Sturgeon S R, Brinton L A, Berman M L, Mortel R, Twiggs L B, Barrett R J, Wilbanks G D
Environmental Epidemiology Branch, National Cancer Institute, Bethesda, Maryland 20892.
Br J Cancer. 1993 Sep;68(3):584-9. doi: 10.1038/bjc.1993.390.
We examined the relation between physical activity and endometrial cancer using data from a multicentre case-control study involving 405 endometrial cancer cases and 297 population controls. Estimates of recreational (i.e. active sport, walks and hikes) and nonrecreational activity (i.e. house cleaning, climbing stairs and walking or standing on the job) were obtained using interview information. After adjustment for age, study area, education, parity, years of use of oral contraceptives, years of use of menopausal oestrogens and cigarette smoking, recent recreational inactivity was associated with increased risk (RR = 1.9 for lowest vs highest tertile). Similarly, recent nonrecreational inactivity was associated with increased risk (RR = 2.2 for lowest vs highest tertile). Further adjustment for body mass and nonrecreational activity attenuated the association between risk and recent recreational inactivity (RR = 1.2; 95% CL = 0.7-2.0) but adjustment for body mass and recreational activity did not alter the association between risk and recent nonrecreational inactivity (RR = 2.0; 95% CL = 1.2-3.1). To evaluate the relation between risk and sustained inactivity, we simultaneously examined activity levels at three periods (RR i.e. age 20-29, age 30-39 and recently) in women age 50 and older. After adjustment for potential confounders and body mass, risk was elevated among women who were always recreationally inactive (RR = 1.5 for always active vs always inactive) and among women who were always nonrecreationally inactive (RR = 1.6 for always active vs always inactive). This study suggests that physically inactive women may be at increased risk of endometrial cancer because they are more likely to be overweight or obese. Our data also suggest that inactivity per se may be associated with an increased risk of endometrial cancer. However, we cannot rule out the possibility that our results, particularly those for nonrecreational activity, reflect unmeasured confounding factors. Future studies should attempt to obtain more detailed assessments of physical activity, including the intensity with which an individual engaged in an activity and the actual time involved in exertion.
我们利用一项多中心病例对照研究的数据，对体育活动与子宫内膜癌之间的关系进行了研究。该研究纳入了405例子宫内膜癌病例和297名人群对照。通过访谈信息获取了娱乐性活动（即积极的运动、散步和徒步旅行）和非娱乐性活动（即房屋清洁、爬楼梯以及工作时行走或站立）的相关估计数据。在对年龄、研究地区、教育程度、生育状况、口服避孕药使用年限、绝经后雌激素使用年限以及吸烟情况进行调整后，近期娱乐性活动不足与风险增加相关（最低三分位数与最高三分位数相比，相对风险RR = 1.9）。同样，近期非娱乐性活动不足也与风险增加相关（最低三分位数与最高三分位数相比，RR = 2.2）。进一步对体重和非娱乐性活动进行调整后，风险与近期娱乐性活动不足之间的关联减弱（RR = 1.2；95%可信区间CL = 0.7 - 2.0），但对体重和娱乐性活动进行调整并未改变风险与近期非娱乐性活动不足之间的关联（RR = 2.0；95% CL = 1.2 - 3.1）。为了评估风险与持续性活动不足之间的关系，我们同时考察了50岁及以上女性在三个时期（即20 - 29岁、30 - 39岁以及近期）的活动水平。在对潜在混杂因素和体重进行调整后，始终缺乏娱乐性活动的女性（始终活跃与始终不活跃相比，RR = 1.5）以及始终缺乏非娱乐性活动的女性（始终活跃与始终不活跃相比，RR = 1.6）的风险升高。这项研究表明，缺乏体育活动的女性患子宫内膜癌的风险可能会增加，因为她们更有可能超重或肥胖。我们的数据还表明，活动不足本身可能与子宫内膜癌风险增加有关。然而，我们不能排除这样一种可能性，即我们的结果，尤其是那些关于非娱乐性活动的结果，反映了未测量的混杂因素。未来的研究应该尝试对体育活动进行更详细的评估，包括个人参与活动的强度以及实际运动时间。
