Metformin use has been associated with a decreased incidence and mortality of various cancers.
Dr Soo-Jeong Cho and colleagues from Korea evaluated the association between metformin use and gastric cancer.
The research team randomly selected 100,000 type 2 diabetic patients from the 2004 Korean National Health Insurance claim database, and assessed gastric cancer incidence among 39,989 patients who were regularly treated with anti-diabetic drugs, and followed-up from 2004 to 2010.
In total, 26,690 patients had used metformin out of 32,978 diabetics who had not regularly used insulin, and 5855 patients had used metformin out of 7011 regular insulin users.
|In insulin non-users, the adjusted hazard ratio (AHR) for metformin use was 0.73 |
|Alimentary Pharmacology & Therapeutics|
The researchers found that patients who used metformin showed a lower incidence of gastric cancer than those who did not use metformin, in insulin non-users.
The team noted that in patients on regular insulin, there was no difference of gastric cancer incidence according to metformin use.
In insulin non-users, the adjusted hazard ratio (AHR) for metformin use was 0.73 with borderline statistical significance.
The team found that duration of metformin use was associated with the reduction in gastric cancer risk, especially in patients who used metformin for more than 3 years.
Dr Cho's team concludes, "Metformin use >3 years in type 2 diabetics who do not use insulin is associated with a significantly reduced gastric cancer risk."