Adapted from Wang QL et al. American Journal of Gastroenterology 1st January 2020
Metformin users were at a lower risk of developing oesophageal squamous carcinoma than non metformin users.
A growing number of observational studies have shown that metformin reduces overall cancer risk and a few specific cancer types such as colon, rectal, breast and stomach.
A population based cohort study included over 400,000 metformin and an equal number of non metformin users who were matched by age and sex.
There were 3.5 cases of oesophageal cancer in the metformin group per 100,000 person/years and 5.3 in the non metformin group. This finding was true for men, women and those in their sixties. The odds ratio was 0.68 for metformin use.