Weight-loss drugs show promise for other diseases, study shows

A new study reveals that weight-loss drugs like Ozempic may help treat conditions such as Parkinson’s disease, and addiction. The injectable drug Ozempic is shown, July 1, 2023, in Houston. (AP Photo/David J. Phillip, File)

Weight loss drugs like Ozempic and Wegovy could help treat heart failure, Parkinson’s disease and even addiction, according to a new study from McGill University and the Jewish General Hospital.

The research, published in eClinicalMedicine, reviewed evidence from dozens of studies to assess whether GLP-1 drugs could be beneficial in treating other illnesses.

Areesha Moiz, a research assistant at the Centre of Clinical Epidemiology at the Lady Davis Institute, part of the Jewish General, said some of the findings were surprising.

“It’s quite interesting to see the pleiotropic benefits of this drug beyond what it was designed for,” Moiz said in a recent interview.

She noted researchers wanted to create a roadmap showing where the science is headed regarding GLP-1 drugs.

According to Moiz, the benefits of GLP-1 drugs like Ozempic are now well established for patients with cardiovascular and kidney disease.

Additionally, ongoing clinical studies are investigating their effectiveness in conditions commonly associated with obesity, such as heart failure, sleep apnea, liver disease and knee osteoarthritis.

“But what’s actually interesting is that we found other conditions. We found neurodegenerative diseases, like Alzheimer’s and Parkinson’s, that are also being investigated, as well as addiction, meaning substance abuse disorders,” Moiz said.

“Some of these are linked somewhat to the weight-loss effects, but there are also other mechanisms at play here that are independent of weight loss, which are actually providing some beneficial outcomes in certain populations.”

Moiz explained that GLP-1 receptors are found throughout the body, affecting multiple organ systems.

For example, in type 2 diabetes and obesity, these drugs act on receptors in the pancreas, brain and gut, slowing digestion and suppressing appetite, which leads to blood sugar control and weight loss.

“There’s a certain mechanism where it acts on the reward system of the brain, so that kind of brings down the pleasurable effect of eating. But that’s also kind of related to addiction, right?

“Like alcohol abuse, cigarette smoking, opioid abuse — all of that kind of ties together. So that’s why, because of these receptors and underlying mechanisms, they’re being investigated for other conditions that might also be related to these biological rationales,” she said.

As more benefits are uncovered, Moiz said that serious risks previously feared have largely been ruled out by recent studies. Nevertheless, side effects, especially gastrointestinal, have been observed.

“There are some side effects related to the gallbladder, which have to do with the slowing down the digestion and the rapid weight loss. But this is not as common as you expect,” Moiz said.

“Recently, there were some signals for optic neuropathy and for aspiration risk, but these are, again, very, very rare side effects, and there haven’t been big trials that were designed to really look at this, so we can’t say that the drugs are causing this.”

GLP-1 drugs are quite expensive and are not currently covered by Quebec’s public drug plan unless it is prescribed for diabetes. So Moiz said the first step in making it more accessible is for obesity to be declared a chronic condition by the province, like Alberta did this year.