GLP-1 drugs: a promising new frontier for cancer risk reduction

Glucagon-like peptide-1 receptor agonists (GLP-1) drugs offer an extremely effective option for many to lose weight — but their effects on health don’t stop there. Researchers are just starting to appreciate the protective health effects that these therapies could have beyond the scale. Having excessive body fat is often linked to serious health concerns, such as type 2 diabetes, cardiovascular disease, and certain types of cancers. One of the most common surgical treatments for severe obesity is bariatric metabolic surgery (BMS), which has been shown to reduce the rate of obesity-related cancers (ORC) (1,2). Whether or not GLP-1 drugs can also reduce the risk for ORC has remained unclear (3). Now, a recent publication revealed that patients that took GLP-1 drugs share similarly reduced ORC rates compared to BMS (4).

“Both obesity and diabetes are major concerns, in health systems and for societies,” said Yael Wolff-Sagy, an epidemiologist at Clalit Health Services and first author of the study. “It’s always on the table in my professional experience.”

Understanding the study on GLP-1 and cancer risk

Wolff-Sagy’s team started by collecting electronic medical records from patients who either had BMS or started first-generation GLP-1 drugs between the years of 2010 and 2018. They matched these patients to form 3,178 pairs based on sex, weight, age, treatment windows, and other existing medical conditions. They followed these patients for an average of 7.2 years, where they monitored health status, treatments, and specific ORCs like multiple myeloma, meningioma, and adenocarcinoma of the kidneys, thyroid, GI tract, and reproductive systems.

“ORCs account for around 40 percent of all cancer diagnoses in the US, and the incidence of these has been rising particularly in young adults aged 25-49,” shared Sonali Thosani, a medical doctor at MD Anderson Cancer Center, who was not involved in this study.

This study highlights an important point that weight loss is not the only factor in cancer risk reduction in the setting of GLP-1 therapy.
- Sonali Thosani, MD Anderson Cancer Center

The most common BMS recorded were sleeve gastrectomy and gastric bypass, while the majority of patients taking GLP-1 treatments used liraglutide, one of the earliest GLP-1 drugs on the market.

“Although the lack of newer generation GLP-1s is a limitation of the current study, the evaluation of first generation GLP-1s remains of relevance in nowadays clinical practice around the world,” Wolff-Sagy noted.

Among 298 patients who were diagnosed with an ORC during the follow-up period, 77 (26 percent) were diagnosed with breast cancer, 49 (16 percent) were diagnosed with colon or rectum cancer, and 45 (15 percent) were diagnosed with uterine cancer.

The surprising link between GLP-1 and reduced cancer risk

These rates of cancer were almost identical to the BMS group. “We have ORC in 5.62 cases per 1,000 persons in the BMS group and 5.89 cases per 1,000 persons in the GLP-1 group,” said Wolff-Sagy.

The researchers also found that the mean weight loss between groups was significantly different, with those who had BMS having a 31.1 percent weight reduction and those taking GLP-1s having only a 12.9 percent reduction.

Considering how weight loss is known to reduce ORC rates, Wolff-Sagy conducted an analysis that simulates the incidence of ORC if those taking GLP-1 drugs lost the same amount of weight as BMS patients. She stated that GLP-1 treatment had a 41 percent relative risk reduction compared to BMS and suggested that GLP-1 drugs may contribute to reducing ORC risk in other ways, like reducing inflammation or modulating the immune system.

“This study highlights an important point that weight loss is not the only factor in cancer risk reduction in the setting of GLP-1 therapy,” said Thosani. “It is possible, as the authors imply, that there might be some other anti-inflammatory benefits that are having an outcome on cancer risk reduction.”

Wolff-Sagy shared that future work would involve looking at other cohort studies, expanding the demographics and timeframe of the study, and digging into the molecular mechanisms behind GLP-1 treatments.

“When data is available for retrospective studies, I think it's important to use it,” said Wolff-Sagy. “It can answer some questions that are very difficult to answer in other ways.”

Frequently asked questions about GLP-1 drugs

What are GLP-1 drugs?

GLP-1 drugs, or glucagon-like peptide-1 receptor agonists, are a class of medications primarily used to treat type 2 diabetes and promote weight loss. They work by mimicking a hormone that regulates appetite and insulin release.

Do GLP-1 drugs help prevent cancer?

A recent study showed that patients who took GLP-1 drugs had a similar reduction in the risk of obesity-related cancers compared to patients who underwent bariatric surgery. This suggests that GLP-1 treatments may offer a protective effect against certain cancers.

Is the cancer risk reduction solely due to weight loss from GLP-1 drugs?

No. The study found that patients on GLP-1 drugs had significantly less weight loss than those who had bariatric surgery, but a nearly identical reduction in cancer risk. This suggests that GLP-1 may have additional anti-inflammatory or immune-modulating benefits that contribute to cancer risk reduction.

Are these GLP-1 drugs the same as newer medications like Ozempic and Wegovy?

The study focused on first-generation GLP-1 drugs like liraglutide. While the findings are promising, further research is needed to determine if newer-generation medications like Ozempic (semaglutide) and Mounjaro (tirzepatide) have similar cancer-reducing effects.

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