全球肥胖负担不断增加，结直肠癌 (CRC) 发病率和死亡率也在增加。旨在评估亚洲人群中体重指数 (BMI) 与 CRC 事件风险和 CRC 相关死亡之间的关联。这项队列研究包括数据汇集了亚洲队列联盟中包含的 17 项前瞻性队列研究。队列入组时间为1984年1月1日至2002年12月31日。中位随访时间为15.2年（IQR，12.1-19.2年）。数据分析时间为 2023 年 1 月 15 日至 2024 年 1 月 15 日。体重指数，计算方法为体重（公斤）除以身高（米）的平方。主要结局是 CRC 发病率和 CRC 相关死亡率。使用 Cox 比例风险回归模型，将事件风险报告为 CRC 事件和 CRC 死亡的调整后风险比 (AHR) 和 95% CI。为了评估 CRC 事件的风险，619 981 名参与者（平均 [SD] 年龄，该研究纳入了 53.8 [10.1] 岁；52.0% 女性；11 900 例确诊的 CRC 病例，并评估了 650 195 名参与者（平均 [SD] 年龄；51.9% 女性） ; 4550 例已确诊的 CRC 死亡病例被纳入该研究。在BMI大于25.0至27.5 (AHR, 1.09 [95% CI, 1.03-1.16])、大于27.5至30.0 (AHR, 1.19 [95% CI, 1.03-1.16])的参与者中观察到BMI与CRC风险之间呈正相关。 1.11-1.29]），与 BMI 大于 23.0 至 25.0 的人相比，其大于 30.0（AHR，1.32 [95% CI，1.19-1.46]）（趋势 P < .001），并且 BMI 与与直肠癌相比，结肠癌的风险增加更大。在 BMI 大于 27.5 的参与者中观察到 BMI 与 CRC 相关死亡风险之间存在类似关联（BMI >27.5-30.0：AHR，1.18 [95% CI，1.04-1.34]；BMI >30.0：AHR，1.38 [95 % CI, 1.18-1.62]；P < .001（趋势））并且存在于 BMI 大于 30.0 的男性中（AHR，1.87 [95% CI，1.49-2.34]；P < .001（趋势）），但不存在于 BMI 大于 30.0 的男性中女性（趋势 P = .15）（异质性 P = .02）。在这项队列研究中，对包括亚洲参与者的 17 项队列研究进行了汇总分析，发现 BMI 与 CRC 发病率和相关死亡率之间存在正相关关系。患有结肠癌的男性和参与者的风险更大。这些发现可能有助于更好地了解亚洲人群肥胖对结直肠癌发病率和相关死亡的负担。

The global burden of obesity is increasing, as are colorectal cancer (CRC) incidence and mortality.To assess the association between body mass index (BMI) and risks of incident CRC and CRC-related death in the Asian population.This cohort study includes data pooled from 17 prospective cohort studies included in The Asia Cohort Consortium. Cohort enrollment was conducted from January 1, 1984, to December 31, 2002. Median follow-up time was 15.2 years (IQR, 12.1-19.2 years). Data were analyzed from January 15, 2023, through January 15, 2024.Body mass index, calculated as weight in kilograms divided by height in meters squared.The primary outcomes were CRC incidence and CRC-related mortality. The risk of events is reported as adjusted hazard ratios (AHRs) and 95% CIs for incident CRC and death from CRC using the Cox proportional hazards regression model.To assess the risk of incident CRC, 619 981 participants (mean [SD] age, 53.8 [10.1] years; 52.0% female; 11 900 diagnosed incident CRC cases) were included in the study, and to assess CRC-related mortality, 650 195 participants (mean [SD] age, 53.5 [10.2] years; 51.9% female; 4550 identified CRC deaths) were included in the study. A positive association between BMI and risk of CRC was observed among participants with a BMI greater than 25.0 to 27.5 (AHR, 1.09 [95% CI, 1.03-1.16]), greater than 27.5 to 30.0 (AHR, 1.19 [95% CI, 1.11-1.29]), and greater than 30.0 (AHR, 1.32 [95% CI, 1.19-1.46]) compared with those with a BMI greater than 23.0 to 25.0 (P < .001 for trend), and BMI was associated with a greater increase in risk for colon cancer than for rectal cancer. A similar association between BMI and CRC-related death risk was observed among participants with a BMI greater than 27.5 (BMI >27.5-30.0: AHR, 1.18 [95% CI, 1.04-1.34]; BMI >30.0: AHR, 1.38 [95% CI, 1.18-1.62]; P < .001 for trend) and was present among men with a BMI greater than 30.0 (AHR, 1.87 [95% CI, 1.49-2.34]; P < .001 for trend) but not among women (P = .15 for trend) (P = .02 for heterogeneity).In this cohort study that included a pooled analysis of 17 cohort studies comprising participants across Asia, a positive association between BMI and CRC incidence and related mortality was found. The risk was greater among men and participants with colon cancer. These findings may have implications to better understand the burden of obesity on CRC incidence and related deaths in the Asian population.