69 岁之间的男性和女性，研究了 18 岁时的体重和体重指数（BMI）以及研究入组时的体重与自 18 岁以来的体重变化与结肠癌之间的关系。使用 Cox 回归估计了危险比（HR）和 95％置信区间（CI）。
在平均 16188 名男性和 23438 名女性随访 14 年期间，我们确定了 569 例结肠癌新发病例。研究入组时的体重和 BMI 与男性结肠癌风险呈正相关[每增加 5kg，HR 为 1.12（95％CI，1.04-1.21）；每增加 5kg/m2，HR 为 1.39（95％CI，1.12-1.71）]，但女性则不然。18 岁时的体重或 BMI 与结肠癌风险无关。成年期体重变化与男性结肠癌风险呈正相关（每增加 5kg，HR 为 1.11；95％CI，1.03-1.20），但与女性无关（HR，1.00；95％CI，0.94-1.07）。与体重稳定的男性相比，18 岁后体重增加≥20kg 的男性结肠癌风险增加（HR，1.47；95％CI，0.94-2.31）。
成年期体重增加会增加男性结肠癌的风险。
避免体重过度增加可能有助于降低男性结肠癌的风险。
