Close to becoming the fastest most commonly sold medication in the US, enter center stage glucagon-like peptide 1 receptor agonists (they signal this receptor) called GLP-1 RA or semaglutides.
Fact: Drugs like Ozempic cost about $20,000 per year.
Fact: A survey by the Kaiser Family Foundation found 12% (or 1 in 8) of U.S. adults have used a GLP-1 drug like Ozempic, Wegovy, or similar medications at some time in their lives.
Fact: GLP-1 is a hormone primarily produced by specialized cells in the colon called enteroendocrine L cells. These cells are located throughout the intestines, mostly in the colon.
Fact: Natural enteroendocrine cells cells produce GLP-1 “not” continuously but in cycles. In pulses. In response to when you eat, especially carbohydrates and fats.
GLP-1 regulates blood sugar. Stimulates insulin secretion. Inhibits glucagon release. Slows down the squeezing of the stomach after meals.
Slowing down the stomach emptying food after you eat.
Fact: Drugs like Ozempic produce “continuous” GLP-1. Unlike how our natural enteroendocrine cells work.
Both GLP-1 made naturally or administered as a medication reduce food intake.
You lose appetite or may even get nauseated for a while while you acclimate.
Some patients swear by these new meds.
In many, not all, they work to help lose weight.
Some functional docs and pharmacists say they were wary, but the results are so striking, they now feel this meds have a real place in medicine.
Medical journal articles are saying these meds should be taught to all med students to give to all obese patients.
Reminiscent of the days when journals called for statins to be put in our water supply.
GLP-1 crosses the blood brain barrier to affect how we regard food. And appetite.
Drugs like Ozempic cross the blood brain barrier, too.
But our own GLP-1 only crosses into the brain in a cyclic manner.
We do not know what constant brain tissue exposure to GLP-1 might do.
The eyes are an extension of our brain.
Fact: What might be one serious side effect from constant exposure to GLP-1?
This suggests that some patients should AVOID these meds if they have any serious issues in these tissues already.
What am I talking about?
Newly appreciated fact: Patients on semaglutides may be at increased risk for an uncommon serious condition that can cause vision loss.
METHODOLOGY:
Retrospective study of 16,827 patients at Massachusetts Eye and Ear in Boston.
Tracked 710 patients with type 2 diabetes (194 of whom had been prescribed semaglutide) and 979 patients with overweight or obesity (361 prescribed semaglutide).
Researchers compared patients prescribed semaglutide with those prescribed a medication other than a GLP-1 agent.
They matched patients by factors such as age and sex, hypertension status, obstructive sleep apnea status, or heart disease status.
They then tracked the cumulative incidence of nonarteritic anterior ischemic optic neuropathy (NAION) during 36 months of follow-up.
This is a disease of the arteries going to the eye that can cause rapid full-on blindness.
My dad had this.
It contributed to the end of him.
It causes such serious blindness that they gave him 180 mg of prednisone for over a year to try to protect his eyes.
On these meds for so long he started to look like a penguin.
His vertebrae began to disintegrate.
He was in horrific pain.
But he still could see.
What a conundrum.
In medicine risk vs. benefit reigns.
TAKEAWAY:
The use of Semaglutides use was associated with a higher risk for NAION in patients with type 2 diabetes.
In patients with overweight or obesity, semaglutide was again linked to a higher risk for NAION.
Among patients with type 2 diabetes, the cumulative incidence of NAION over 36 months was 8.9% for those prescribed semaglutide vs 1.8% among those taking non–GLP-1 medications.
For patients with overweight or obesity, the cumulative incidence of NAION over 36 months was 6.7% for the semaglutide cohort vs 0.8% for those in the other group.
This means that the use of these weight loss meds now being robustly recommended for renal, heart, metabolic and even mood protection, “may” be “not” good for some eyes.
Especially in patients who already have diseases that threaten eye health.
Like type 2 Diabetes. Obesity. Macular degeneration. Glaucoma.
Temporal arteritis is an uncommon inflammatory disease. A very nasty, dangerous one.
If you already have vision issues, you might want to think twice about going on this expensive medication that is now one of the most popular of all times.
The study was published online on July 3 in JAMA Ophthalmology.
Conclusions and relevance: This study's findings suggest an association between semaglutide and NAION.
This was an observational study, not demonstrating definitive causality.
What is your vision worth?
Keep in mind that these results were driven by a relatively small number of NAION cases in the patients exposed to semaglutide. In a neuro-ophthalmology practice.
Neuro-opthalmologist docs are the top of the heap eye docs.
They are double-board certified in BOTH eye and neurology genre’s of medicine.
This study does not establish that semaglutides directly causes NAION.
But it makes you want to pause if you already have eye issues, or diseases that give you vulnerabilities for them.
This study was supported by a grant from Research to Prevent Blindness.
Knowledge is power.
Dr. B.
References:
Risk of Nonarteritic Anterior Ischemic Optic Neuropathy in Patients Prescribed Semaglutide. JAMA Ophthalmol. 2024 Jul 3:e242296
Semaglutide Linked to Cause of Vision Loss - Medscape - July 03, 2024.