Ozempic and Alzheimer's Disease
Semaglutide (aka Ozempic, Wegovy, Rybelsus) may reduce the risk of developing Alzheimer's Disease
What do Ozempic, Wegovy and Rybelsus all have in common? First of all, they’re all made by the same company - Novo Nordisk and they’re actually all the same drug too - semaglutide, a GLP-1 receptor agonist but one is an oral tablet (Rybelsus) while the other two are injectables (Ozempic, Wegovy).
You have probably heard of Ozempic by now because it’s the diabetes drug that also helps with weight loss. Officially, Ozempic, IS for diabetes and Wegovy is for weight management. Rybelsus? Officially for diabetes but will help with weight loss too.
Recently, the following publication in the journal Alzheimer’s & Dementia: The Journal of Alzheimer’s Association suggested that patients with diabetes taking semaglutide (oral or injectable) had a significantly lower risk of developing Alzheimer’s Disease:
The study is based on a massive database of electronic health records (EHRs) encompassing 116 million patients across the United States of which about 1 million eligible patients were identified for an analysis comparing semaglutide with 7 other diabetes drugs.
What they found was that patients with no known history of Alzheimer’s who had diabetes and took semaglutide (any formulation) were less likely to have a first-time diagnosis of Alzheimer’s compared to 7 other diabetes medications, including drugs that are actually in the same drug class as semaglutide (this class of drugs is called GLP1-receptor agonists). Some names you may recognize that belong in this class are Victoza (liraglutide) and Trulicity (dulaglutide). So compared to insulin, the risk was about 67% lower and compared to other GLP-1 receptor agonists, the risk was 41% lower.
Is semaglutide protective against Alzheimer’s then? Maybe? Current research is definitely pointing in that direction and it’s convincing enough that there are now 2 ongoing phase 3 trials looking at the neuroprotective effects of oral semaglutide in early Alzheimer’s Disease that are expected to finish in 2026.
But what about the other drugs in the same family? So far, there is some suggestion that GLP-1 receptor agonists as a class may protect cognitive function and data pooled from randomized controlled trials and nationwide prescription registers from Denmark suggest a 53% reduction in dementia in those with type 2 diabetes taking GLP-1 receptor agonists.
We don’t know exactly why these drugs may be neuroprotective but there are some theories. GLP-1 receptor agonists are used to treat diabetes right? Yes, they mimic the effects of a natural hormone called GLP-1 which regulates blood sugar levels and other metabolic function:
They enhance insulin secretion from the pancreas in a glucose-dependent manner (eg. only when blood sugar levels are elevated)
They suppress glucagon, a hormone that raises blood sugar
They delay gastric emptying (by slowing the rate at which food leaves the stomach, you have a slower rise in blood sugar after meals)
They make you feel more full and they reduce appetite
But how is this related to Alzheimer’s? There is supposedly a link between insulin resistance and Alzheimer’s actually. Heard of the term, “Type 3 Diabetes”? It’s an unofficial term used to describe the proposed relationship between Alzheimer’s and insulin resistance in the brain. If this theory is correct, Alzheimer’s Disease may be a neuroendrocrine disorder stemming from impairments in insulin signalling in the central nervous system. After all, many studies have shown that diabetes and insulin resistance are major risk factors for Alzheimer’s.
Emerging studies also suggest that the benefits of GLP-1 receptor agonists extend beyond glycemic control and it is hypothesized that they can reduce neuro-inflammation, oxidative stress, plaques (amyloid-beta plaques are a hallmark of Alzheimer’s), tau protein tangles (another hallmark of Alzheimer’s) and stimulate the growth of new neurons, support cell proliferation in brain regions critical for memory and learning (like the hippocampus), and enhance the brain’s ability to adapt and form new connections, all of which are neuroprotective.
Sound promising right? I’m looking forward to seeing the results of the semaglutide trials!
Excellent informative article.