BACKGROUND AND AIMS Recent increases in colorectal cancer (CRC) incidence in adults younger than 50 years of age have led to more colonoscopies in this age group. As a result, there may be an increasing number of adults <50 years old with polyps detected. There is concern that younger adults may require closer follow-up. Our goal was to use data from the New Hampshire Colonoscopy Registry (NHCR) to examine the risk for metachronous advanced adenomas (AAs) and large (>1 cm) serrated polyps in younger versus older adults who return for a follow-up colonoscopy. METHODS Our cohort consisted of NHCR participants with at least 1 polyp on index examination and a follow-up colonoscopy at least 1 year after the index examination. Outcomes were the risks for metachronous AAs (adenomas ≥1 cm, with villous elements or high-grade dysplasia, or CRC) and large (≥1 cm) serrated polyps. We present absolute risk and adjusted risks from a logistic regression model stratified by age at index colonoscopy (<40, 40-49, 50-59, and 60+ [reference]). Covariates included index findings, endoscopist adenoma detection rates, sex, smoking, body mass index, follow-up time (months), bowel preparation quality, and family history of CRC. RESULTS In our sample of 12,380 adults, absolute risk for metachronous AA was lower for younger patients than for patients aged ≥60. After adjusting for covariates, when comparing with the 60+ group (reference), the lowest risk was observed in those younger than 40 years (odds ratio, .19; 95% confidence interval, .05-.80). Of note, similar risks were observed in the 40 to 49 age group (odds ratio, .61; 95% confidence interval, .41-.92) and 50 to 59 age group (odds ratio, .71; 95% confidence interval, .58-.86). The risk for large metachronous serrated polyps was not associated with age. CONCLUSIONS Younger adults aged <40 with index adenomas had a lower risk for metachronous AAs than those aged ≥60. The 40- to 49-year age group was found to have metachronous risk similar to the 50- to 59-year age group, with both less than the ≥60 age group. These data suggest that current surveillance interval guidelines for patients aged ≥50 years may appropriately be used with younger adults.

中文翻译：

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年轻人和异时性瘤形成：与老年人相比，未来发生晚期腺瘤和锯齿状息肉的风险更大。

背景和目的年龄在50岁以下的成年人中结直肠癌（CRC）发病率的近期增长已导致该年龄组的结肠镜检查增多。结果，发现息肉的年龄<50岁的成年人可能会越来越多。有人担心年轻人可能需要更密切的随访。我们的目标是使用新罕布什尔州结肠镜检查注册处（NHCR）的数据来检查返回随访结肠镜检查的年轻成年人与老年人的异时性晚期腺瘤（AAs）和大（> 1 cm）锯齿状息肉的风险。方法我们的队列由NHCR参与者组成，这些参与者在指标检查中至少有1例息肉，并在指标检查后至少1年进行了结肠镜检查。结果是发生异位AA（腺瘤≥1 cm，伴有绒毛成分或高度不典型增生，或CRC）和大（≥1 cm）的锯齿状息肉。我们通过按结肠镜检查年龄（<40、40-49、50-59和60+ [参考]）年龄分层的逻辑回归模型显示绝对风险和调整后的风险。协变量包括指数发现，内镜腺瘤检出率，性别，吸烟，体重指数，随访时间（月），肠道准备质量和CRC家族史。结果在我们的12,380名成人样本中，年轻患者的异时AA绝对风险低于60岁以上的患者。校正协变量后，与60岁以上的人群（参考）进行比较，在40岁以下的人群中观察到最低的风险（优势比，.19； 95％置信区间，.05-.80）。值得注意的是，在40至49岁年龄段的人群中观察到了类似的风险（优势比为0.61； 95％的置信区间为0.41-。92岁）和50至59岁年龄段的人（赔率，.71； 95％置信区间，.58-.86）。大型异时锯齿状息肉的风险与年龄无关。结论年龄小于40岁且患有指数腺瘤的年轻人比60岁以上的年轻人发生异位AA的风险更低。40至49岁年龄组的异时风险与50至59岁年龄组相似，且均小于或等于60岁年龄组。这些数据表明，对于年龄≥50岁的患者，当前的监护间隔指南可能适合年轻人使用。40至49岁年龄组的异时风险与50至59岁年龄组相似，且均小于或等于60岁年龄组。这些数据表明，对于年龄≥50岁的患者，当前的监护间隔指南可能适合年轻人使用。40至49岁年龄组的异时风险与50至59岁年龄组相似，且均小于或等于60岁年龄组。这些数据表明，对于年龄≥50岁的患者，当前的监护间隔指南可能适合年轻人使用。