KL and digestive system cancer: Moreover, we did a further trend test for serum Klotho and cancer, based on the OR value, and found that with the increase of serum Klotho level, its negative effect on these cancers was significantly enhanced [cancer (p‐trend): pan‐cancer (p‐trend <0.0001), hormone‐related cancer (p‐trend <0.0001), prostate cancer (p‐trend <0.0001), skin cancer (p‐trend <0.0001), digestive system cancer (p‐trend <0.0001), colon cancer (p‐trend = 0.0002)].