Guilera Magda, Connelly-Frost Alexandra, Keku Temitope O, Martin Christopher F, Galanko Joseph, Sandler Robert S
Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill 27599, USA.
Nutr Cancer. 2005;51(2):140-5. doi: 10.1207/s15327914nc5102_3.
Although both physical inactivity and obesity have been associated with an increased risk of colorectal adenomas, it is unclear whether physical activity modifies the relationship between obesity and colorectal adenomas or through what mechanism this might occur. The aim of this study is to evaluate whether physical activity modifies the relationship between body mass index (BMI) and colorectal adenomas and whether apoptosis is a plausible mechanism responsible for this effect modification. Study subjects were part of a large, cross-sectional study, the Diet and Health Study III. Consecutive patients underwent colonoscopy between August 1998 and March 2000. Apoptosis was measured by morphological evaluation of hematoxylin and eosin-stained sections obtained from rectal pinch biopsy samples. There were 226 patients with adenomas and 494 adenoma-free controls. When comparing overweight subjects with the referent group (high physical activity/normal BMI), the relative odds of having an adenoma decreased as physical activity increased: low (odds ratio, OR=1.6; 95% confidence interval, CI=0.7-3.4); moderate (OR=1.1; 95% CI=0.6-2.0); and high (OR=0.8; 95% CI=0.4-1.6). When comparing obese subjects with the referent group, relative odds of having an adenoma were increased regardless of physical activity level. Apoptosis was not associated with obesity or physical activity. Our results suggest that physical activity may modify the association between obesity and colorectal adenoma until a high level of obesity is achieved. Apoptosis does not appear to be associated with obesity or physical activity.
尽管缺乏身体活动和肥胖都与结直肠腺瘤风险增加有关，但尚不清楚身体活动是否会改变肥胖与结直肠腺瘤之间的关系，以及这可能通过何种机制发生。本研究的目的是评估身体活动是否会改变体重指数（BMI）与结直肠腺瘤之间的关系，以及细胞凋亡是否是导致这种效应改变的合理机制。研究对象是一项大型横断面研究“饮食与健康研究III”的一部分。1998年8月至2000年3月期间连续的患者接受了结肠镜检查。通过对从直肠钳取活检样本获得的苏木精和伊红染色切片进行形态学评估来测量细胞凋亡。有226例腺瘤患者和494例无腺瘤对照。当将超重受试者与参照组（高身体活动/正常BMI）进行比较时，随着身体活动增加，患腺瘤的相对比值比下降：低（比值比，OR = 1.6；95%置信区间，CI = 0.7 - 3.4）；中度（OR = 1.1；95% CI = 0.6 - 2.0）；和高（OR = 0.8；95% CI = 0.4 - 1.6）。当将肥胖受试者与参照组进行比较时，无论身体活动水平如何，患腺瘤的相对比值比均增加。细胞凋亡与肥胖或身体活动无关。我们的结果表明，在达到高度肥胖之前，身体活动可能会改变肥胖与结直肠腺瘤之间的关联。细胞凋亡似乎与肥胖或身体活动无关。
