Wins and losses: Mapping the GLP-1 receptor’s path
Industry Buzz
[What] often gets overlooked is the effect on sleep apnea. Just losing ~10% [of] body weight can improve airway obstruction during sleep, which affects energy and long-term heart health. These aren't just secondary benefits. For some, these are the reasons to seek treatment in the first place.
—Roberto Valledor, MD, board-certified family medicine physician
[Results of the EVOKE trial] did not tell us that GLP-1 receptor agonists have no impact on the brain; it just tells us we have to be careful about what endpoints we are measuring and in whom.
—Roberto Valledor, MD, board-certified family medicine physician
GLP-1 drugs stopped being a weight story once clinicians observed effects occurring far from adipose tissue.
Over the past 2 years, research has shifted toward the brain, kidney, and cardiovascular system, driven by receptor mapping studies and human outcome data. What looked incidental in early trials now looks directional.
GLP-1 receptors are widely expressed in the central and peripheral nervous system, in areas tied to reward processing and executive control.[] This distribution explains why clinicians keep hearing similar patient reports across practices: reduced cravings, altered alcohol intake, and improved impulse control. Neurology and psychiatry groups now treat such reports as signals worthy of formal study.
Role in addiction medicine
Addiction research sits at the top of the opportunity list.[] Nora Volkow, Director of the National Institute on Drug Abuse, framed the importance of the signal clearly when she noted the fact that we have limited treatment options for substance use disorder, despite its high morbidity, mortality, and economic costs.[]
In 2025, investigators reported results from a RCT of semaglutide in adults with alcohol use disorder. The trial showed a significant reduction in the number of heavy drinking days and weekly alcohol cravings compared with placebo.[]
Similar exploratory work continues in nicotine and opioid use disorders, focused on reward circuitry and cue reactivity. Patients using GLP-1 therapy for metabolic disease increasingly report secondary changes in substance use.
Related: Ozempic and porn: Pharma's strangest plot twist yet?Board-certified family medicine physician Kyle Hoedebecke, MD, a clinical advisor at Alpas Wellness Virginia Drug & Alcohol Rehab in Sterling, VA, says, “Patients often report a quieting of ‘brain noise,’ where the constant mental chatter about cravings simply fades away—and this goes far beyond snacking. Many people find they no longer have the urge for a second glass of wine or their usual cigarette, and from a medical standpoint, this makes total sense. GLP-1 receptors are highly concentrated in the brain's reward centers, and by modulating how dopamine responds to these triggers, the medication essentially blunts the chemical ‘hit’ that addictive substances usually provide, making the behavior feel far less rewarding and helping the cycle break naturally.”
However, we still need more focused research to establish these effects. As Fernando Ovalle Jr., MD, a double board-certified plastic surgeon and obesity medicine specialist, puts it, “Yes, some patients report reduced alcohol interest or fewer craving-driven behaviors, often alongside reduced food noise; however, I don’t frame GLP-1s as addiction treatment. These are early signals, not established indications.”
The neurobiology makes sense, but plausibility isn’t enough. What would shift my confidence are larger randomized trials with concrete clinical endpoints—ie, relapse rates, sustained abstinence—and clear safety data in patients with substance use disorders.
—Fernando Ovalle, Jr., MD, double board-certified plastic surgeon and obesity medicine specialist
Cardiorenal protection
Multiple outcome trials now show reductions in major adverse cardiovascular events among patients with type 2 diabetes and/or obesity.[] Kidney outcomes followed a similar arc. The National Kidney Foundation describes GLP-1 receptor agonists as agents that slow chronic kidney disease and lower cardiovascular risk, particularly when albuminuria is present.
Vivek Gupta, MD, MPH, a board-certified internal medicine physician and obesity medicine specialist says, “One of the most intriguing studies, the SELECT trial, showed a roughly 20% relative reduction in major cardiovascular events—heart attack, stroke, or cardiovascular death—with semaglutide within the first 3 months of the drug, before significant weight loss, suggesting perhaps an anti-inflammatory effect of the GLPs.
"Other studies have also infiltrated the public conversation, including the benefits of obstructive sleep apnea and fatty liver disease,” Dr. Gupta adds.
Practice guidance reflects this evolution. UK Kidney Association guidelines published in 2025 supported the use of GLP-1s across stages of chronic kidney disease, including advanced disease, due to nonrenal clearance and favorable safety profiles.[]
The American College of Cardiology’s 2025 consensus statement also endorsed earlier initiation of obesity pharmacotherapy for patients with cardiometabolic risk, explicitly rejecting step-therapy models requiring lifestyle failure.[] Clinically, this moved GLP-1 drugs from optional adjuncts into first-line risk-modification tools.
Discussing the utility of GLP-1 inhibitors in cardiorenal protection, Dr. Hoedebecke says, “Patients who benefit the most from starting these drugs early are the ones with high-risk conditions, like those who’ve already had a heart attack or are in the middle stages of kidney disease. Specifically, people dealing with heart failure with preserved ejection fraction tend to show a lot of resilience once they start a GLP-1.”
Related: Semaglutide pill shows heart benefits in one key group, study findsSleep apnea
In adults with obesity and obstructive sleep apnea (OSA), incretin-based pharmacotherapy can reduce OSA severity, commonly tracked by apnea-hypopnea index (AHI) and hypoxic burden, in parallel with cardiometabolic improvements.[] The most practice-relevant data are those from the liraglutide randomized clinical trial and the tirzepatide phase 3 trials.[][] A 2025 meta-analysis reported that GLP-1 receptor agonists were more effective vs control at reducing AHI in patients with obesity and/or type 2 diabetes.[]
Roberto Valledor, MD, a board-certified family medicine physician who serves as a collaborating physician for Mochi Health’s telemedicine platform, says, “One [benefit] that often gets overlooked is the effect on sleep apnea. Just losing 10% to 15% [of] body weight can improve airway obstruction during sleep, which affects energy levels and long-term heart health. These are not just secondary benefits. For some people, these are the reasons to seek treatment in the first place.”
Neurology
The most debated frontier remains neurodegeneration. GLP-1 agents attracted attention due to anti-inflammatory effects, insulin signaling in the brain, and animal data suggesting neuroprotection. That enthusiasm met a reality check in Alzheimer’s disease. The phase 3 EVOKE and EVOKE+ trials evaluating oral semaglutide in patients with early Alzheimer’s disease failed to meet primary cognitive endpoints despite biomarker shifts.[] Investigators reported changes in inflammatory markers and tau-related biomarkers without corresponding cognitive separation.
Related: The results are in: What 2 major new studies show about semaglutide and Alzheimer’s“EVOKE failed to improve cognition in people with Alzheimer's—a good example of how something that is effective in a preclinical model may not be effective in a human, particularly when it comes to a disease of the brain, which is a bit of a Pandora's box," Dr. Valledor says.
"It is also a reminder to enroll the right patients. If you are enrolling people with [an] established disease, you are looking at how a drug prevents the disease. If you are enrolling people with [an] established disease, you are looking at whether the drug can reverse it. This does not tell us that GLP-1 receptor agonists have no impact on the brain; it just tells us we have to be careful about what endpoints we are measuring and in whom,” Dr. Valledor says.
“Just because a drug has anti-inflammatory properties does not mean it will be useful in every disease in which there is inflammation. Just because a drug improves insulin sensitivity does not mean it will be useful in every metabolic disorder. We need to study the drug in the disease that we are interested in; we cannot simply extrapolate from other diseases,” he adds.
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