Department of Chinese Traditional Medicine, The Second Hospital of Shaoxing, Shaoxing, Zhejiang, China.
Department of Hand Surgery, The Second Hospital of Tangshan, Tangshan, Hebei Province, China.
J Cancer Res Clin Oncol. 2021 Dec;147(12):3591-3599. doi: 10.1007/s00432-021-03790-5. Epub 2021 Sep 6.
Recent Mendelian randomization (MR) studies derived inconsistent results of blood lipids' effect on colorectal cancer, and whether the blood lipids' effect on colon and rectal cancer is different is still unknown. Here, we sought to answer these questions.
Primarily, we employed univariable MR to explore the blood lipids' effect on colon and rectal cancer, including high-density lipoprotein (HDL), low-density lipoprotein (LDL), total cholesterol and triglycerides. Then, multivariable MR was also employed to reassess each blood lipid's effect on the two cancers with adjustment of the other lipids. Reverse MR analysis was adopted to determine whether colon or rectal cancer could affect the levels of blood lipids. The Cochrane's Q value was used to evaluate the heterogeneity, and MR-PRESSO was used to appraise the pleiotropy.
Generally, we did not find any significant result between blood lipids and the colon/rectal cancer after Bonferroni correction in the univariable MR analysis. The multivariable MR analysis also obtained the same results. However, it should be noted that higher total cholesterol level might increase the risk of colon cancer (OR = 1.15 [1.01, 1.31], IVW p value = 0.029) but not rectal cancer (OR = 1.02 [0.85, 1.21], IVW p value = 0.853). Such causal relationship turned insignificant in the multivariable MR. The reverse MR analysis suggested that either colon or rectal cancer could increase the levels of blood lipids.
We found no association between blood lipids and risk of colon or rectal cancer, except for a positive association between total cholesterol and colon cancer risk.
最近的孟德尔随机化（MR）研究得出了血脂对结直肠癌影响的不一致结果，血脂对结肠癌和直肠癌的影响是否不同仍不清楚。在这里，我们试图回答这些问题。
首先，我们采用单变量 MR 来探讨血脂对结肠癌和直肠癌的影响，包括高密度脂蛋白（HDL）、低密度脂蛋白（LDL）、总胆固醇和甘油三酯。然后，我们还采用多变量 MR 来调整其他脂质后重新评估每种血脂对两种癌症的影响。采用反向 MR 分析来确定结肠癌或直肠癌是否会影响血脂水平。我们采用 Cochrane's Q 值来评估异质性，并用 MR-PRESSO 来评估多效性。
一般来说，在单变量 MR 分析中，我们没有发现经过 Bonferroni 校正后血脂与结肠癌/直肠癌之间存在任何显著关系。多变量 MR 分析也得到了相同的结果。然而，值得注意的是，较高的总胆固醇水平可能会增加结肠癌的风险（OR=1.15[1.01,1.31]，IVW p 值=0.029），但不会增加直肠癌的风险（OR=1.02[0.85,1.21]，IVW p 值=0.853）。这种因果关系在多变量 MR 中变得不显著。反向 MR 分析表明，结肠癌或直肠癌都可能会增加血脂水平。
我们没有发现血脂与结肠癌或直肠癌风险之间存在关联，除了总胆固醇与结肠癌风险之间存在正相关关系。
