结直肠癌（CRC）筛查的益处可能需要10到15年才能累积。因此，建议对健康状况良好的老年人进行筛查。为确定年龄在75岁以上、预期寿命少于10年的患者进行的肠镜检查数量、诊断产率以及手术后10天和30天内发生的不良事件等信息。本综合性研究与嵌套队列于2009年1月至2022年1月在一家综合性医疗系统进行，评估了门诊接受筛查性肠镜检查的75岁以上无症状患者。排除有不完整数据、除筛查之外的任何指征、在过去5年内接受过肠镜检查、以及个人有炎症性肠病或CRC病史的患者。预计寿命是基于之前的文献预测模型。主要结果是接受筛查的患者中预期寿命受限（<10年）的百分比。其他结果包括肠镜检查结果以及手术后10天和30天内发生的不良事件。共纳入了7067名年龄在75岁以上的患者。中位数（四分位间距）年龄为78（77-79）岁，其中3967名（56％）为女性，5431名（77％）为白人，平均有2种共患疾病（从一组选择的共患疾病中获取）。在76至80岁年龄组中，接受肠镜检查的预期寿命少于10年的患者占30％，不分性别，随着年龄的增长而增加-81至85岁男性的比例为82％，女性的比例为61％（总共71％），85岁以上的患者100％。不良事件需要住院治疗，在10天内常见（每1000例中有13.58例），随着年龄的增长而增加，特别是在85岁以上的患者中。高级结肠疾病的检测率在76至80岁患者中为5.4％，在81至85岁患者中为6.2％，在85岁以上患者中为9.5％（P = .02）。在总人口中，有15名患者（0.2％）患有浸润性腺癌；在预期寿命少于10年的患者中，有9人中的1人接受了治疗，而在预期寿命大于或等于10年的6名患者中有4名接受了治疗。在这个综合性研究与嵌套队列中，大多数针对75岁以上的患者的筛查性肠镜检查是在有限的寿命下进行，与增加的并发症风险相关。结直肠癌极为罕见。

The benefits from colorectal cancer (CRC) screening may take 10 to 15 years to accrue. Therefore, screening is recommended for older adults who are in good health.To determine the number of screening colonoscopies done in patients older than 75 years with a life expectancy of fewer than 10 years, diagnostic yield, and associated adverse events within 10 days and 30 days of the procedure.This cross-sectional study with a nested cohort between January 2009 and January 2022 in an integrated health system assessed asymptomatic patients older than 75 years who underwent screening colonoscopy in the outpatient setting. Reports with incomplete data, any indication other than screening, patients who had a colonoscopy within the previous 5 years, and patients with a personal history of inflammatory bowel disease or CRC were excluded.Life expectancy based on a prediction model from previous literature.The primary outcome was the percentage of screened patients who had limited (<10 years) life expectancy. Other outcomes included colonoscopy findings and adverse events that developed within 10 days and 30 days of the procedure.A total of 7067 patients older than 75 years were included. The median (IQR) age was 78 (77-79) years, 3967 (56%) were women, and 5431 (77%) were White with an average of 2 comorbidities (taken from a select group of comorbidities). The proportion of colonoscopies performed on patients with a life expectancy of fewer than 10 years aged 76 to 80 years was 30% in both sexes and increased with age-82% of men and 61% of women aged 81 to 85 years (71% total), and 100% of patients beyond the age of 85 years. Adverse events requiring hospitalizations were common at 10 days (13.58 per 1000) and increased with age, particularly among patients older than 85 years. The detection of advanced neoplasia varied from 5.4% among patients aged 76 to 80 years to 6.2% in those aged 81 to 85 years and 9.5% among patients older than 85 years (P = .02). Of the total population, 15 patients (0.2%) had invasive adenocarcinoma; among patients with a life expectancy of fewer than 10 years, 1 of 9 was treated, whereas 4 of 6 patients with a life expectancy of greater than or equal to 10 years were treated.In this cross-sectional study with a nested cohort, most screening colonoscopies performed in patients older than 75 years were in patients with limited life expectancy and associated with increased risk of complications. Colorectal cancer was exceedingly rare.