Sandler R S
Department of Medicine, University of North Carolina at Chapel Hill, USA.
Gastroenterol Clin North Am. 1996 Dec;25(4):717-35. doi: 10.1016/s0889-8553(05)70271-5.
The striking geographic differences in colorectal cancer incidence and the changes in disease risk among immigrants suggest an important environmental component to colorectal cancer risk. Table 1 lists risk factors for colorectal cancer. The categories in the table are somewhat arbitrary but are designed to provide an overall semiquantitative summary of the current epidemiologic literature. Certain of the most important risk factors (e.g., age, family history) cannot be modified. Individuals at high risk might benefit from surveillance. Dietary factors appear to be among the most important determinants of colorectal cancer risk. Diet helps to explain geographic variation in disease. A diet that is high in red meat and saturated fat appears to increase risk. Vegetables, fruits, fiber, folate, and calcium may be protective. Obesity, particularly abdominal obesity, and tall stature may be risk factors. Physical activity has been repeatedly shown to reduce the risk of colorectal cancer. Postmenopausal hormone replacement therapy may also be protective. Exciting new data suggest a significantly lower risk of colorectal cancer in regular users of aspirin and NSAIDs. It is important to recognize that the use of these drugs can have adverse as well as beneficial effects, and the appropriate dose and timing are not known. Enough information is available to make recommendations to lower the risk of colorectal cancer. Reducing red meat and fat consumption; increasing fruits, vegetables, and grains; avoiding obesity; and adopting a regular program of physical activity reduce the risk of colorectal cancer. Fortunately, these modifications also decrease the risk of cardiovascular disease, an even more important cause of mortality in Western societies.
结直肠癌发病率存在显著的地域差异，且移民人群的疾病风险也有变化，这表明环境因素在结直肠癌风险中起着重要作用。表1列出了结直肠癌的风险因素。表中的类别有些随意，但旨在对当前流行病学文献进行总体的半定量总结。某些最重要的风险因素（如年龄、家族史）无法改变。高危个体可能会从监测中受益。饮食因素似乎是结直肠癌风险的最重要决定因素之一。饮食有助于解释该病的地域差异。红肉和饱和脂肪含量高的饮食似乎会增加风险。蔬菜、水果、纤维、叶酸和钙可能具有保护作用。肥胖，尤其是腹部肥胖，以及身材高大可能是风险因素。体育活动已反复证明可降低结直肠癌风险。绝经后激素替代疗法也可能具有保护作用。令人兴奋的新数据表明，经常使用阿司匹林和非甾体抗炎药的人群患结直肠癌的风险显著降低。必须认识到，使用这些药物可能既有不良影响也有有益效果，而且合适的剂量和用药时间尚不清楚。现有足够的信息可用于提出降低结直肠癌风险的建议。减少红肉和脂肪的摄入量；增加水果、蔬菜和谷物的摄入；避免肥胖；并开展规律的体育活动，可降低患结直肠癌的风险。幸运的是，这些改变也能降低心血管疾病的风险，而心血管疾病在西方社会是更重要的死亡原因。
