[title]：Relationship between colorectal adenomas and serum lipids; hypo-trigriceridemia is an independent preventive factor for colorectal tubular adenoma in male

 

[Author]　Masafumi Tabuchi

 

[Back ground]  Many epidemiological papers have been published on the relation of lipids and the incidence of colorectal adenoma and cancer. Their conclusions sometimes indicated opposite directions to each other. The present predominant theory is that high level of lipids, both cholesterol and trigriceride, promote the incidence of colonic tumors. To vote this controversy, a large scale study was performed from the about 30000 consecutive clean colon endoscopic procedures. After we submitted the abstract, a fine statistic analysis using JUMP soft ware was made and the results of this study were slightly changed.

[Method and objects] All adenomas and mucosal cancers were removed in almost every colonoscopy. High resolution magnified chromo-endoscope was used to avoid failing to detect adenoma and cancers. More than twenty minutes were spent for the detection in each colonoscopy. Before the colonoscopy, the level of serum lipids (cholesterol and trigriceride) was measured. The objects were limited to the cases that underwent colonoscopy more than three times. The cases were about 3000 in number. The average age was about 57 and gender rate was 26%. They were divided into groups according to the average of lipid level. We counted the incidence of adenoma and mucosal cancer in each groups.    

[Results] Serum cholesterol levels were not associated with the frequency of colorectal adenoma and mucosal cancer. On the contrary, serum triglyceride levels were associated with the frequency of colorectal adenoma and mucosal cancer. Under the level of 150mg/dl, the lower the level of triglyceride, the lower the incidence was. The odds ratio was 2.5. Over the level of 150mg/dl, there was no tendency.(cf. tables and figures)

[Conclusion] Our data was not consistent with the present predominant theory about cholesterol level, but was consistent with that about triglyceride level. Low level of trigriceride is supposed to be a preventive factor against occurrence of colorectal neoplasm.