Division of Digestive Diseases, David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
Clin Gastroenterol Hepatol. 2009 Nov;7(11):1217-23; quiz 1143. doi: 10.1016/j.cgh.2009.07.013. Epub 2009 Jul 22.
BACKGROUND & AIMS: One objective of colonoscopy is to identify and remove polyps-this process requires attention to detail and prolonged concentration. Providers are predisposed to cognitive errors because the procedure is often performed repetitively throughout the day. We measured the adjusted relationship between colonoscopy start time and polyp yield.
We performed a prospective study of 477 patients that received screening, surveillance, or diagnostic colonoscopies at a Veteran's Administration (VA) teaching hospital. The primary outcome measure was polyp yield. We collected data on colonoscopy start times, which were analyzed both as a dichotomous time period ("early-morning case" vs "later case") and as a continuous variable (start time). We identified significant risk factors using univariate analysis and performed Poisson multivariable regression to measure the independent effect of colonoscopy start time on polyp yield. We evaluated evidence of decreasing polyp yield as the day progressed throughout pre-specified time intervals.
In univariate analysis, early-morning cases yielded 27% more polyps per patient than later cases (95% confidence interval, 11%-45%; P < .001). The total numbers of, hyperplastic and adenomatous polyps found decreased hour-by-hour as the day progressed. Multivariable analysis demonstrated that early-morning cases yielded 20% more polyps per patient than later cases (95% confidence interval, 5%-38%; P = .007).
At a VA medical center, more polyps were detected in patients that received colonoscopies early in the morning compared with later in the day. Moreover, adenoma detection reduced as the day progressed. Providers might be most adept at detecting polyps at the beginning of the day; further validation in other practice settings is required.
结肠镜检查的目的之一是识别和切除息肉-这一过程需要注重细节和长时间的集中注意力。由于该程序通常在一天中反复进行，因此提供者容易出现认知错误。我们测量了结肠镜检查开始时间与息肉产量之间的调整关系。
我们对在退伍军人事务部（VA）教学医院接受筛查、监测或诊断性结肠镜检查的 477 名患者进行了前瞻性研究。主要结局指标是息肉产量。我们收集了结肠镜检查开始时间的数据，将其分析为二项时间期（“清晨病例”与“后期病例”）和连续变量（开始时间）。我们使用单变量分析识别出显著的危险因素，并进行泊松多变量回归，以测量结肠镜检查开始时间对息肉产量的独立影响。我们评估了随着时间的推移，在预先指定的时间间隔内，息肉产量逐渐减少的证据。
在单变量分析中，清晨病例的每位患者的息肉产量比后期病例多 27%（95%置信区间，11%-45%；P<.001）。随着时间的推移，每小时发现的总息肉数、增生性息肉和腺瘤性息肉数量逐渐减少。多变量分析表明，清晨病例的每位患者的息肉产量比后期病例多 20%（95%置信区间，5%-38%；P=0.007）。
在退伍军人事务医疗中心，与当天晚些时候相比，清晨接受结肠镜检查的患者发现的息肉更多。此外，随着时间的推移，腺瘤的检出率降低。提供者可能在一天的开始时最擅长检测息肉；需要在其他实践环境中进一步验证。
