Glucagon-like peptide 1 (GLP-1) receptor agonists may be effective at reducing the risk of colorectal cancer in patients with a higher body mass index (BMI) and diabetes, according to a recent study published by Wang et al in JAMA Oncology.
Background
Obesity is a chronic health condition that raises the risk of developing cardiovascular disease—the leading cause of death in the United States—and may be linked to type 2 diabetes. Patients with overweight, obesity, and diabetes may also have an increased risk of developing colorectal cancer, which is the third-leading type of cancer and second-leading cause of cancer mortality in the United States with 153,000 new cases and 52,550 deaths per year. The National Institutes of Health (NIH) identifies patients with certain levels of fat cells as having overweight and obesity. The conditions are common across the United States and are caused by several factors—including a poor diet, lack of sleep, low physical activity, genetics, and a family history.
Physicians use BMI to measure body fat based on height and weight. Nearly 75% of U.S. adults aged 20 years or older may have either overweight or obesity, and nearly 20% of children and adolescents aged 2 to 19 years have obesity, according to the NIH.
GLP-1 receptor agonists—often administered as injections to treat patients with type 2 diabetes—are designed to lower blood-sugar levels, improve insulin sensitivity, and help manage weight. The agents have also been shown to reduce the rates of major adverse cardiac events. Notably, patients with or without overweight or obesity may experience the protective effects of GLP-1 receptor agonists.
“To our knowledge, this is the first indication this popular weight-loss and antidiabetic class of drugs reduces incidence of [colorectal cancer], relative to other antidiabetic agents,” explained co–senior study author Rong Xu, PhD, Professor at the School of Medicine at the Case Western Reserve University.
Study Methods and Results
In the new population-based study, investigators used a national database comprising over 100 million electronic health records to examine the outcomes of 1.2 million patients who had been treated with GLP-1 receptor agonists from 2005 to 2019. The investigators examined the effects of GLP-1 receptor agonists compared with other antidiabetic agents on their incidence of colorectal cancer.
Among the 22,572 patients with diabetes who had received insulin, the investigators identified 167 cases of colorectal cancer. Among the 22,572 matched patients treated with GLP-1 receptor agonists, they identified 94 cases of colorectal cancer—representing a 44% reduction in the incidence of the disease.
In a similar analysis, the investigators evaluated 18,518 patients with diabetes who received metformin compared with 18,518 patients with diabetes treated with GLP-1 receptor agonists. They found that those who had received the GLP-1 receptor agonists had a 25% decreased incidence of colorectal cancer.
Conclusions
“Our results clearly demonstrate that GLP-1 [receptor agonists] are significantly more effective than popular antidiabetic drugs—such as metformin or insulin—at preventing the development of [colorectal cancer],” emphasized co–senior study author Nathan Berger, MD, the Hanna-Payne Professor of Experimental Medicine at the School of Medicine at the Case Western Reserve University. “The research is critically important for reducing incidence of [colorectal cancer] in patients with diabetes, with or without overweight and obesity,” he underscored.
The new findings indicated the need for clinical trials to determine whether GLP-1 receptor agonists could prevent colorectal cancer. The researchers hope that the antidiabetic agents can also prevent other types of cancer associated with obesity and diabetes.
Disclosure: For full disclosures of the study authors, visit jamanetwork.com.
