Obesity is a rising cause of cancers in the United States and globally. It is projected to overtake tobacco use as the largest cause of cancer in the United States in the future. So we were interested in finding strategies to reduce the risk of obesity-related cancers. GLP-1 receptor agonists, we thought, were a promising candidate, they’ve revolutionised the treatment of obesity and related comorbidities but they haven’t definitively been shown to protect against obesity-associated cancers.

So in this study we compared these GLP-1 medications to DPP-4 inhibitors, another diabetes medication that doesn’t affect weight. We were interested to see if a composite outcome of 13 obesity-related cancers was reduced. We ultimately found that it was by 7% compared to DPP-4 inhibitors.

What was the methodology and what were the findings?

The methodology, again, we took 85,000 patients who were first starting GLP-1 agonists from a large electronic health record database and we took 85,000 people starting this other class of medications, these DPP-4 inhibitors. We matched each GLP-1 user with a DPP-4 user based on clinical characteristics, demographics, medication history, so that we had two comparable groups. Then we looked over the course of an average of 3.9 years to see the rates of obesity-related cancers in these patients taking these two diabetes drugs. We also looked at all cause death and the rates of individual obesity-related cancers as well.

What are the clinical implications of these findings?

The impact of these findings is that this shows that GLP-1 agonist drugs are associated, at least, with a decreased risk of a number of major cancer causes of mortality such as colorectal cancer, pancreatic cancer, when analysed as a composite. The actual risk reduction we found in our study is relatively modest so the overall clinical impact of this study alongside other studies that have looked at this question are that it’s reassuring that GLPs at least are unlikely to increase the risk of cancer and they may have some modest oncologic benefit on top of the known benefits in cardiovascular disease, chronic kidney disease, obesity etc.