Yazd Cardiovascular Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Department of Nutrition and Public Health, School of Public Health, North Khorasan University of Medical Sciences, Bojnurd, Iran.
Sci Rep. 2021 Jan 28;11(1):2479. doi: 10.1038/s41598-021-81671-0.
Although obesity has been associated with an increased cancer risk in the general population, the association in patients with type 2 diabetes (T2D) remains controversial. We conducted a dose-response meta-analysis of cohort studies of body mass index (BMI) and the risk of total and site-specific cancers in patients with T2D. A systematic literature search was conducted in PubMed, Scopus, and Medline until September 2020 for cohort studies on the association between BMI and cancer risk in patients with T2D. Summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated using random effects models. Ten prospective and three retrospective cohort studies (3,345,031 participants and 37,412 cases) were included in the meta-analysis. Each 5-unit increase in BMI (kg/m) was associated with a 6% higher risk of total cancer (RR: 1.06, 95% CI 1.01, 1.10; I = 55.4%, n = 6), and with a 12% increased risk in the analysis of breast cancer (RR: 1.12, 95% CI 1.05, 1.20; I = 0%, n = 3). The pooled RRs showed no association with prostate cancer (RR: 1.02, 95% CI 0.92, 1.13; I = 64.6%, n = 4), pancreatic cancer (RR: 0.97, 95% CI 0.84, 1.11; I = 71%, n = 3), and colorectal cancer (RR: 1.05, 95% CI 0.98, 1.13; I = 65.9%, n = 2). There was no indication of nonlinearity for total cancer (P = 0.99), however, there was evidence of a nonlinear association between BMI and breast cancer (P = 0.004) with steeper increases in risk from a BMI around 35 and above respectively. Higher BMI was associated with a higher risk of total, and breast cancer but not with risk of other cancers, in patients with T2D, however, further studies are needed before firm conclusions can be drawn.
尽管肥胖与一般人群的癌症风险增加有关，但在 2 型糖尿病（T2D）患者中的相关性仍存在争议。我们对 T2D 患者的体重指数（BMI）与总癌症和特定部位癌症风险的队列研究进行了剂量反应荟萃分析。在 PubMed、Scopus 和 Medline 中进行了系统的文献检索，以查找关于 T2D 患者 BMI 与癌症风险之间关联的队列研究，截至 2020 年 9 月。使用随机效应模型计算汇总相对风险（RR）和 95%置信区间（CI）。荟萃分析纳入了 10 项前瞻性和 3 项回顾性队列研究（3345031 名参与者和 37412 例病例）。BMI 每增加 5 个单位（kg/m），总癌症风险增加 6%（RR：1.06，95%CI 1.01，1.10；I=55.4%，n=6），乳腺癌风险增加 12%（RR：1.12，95%CI 1.05，1.20；I=0%，n=3）。合并 RR 与前列腺癌（RR：1.02，95%CI 0.92，1.13；I=64.6%，n=4）、胰腺癌（RR：0.97，95%CI 0.84，1.11；I=71%，n=3）和结直肠癌（RR：1.05，95%CI 0.98，1.13；I=65.9%，n=2）均无关联。总癌症无非线性关系的迹象（P=0.99），但是 BMI 与乳腺癌之间存在非线性关联的证据（P=0.004），BMI 在 35 左右和以上时风险增加更为陡峭。T2D 患者的 BMI 与总癌症和乳腺癌风险增加相关，但与其他癌症风险无关，但需要进一步研究才能得出明确的结论。
