Brenner Darren R, Shaw Eileen, Yannitsos Demetra H, Warkentin Matthew T, Brockton Nigel T, McGregor S Elizabeth, Town Susanna, Hilsden Robert J
Department of Cancer Epidemiology and Prevention Research, CancerControl Alberta, Alberta Health Services, Calgary, Alberta, Canada; Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Department of Oncology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
Department of Cancer Epidemiology and Prevention Research, CancerControl Alberta, Alberta Health Services, Calgary, Alberta, Canada.
Cancer Epidemiol. 2018 Apr;53:12-20. doi: 10.1016/j.canep.2017.12.017. Epub 2018 Jan 30.
Regular recreational moderate to vigorous physical activity (rMVPA) has been previously associated with a reduced risk of colorectal cancer (CRC), however, few studies have examined the association of rMVPA with colorectal polyps, the pre-malignant precursor lesions. The objective of this study was to examine the associations between physical activity and sitting time and polyps at the time of screening.
We conducted a cross-sectional study of 2496 individuals undergoing screening-related colonoscopy in Calgary, Alberta, Canada. Physical activity and sitting time were characterized using hours of rMVPA, meeting physical activity recommendations and hours of sitting time using self-reported data obtained from the International Physical Activity Questionnaire. Logistic regression models were used to estimate the crude and adjusted odds ratios (OR) for presence of polyps associated with rMVPA and sitting time.
Meeting physical activity guidelines of ≥150 min/week was non-significantly associated with a modest decrease in odds of having ≥1 polyp at screening (OR = 0.95, 95% CI: 0.80-1.14). In males, threshold effects for sitting time were observed for up to 20 h/week (OR per hour sitting = 1.07, 95% CI: 1.01-1.13). In stratified analysis, larger inverse associations were observed between physical activity and the presence of polyps in females, obese individuals, and ever smokers, compared to pooled findings.
In this large CRC screening population, there was a suggestive association between increased rMVPA and reduced prevalence of polyps at screening, particularly among females. Even low amounts of regular sitting time (0-20 h/day) were associated with the presence of polyps, particularly among males. Further research on rMVPA and sitting time is necessary to better inform strategies to reduce the frequency of pre-malignant colorectal lesions.
以往研究表明，规律的中度至剧烈休闲体育活动（rMVPA）与降低结直肠癌（CRC）风险相关，但很少有研究探讨rMVPA与癌前病变结直肠息肉之间的关联。本研究旨在探讨筛查时体育活动、久坐时间与息肉之间的关联。
我们对加拿大艾伯塔省卡尔加里市2496例接受与筛查相关结肠镜检查的个体进行了横断面研究。使用rMVPA小时数、达到体育活动建议量以及通过国际体育活动问卷获得的自我报告数据来描述体育活动和久坐时间。采用逻辑回归模型估计与rMVPA和久坐时间相关的息肉存在的粗比值比（OR）和调整后比值比。
达到每周≥150分钟的体育活动指南与筛查时息肉≥1个的几率适度降低无显著关联（OR = 0.95，95%CI：0.80 - 1.14）。在男性中，观察到久坐时间长达每周20小时的阈值效应（每久坐1小时的OR = 1.07，95%CI：1.01 - 1.13）。在分层分析中，与汇总结果相比，体育活动与女性、肥胖个体和曾经吸烟者息肉存在之间的负相关更强。
在这个大型结直肠癌筛查人群中，rMVPA增加与筛查时息肉患病率降低之间存在提示性关联，尤其是在女性中。即使是少量的规律久坐时间（0 - 20小时/天）也与息肉存在相关，尤其是在男性中。有必要对rMVPA和久坐时间进行进一步研究，以更好地为降低结直肠癌前病变发生率的策略提供信息。
