Metformin use associated with decreased risk of colorectal cancer

the Oncology Nurse Advisor take:

According to a new study published in the journal Cancer, researchers from the University of Chicago in Chicago, Illinois, have found that metformin use is associated with a decreased risk of developing colorectal cancer.

Metformin is typically the first-line oral treatment for patients with type 2 diabetes mellitus. For the study, researchers sought to examine the effects of metformin on colorectal cancer incidence in a U.S. population. 

Using MarketScan databases, researchers identified patients with diabetes and colorectal cancer with each case being matched with up to two controls. The mean age of participants was 57 years for cases and 55 years for controls.

Results showed that metformin use was associated with a 15% risk reduction for the development of colorectal cancer, which was reduced to 12% after adjusting for health care use.

Researchers also found that there was no significant association between metformin dose, duration of treatment, or total exposure and risk of colorectal cancer.