GLP-1 drugs beyond weight loss: heart, kidney, liver and sleep apnoea
GLP-1 medicines such as semaglutide and tirzepatide are now approved in the US to cut heart, kidney and liver risks and to treat sleep apnoea. Not every hope has held up: a large Alzheimer's trial failed in 2025.
GLP-1 drugs are no longer only weight-loss medicines. Between 2024 and 2025, US regulators approved semaglutide or tirzepatide to reduce heart attacks and strokes, slow kidney disease, treat a serious form of fatty liver disease and ease obstructive sleep apnoea. At the same time, a large trial in Alzheimer's disease showed no benefit, a reminder that the drugs do not work for everything.
What are GLP-1 drugs?
GLP-1 drugs are medicines that mimic a gut hormone, glucagon-like peptide-1, which helps control blood sugar and appetite. The best-known are semaglutide (sold as Ozempic for type 2 diabetes and Wegovy for weight management) and tirzepatide (Mounjaro and Zepbound), which also acts on a second hormone, GIP. They were first developed for diabetes, then approved for obesity. Their use has grown so fast that the World Health Organization issued its first guideline on them in December 2025, noting that obesity affects more than 1 billion people and was associated with 3.7 million deaths worldwide in 2024.
Do GLP-1 drugs protect the heart?
Yes, for a specific group: adults with established cardiovascular disease and overweight or obesity. The US Food and Drug Administration approved Wegovy for this use on 8 March 2024, calling it the first weight-loss medicine approved to reduce the risk of cardiovascular death, heart attack and stroke. The decision rested on a double-blind trial of more than 17,600 people. Major adverse cardiovascular events occurred in 6.5% of those on Wegovy and 8% of those on placebo.
Can they slow kidney and liver disease?
Trials show they can, in people with diabetes-related kidney disease and in a form of fatty liver disease. On 28 January 2025, the FDA approved Ozempic to reduce the risk of worsening kidney disease, kidney failure and cardiovascular death in adults with type 2 diabetes and chronic kidney disease. In the FLOW trial of 3,533 adults, semaglutide cut that combined risk by 24% compared with placebo, an absolute reduction of 4.9% over three years.
In August 2025, Wegovy received accelerated approval for metabolic dysfunction-associated steatohepatitis (MASH), an inflammatory liver disease, in adults with moderate to advanced fibrosis but not cirrhosis. In the first part of the ESSENCE trial, steatohepatitis resolved in 63% of patients on semaglutide versus 34% on placebo, and liver fibrosis improved in 37% versus 22%. Accelerated approval means the company must confirm the benefit on longer-term outcomes. Diet still matters for liver and metabolic health; our explainer on what the science says about the Mediterranean diet covers that evidence.
What about sleep apnoea?
Tirzepatide is approved to treat moderate to severe obstructive sleep apnoea in adults with obesity. The FDA approved Zepbound for this use on 20 December 2024, the first medicine cleared for the condition. Two 52-week trials in 469 adults without type 2 diabetes found a significant reduction in the apnoea-hypopnoea index, a measure of breathing pauses during sleep, compared with placebo. Poor breathing at night fragments sleep; for context on what healthy sleep looks like, see how much sleep adults actually need.
| Condition | Drug | FDA decision | Key trial result |
|---|---|---|---|
| Heart attack, stroke, cardiovascular death | Wegovy (semaglutide) | March 2024 | Events in 6.5% vs 8% on placebo |
| Obstructive sleep apnoea | Zepbound (tirzepatide) | December 2024 | Significant fall in breathing pauses vs placebo |
| Kidney disease with type 2 diabetes | Ozempic (semaglutide) | January 2025 | 24% lower risk of kidney and heart outcomes |
| MASH liver disease (no cirrhosis) | Wegovy (semaglutide) | August 2025 (accelerated) | Resolution in 63% vs 34% on placebo |
Where have GLP-1 drugs fallen short?
The clearest failure so far is Alzheimer's disease. On 24 November 2025, Novo Nordisk reported that its evoke and evoke+ trials, which enrolled 3,808 people aged 55 to 85 with mild cognitive impairment or mild dementia due to Alzheimer's, did not show that semaglutide slowed the disease. Some Alzheimer's-related biomarkers improved, but that did not translate into a delay in cognitive or functional decline, and a planned one-year extension was cancelled.
Other suggested uses, including addiction and some psychiatric conditions, are still being studied and are not approved indications. Observational studies can hint at benefits, but only randomised trials can show cause and effect.
What are the known risks?
The most common side effects are digestive, such as nausea, vomiting and diarrhoea, and rarer serious risks are listed on the product labels. In 2025, the European Medicines Agency concluded that an eye condition called NAION, which can cause sudden vision loss, is a very rare side effect of semaglutide, affecting up to 1 in 10,000 users. The WHO advises anyone with sudden vision loss or rapidly worsening eyesight to contact a doctor immediately. The WHO guideline also makes its recommendation for obesity treatment conditional, citing limited long-term data, high cost and unequal access; it projects the drugs will reach fewer than 10% of those who could benefit by 2030.
Frequently asked questions
Is Ozempic the same as Wegovy?
Both contain semaglutide, but they are separate products approved for different purposes and at different strengths. Ozempic is approved for type 2 diabetes and, in the US, for reducing cardiovascular and kidney risks in people with diabetes. Wegovy is approved for weight management and, in the US, for cutting heart risks and treating MASH liver disease in certain adults.
Do GLP-1 drugs work for Alzheimer's disease?
Not on current evidence. Two large trials of oral semaglutide in early Alzheimer's disease, with 3,808 participants, did not slow cognitive or functional decline compared with placebo, according to results announced in November 2025. Some biomarkers improved, but that did not lead to a measurable clinical benefit, and the planned extension was cancelled.
Are GLP-1 drugs approved for sleep apnoea?
In the United States, tirzepatide (Zepbound) was approved in December 2024 for moderate to severe obstructive sleep apnoea in adults with obesity, alongside diet and exercise. It was the first medicine approved for the condition. Approvals differ between countries, so a doctor can explain what applies where you live.
Do the heart benefits apply to everyone who takes these drugs?
No. Wegovy's cardiovascular approval covers adults who already have cardiovascular disease and either obesity or overweight. In the trial behind it, major heart events fell from 8% on placebo to 6.5% on Wegovy. The evidence does not show the same benefit in people without existing heart disease.
What does the WHO say about GLP-1 drugs?
In December 2025, the WHO issued its first guideline on GLP-1 medicines for obesity. It conditionally recommends liraglutide, semaglutide or tirzepatide for long-term treatment of obesity in adults, except pregnant women, and suggests offering structured diet and exercise support. It calls the recommendation conditional because long-term data, cost and access remain concerns.
Sources
- US FDA — FDA approves first treatment to reduce risk of serious heart problems specifically in adults with obesity or overweight (8 March 2024)
- US FDA — FDA approves first medication for obstructive sleep apnea (20 December 2024)
- Novo Nordisk via BioSpace — FDA approves Ozempic to reduce the risk of worsening kidney disease (28 January 2025)
- HCPLive — FDA approves semaglutide (Wegovy) 2.4 mg for noncirrhotic MASH (15 August 2025)
- Alzheimer Europe — Novo Nordisk announces topline results from the evoke and evoke+ trials (24 November 2025)
- WHO — The use of semaglutide medicines and risk of NAION (27 June 2025)
- WHO — WHO issues global guideline on the use of GLP-1 medicines in treating obesity (1 December 2025)
More to read
Measles comeback: why the US could lose its elimination status in 2026
Measles has returned to countries that once eliminated it, driven by gaps in vaccination. The US has confirmed more than 5,000 cases in 2026, and regional health experts are reviewing its elimination status this week.
How much sleep do adults need? Seven to nine hours, experts reaffirm
Most adults need at least seven hours of sleep a night, and the main expert ranges are seven to nine hours, or seven to eight after 65. A 2026 review of a decade of research left those ranges unchanged.
First year above 1.5C: 2024 crossed the line, and 2026 is set to follow
2024 was the first calendar year more than 1.5C warmer than pre-industrial times. Copernicus says 2026 is virtually certain to be the second, but the Paris Agreement limit refers to a 20-year average, not single years.