Inhibitory Effect of Metformin Therapy on the Incidence of Colorectal Advanced Adenomas in Patients With Diabetes

Abstract

Background/AimsMetformin use has been associated with decreased colorectal cancer risk and mortality among diabetic patients. Recent research suggests that metformin use may decrease the incidence of colorectal adenomas in diabetic patients with previous colorectal cancer. This study aimed to assess the clinical effect of metformin use on the development of colorectal adenomas in diabetic patients without previous colorectal cancer.MethodsAmong 604 consecutive diabetic patients who underwent colonoscopic surveillance after initial colonoscopy between January 2002 and June 2012, 240 patients without previous colorectal cancer were enrolled in this study and were divided in two groups: 151 patients receiving metformin and 89 patients not receiving metformin. Patient demographics and clinical characteristics as well as the colorectal adenoma incidence rate were retrospectively analyzed.ResultsThe incidence rate of total colorectal adenomas was not different according to metformin use (P=0.349). However, the advanced adenoma incidence rate was significantly lower in the metformin group compared with the non-metformin group (relative risk [RR], 0.09; P=0.011). Metformin use was independently associated with a decreased incidence of advanced colorectal adenomas after adjustment for clinically relevant factors (RR, 0.072; P=0.016). In addition, the cumulative development rate of advanced adenomas during follow-up was significantly lower in the metformin group compared with the non-metformin group (P=0.007).ConclusionsMetformin use in diabetic patients without previous colorectal cancer is associated with a lower risk of advanced colorectal adenomas.

Metformin use and the risk of colorectal adenoma: A systematic review and meta‐analysis

“…Ultimately, 10 studies were deemed appropriate for inclusion in our systematic review and meta‐analysis . These studies had been published between 2008 and 2016, and their enrollment periods ranged from 1998 to 2014.…”

“…These studies had been published between 2008 and 2016, and their enrollment periods ranged from 1998 to 2014. Of the studies included, three were case–control studies, and six were retrospective cohort studies . The remaining one was a randomized controlled trial .…”

“…Among the nine observational studies (case–control and retrospective cohort studies), five were considered being high quality . In addition, the randomized controlled trial by Higurashi et al .…”

Postoperative adjuvant chemotherapy is associated with a lower incidence of colorectal adenomas in patients with previous colorectal cancer

“…In terms of cancer prevention, previous studies have investigated the preventive effect of aspirin, statins, metformin, and other medications used for other chronic diseases in the development of cancer and precancerous lesions, including colorectal adenoma. [7][8][9][10][11][12] Most patients with cancer are treated with chemotherapy with postoperative adjuvant or palliative aim. However, the effect of this chemotherapy on the precancerous lesions of many cancers is unknown.…”

Are Hemorrhoids Associated with False-Positive Fecal Immunochemical Test Results?

“…However, CRC remains the third most common cancer in Western countries, and its incidence is rapidly increasing, especially in Asia 345. Therefore, prevention and early detection of CRC has emerged as an important global issue, and many countries are conducting population-based CRC screening programs by means of fecal immunochemical tests (FITs).…”