Chiu B C-H, Gapstur S M, Chow W-H, Kirby K A, Lynch C F, Cantor K P
Department of Preventive Medicine, Northwestern University Medical School, Chicago, IL, USA.
Int J Obes (Lond). 2006 Jun;30(6):940-7. doi: 10.1038/sj.ijo.0803231.
To investigate the association between obesity and risk of renal cell carcinoma and to examine whether the association is modified by physical activity.
A population-based case-control study of 406 patients with renal cell carcinoma and 2434 controls conducted in Iowa.
Information was collected on weight at the ages 20-29, 40-49, and 60-69 years, height, nonoccupational physical activity, diet, and other lifestyle factors. Renal cell carcinoma risk was estimated by odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for age, total energy intake, and other confounding factors.
Height and total energy intake were not associated with risk in either sex. In men, neither physical activity nor level of obesity in any period of life was significantly associated with risk. In women, lower physical activity was associated with higher risk (OR=2.5; 95% CI=1.2-5.2 comparing exercise <1 time/month to >1 time/day). Compared with women in the lowest quartile for BMI, the risks of renal cell carcinoma for women in the highest 10% of BMI in their 20s, 40s, and 60s were 1.4 (CI=0.6-3.1), 1.9 (CI=0.9-4.2), and 2.3 (CI=0.9-6.0), respectively. When analyses were limited to self-respondent data, the corresponding ORs were 2.9 (CI=1.2-7.4), 3.2 (CI=1.3-7.5), and 2.1 (CI=0.7-6.4), respectively. There was little evidence that physical activity modifies the association of BMI with renal cell carcinoma.
Nonoccupational physical activity was inversely associated and obesity was positively associated with risk of renal cell carcinoma among women. The risk appeared to be greater for women in the highest 10% of BMI in their 40s. Our finding of little evidence of an interaction between physical activity and BMI requires confirmation.
研究肥胖与肾细胞癌风险之间的关联，并探讨这种关联是否会因体力活动而改变。
在爱荷华州进行的一项基于人群的病例对照研究，纳入406例肾细胞癌患者和2434例对照。
收集20 - 29岁、40 - 49岁和60 - 69岁时的体重、身高、非职业性体力活动、饮食及其他生活方式因素等信息。通过比值比（OR）和95%置信区间（CI）估计肾细胞癌风险，并对年龄、总能量摄入及其他混杂因素进行校正。
身高和总能量摄入在两性中均与风险无关。在男性中，任何生命阶段的体力活动和肥胖程度均与风险无显著关联。在女性中，较低的体力活动与较高风险相关（与每月锻炼<1次相比，每天锻炼>1次，OR = 2.5；95% CI = 1.2 - 5.2）。与20多岁、40多岁和60多岁时BMI处于最低四分位数的女性相比，BMI处于最高10%的女性患肾细胞癌的风险分别为1.4（CI = 0.6 - 3.1）、1.9（CI = 0.9 - 4.2）和2.3（CI = 0.9 - 6.0）。当分析仅限于自我应答数据时，相应的OR分别为2.9（CI = 1.2 - 7.4）、3.2（CI = 1.3 - 7.5）和2.1（CI = 0.7 - 6.4）。几乎没有证据表明体力活动会改变BMI与肾细胞癌之间的关联。
在女性中，非职业性体力活动与肾细胞癌风险呈负相关，肥胖与肾细胞癌风险呈正相关。40多岁时BMI处于最高10%的女性风险似乎更高。我们发现几乎没有证据表明体力活动与BMI之间存在相互作用，这一发现需要进一步证实。
