Moyad M A
Department of Surgery, University of Michigan Medical Center, Ann Arbor 48109-0330, USA.
Semin Urol Oncol. 2001 Nov;19(4):270-9.
Obesity has been shown to increase the risk or be associated with numerous conditions from cardiovascular disease and type II diabetes to erectile dysfunction and osteoarthritis. Obesity may also be associated with numerous cancers, and kidney cancer or renal-cell cancer (RCC) may have one of the strongest correlations to obesity compared with cancer at any other site. Almost every epidemiologic investigation has demonstrated an association that tends to affect women more than men, but both genders are impacted. In general, past studies suggest that with increasing weight, a threshold point exists whereby a certain range of body mass index dramatically changes risk. Men and women at the most extreme ends of obesity tend to have the highest risk or only risk in past studies. Individuals at the more extreme ends of obesity may be affected by an almost indefinite number of mechanisms and exposures that could determine incidence and possibly prognosis. For example, higher estrogen levels, elevated insulin levels, a greater concentration of growth factors in adipose tissue, hypertension, cholesterol metabolism abnormalities, and immune malfunction are just some of the potential mechanisms that may increase kidney cancer risk. Obese individuals may also have lower serum levels of vitamin D and engage in less physical activity. Smoking or genetic predisposition to RCC may synergistically contribute to the effect of obesity on risk. The potential mechanisms and associations are numerous and complex. Regardless of the actual cancer risk now and in the future, the overall effect of obesity on general health is clear, and this should be kept in mind in the discussion between health professional and patient.
肥胖已被证明会增加风险或与多种疾病相关，从心血管疾病、II型糖尿病到勃起功能障碍和骨关节炎。肥胖还可能与多种癌症相关，与其他任何部位的癌症相比，肾癌或肾细胞癌（RCC）与肥胖的相关性可能最强。几乎每一项流行病学调查都表明存在一种关联，这种关联往往对女性的影响大于男性，但两性都会受到影响。一般来说，过去的研究表明，随着体重增加，存在一个阈值点，在该点上，一定范围的体重指数会显著改变风险。在过去的研究中，处于肥胖最极端状态的男性和女性往往风险最高或仅有风险。处于肥胖更极端状态的个体可能会受到几乎无数种机制和暴露因素的影响，这些因素可能决定发病率，甚至可能影响预后。例如，较高的雌激素水平、升高的胰岛素水平、脂肪组织中更高浓度的生长因子、高血压、胆固醇代谢异常和免疫功能紊乱只是一些可能增加肾癌风险的潜在机制。肥胖个体的血清维生素D水平也可能较低，且身体活动较少。吸烟或肾癌的遗传易感性可能会协同增加肥胖对风险的影响。潜在的机制和关联众多且复杂。无论现在和未来实际的癌症风险如何，肥胖对总体健康的总体影响是明确的，在健康专业人员与患者的讨论中应牢记这一点。
