Key points
- The SELECT trial showed semaglutide 2.4 mg reduced major cardiovascular events by 20 per cent
- Benefits were observed independently of weight loss, suggesting direct cardiovascular effects
- NICE approved Wegovy for cardiovascular risk reduction in April 2026, expanding eligibility to 1.2 million additional patients
- GLP-1 therapies improve multiple cardiac risk factors: blood pressure, cholesterol, inflammation and blood sugar
- These medications complement — not replace — existing heart medications
Why cardiovascular health matters in obesity
Cardiovascular disease remains the leading cause of death in the United Kingdom. According to the British Heart Foundation, approximately 7.6 million people in the UK live with cardiovascular disease, and obesity is one of the most significant modifiable risk factors.
Excess body weight contributes to high blood pressure, elevated cholesterol, chronic inflammation and insulin resistance — all of which accelerate atherosclerosis and increase the risk of heart attack and stroke. For years, weight management has been recommended as part of cardiovascular risk reduction, but until recently, no weight loss medication had demonstrated a direct reduction in cardiovascular events in a large-scale trial.
That changed with the publication of the SELECT trial results in 2023, marking a pivotal moment in how clinicians think about obesity treatment and cardiac protection.
The SELECT trial: what it showed
The Semaglutide Effects on Cardiovascular Outcomes in People with Overweight or Obesity (SELECT) trial was a landmark double-blind, randomised, placebo-controlled study published in the New England Journal of Medicine in November 2023. It enrolled 17,604 adults across 41 countries.
Who was included
- Adults aged 45 and over with a BMI of 27 or above
- Established cardiovascular disease (previous heart attack, stroke, or peripheral artery disease)
- No diabetes (this was specifically a non-diabetic population)
What the trial measured
The primary endpoint was MACE-3: a composite of cardiovascular death, non-fatal heart attack and non-fatal stroke. Participants received either semaglutide 2.4 mg (the same dose used in Wegovy) or placebo by weekly subcutaneous injection, in addition to standard cardiovascular care.
The results
| Outcome | Semaglutide | Placebo | Risk reduction |
|---|---|---|---|
| MACE-3 (primary endpoint) | 6.5% | 8.0% | 20% |
| Cardiovascular death | Lower | Higher | 15% (trending) |
| Non-fatal heart attack | Lower | Higher | 28% |
| Non-fatal stroke | Lower | Higher | 7% (not significant) |
| Heart failure events | Lower | Higher | 18% |
The mean follow-up was 39.8 months (just over 3 years). Crucially, the cardiovascular benefit appeared to emerge early — within the first 12 months of treatment — and was sustained throughout the trial.
Key finding: The cardiovascular benefits were observed across all weight-loss subgroups, including participants who lost relatively little weight. This suggests that semaglutide has direct cardioprotective effects beyond those attributable to weight loss alone.
How GLP-1 medications protect the heart
Research suggests that GLP-1 receptor agonists such as semaglutide exert cardiovascular benefits through multiple mechanisms, not solely through weight reduction.
Anti-inflammatory effects
Chronic low-grade inflammation plays a central role in atherosclerosis. The SELECT trial measured C-reactive protein (CRP) — a marker of systemic inflammation — and found that semaglutide reduced CRP levels by approximately 38 per cent. This anti-inflammatory effect may help stabilise atherosclerotic plaques and reduce the risk of plaque rupture, which causes most heart attacks.
Blood pressure reduction
GLP-1 medications consistently reduce systolic blood pressure by 3 to 6 mmHg on average. While this may seem modest, at a population level, even small reductions in blood pressure translate into meaningful reductions in cardiovascular events. The blood pressure benefit appears partly independent of weight loss.
Lipid improvements
Semaglutide reduces triglycerides by approximately 15 to 20 per cent and modestly improves LDL cholesterol and HDL cholesterol profiles. These lipid changes contribute to an overall improvement in the atherogenic profile.
Improved glycaemic control
Even in non-diabetic individuals, semaglutide improves insulin sensitivity and reduces fasting glucose levels. Insulin resistance is an independent risk factor for cardiovascular disease, and improving metabolic health contributes to cardiac protection.
Direct vascular effects
Preclinical research suggests that GLP-1 receptors are expressed on endothelial cells and cardiomyocytes. Activation of these receptors may improve endothelial function, reduce oxidative stress and protect against ischaemic injury. While human evidence for these direct effects is still emerging, they represent a plausible mechanism for the cardiovascular benefits observed in clinical trials.
NICE approval for cardiovascular risk reduction
In April 2026, NICE published updated guidance approving Wegovy (semaglutide 2.4 mg) specifically for cardiovascular risk reduction in adults with overweight or obesity and established cardiovascular disease. This was a significant expansion beyond the existing weight management indication.
Who is now eligible
- Adults with a BMI of 27 or above
- Established cardiovascular disease (previous heart attack, stroke, or peripheral artery disease)
- As an add-on to optimised standard cardiovascular care (statins, antihypertensives, antiplatelet agents)
NICE estimated that this expanded indication could make approximately 1.2 million additional patients in England eligible for treatment. This represents a major shift in how obesity is managed in the context of cardiovascular disease within the NHS.
What this means for patients:
If you have a history of heart attack, stroke or peripheral artery disease and are living with overweight or obesity, speak to your GP or cardiologist about whether semaglutide may be appropriate alongside your existing medications. You may now be eligible for NHS-funded treatment through specialist weight management services.
GLP-1 and heart failure
Heart failure is a growing public health concern, and obesity is a significant contributor, particularly to heart failure with preserved ejection fraction (HFpEF). The SELECT trial showed an 18 per cent reduction in heart failure events with semaglutide.
Additional data from the STEP-HFpEF trial demonstrated that semaglutide improved symptoms, exercise capacity and quality of life in patients with obesity-related HFpEF. These findings have led to growing interest in GLP-1 agonists as part of the heart failure treatment toolkit.
However, semaglutide is not currently licensed for heart failure in the UK. Its use in this context remains off-label and should only be considered under specialist supervision.
What about tirzepatide and cardiovascular outcomes?
Tirzepatide (Mounjaro) is a dual GLP-1/GIP receptor agonist that has shown impressive weight loss results and favourable effects on cardiovascular risk factors including blood pressure, lipids and glycaemic control. However, it does not yet have dedicated cardiovascular outcomes data.
The SURPASS-CVOT trial is currently evaluating the cardiovascular effects of tirzepatide in patients with type 2 diabetes and established cardiovascular disease. Results are expected in late 2026 or 2027. Until these data are available, tirzepatide cannot be recommended specifically for cardiovascular risk reduction.
Limitations and considerations
While the SELECT trial results are compelling, several important caveats should be noted.
- Specific population: SELECT enrolled patients with established cardiovascular disease. The results cannot be directly extrapolated to people without existing heart disease.
- No diabetes: Participants did not have diabetes. Those with type 2 diabetes were studied in separate trials (SUSTAIN-6 and PIONEER-6) with different designs.
- Duration: The mean follow-up was approximately 3.3 years. Very long-term cardiovascular effects beyond this period remain unknown.
- Cost and access: Expanded NHS access depends on commissioning decisions by local integrated care boards (ICBs). Availability may vary across regions.
- Complementary therapy: GLP-1 agonists are an addition to, not a replacement for, standard cardiovascular care including lifestyle modifications, statins, antihypertensives and antiplatelet therapies.
Important: Never stop or reduce existing heart medications without consulting your doctor. GLP-1 therapies are intended to be used alongside your current treatment, not as a substitute.
Other cardiovascular benefits of weight loss
Beyond the direct pharmacological effects of GLP-1 medications, the weight loss they produce brings additional cardiovascular benefits. Losing 5 to 10 per cent of body weight has been associated with:
- Reduced blood pressure (systolic and diastolic)
- Improved lipid profile (lower triglycerides, higher HDL)
- Reduced burden on the heart, particularly in heart failure
- Improved sleep apnoea, which itself is a cardiovascular risk factor
- Reduced left ventricular hypertrophy
- Improved endothelial function and arterial compliance
A comprehensive approach combining medication with dietary changes and regular physical activity maximises these benefits.