Heart Health

GLP-1 for obesity alone

How strong is the cardiovascular evidence for someone like you? Neither — obesity alone

Frontierglp1-ascvd-noFewer than 5 people have reached this rule so far

Approved for weight; cardiovascular benefit not yet proven in this group

Clinical review

All reviewers

No clinician has signed off this rule yet. It reflects our reading of the guidelines cited below, which has not been independently checked.

What someone who reaches this rule is told

Word for word, as generated for the example person below. Figures in the text are theirs.

  • Approved for weight; cardiovascular benefit unproven in this group

    Your BMI is 36.2, which meets the treatment threshold for weight — but the cardiovascular evidence does not yet extend to someone in your situation.

    This is the honest boundary of what SELECT actually tested: semaglutide prevented heart attacks and strokes in people who already had cardiovascular disease. The equivalent trial in people with obesity alone, no diabetes and no established cardiovascular disease is running now — SURMOUNT-MMO, tirzepatide, about 15,000 people, expected to complete in 2027 — but it hasn't reported. These drugs are approved and effective for weight loss, and weight loss improves blood pressure, triglycerides and blood sugar — but that is a different finding from what SELECT measured and what SURMOUNT-MMO will: heart attacks and strokes themselves, not the numbers thought to predict them.

    Outcome-provenTested in randomised trials measuring heart attacks, strokes, or death, not a stand-in for them.· checked 2026-09-12

    SELECT trial — semaglutide 2.4 mg in overweight/obesity with established CVD, without diabetes · Approved for weight; cardiovascular benefit unproven in this group

  • Outcome-proven for diabetes prevention; blood pressure and lipid changes are surrogates

    What is proven, and it is real rather than a stand-in: at your BMI, this class roughly halves the chance of going on to develop type 2 diabetes.

    In SURMOUNT-1's prediabetes group, 1,032 adults with obesity or overweight who already had prediabetes, 1.3% of people on tirzepatide progressed to type 2 diabetes over 176 weeks, against 13.3% on placebo. That is a 94% relative reduction, and roughly one fewer diabetes diagnosis for every 9 people treated for three years. It is an outcome-proven claim in its own right, not a surrogate for one: a diabetes diagnosis is a real, diagnosed disease with its own consequences, not a stand-in for something else. It also matters here specifically because diabetes is treated elsewhere on this page as an independent driver of heart attack and stroke risk. Preventing it plausibly helps your heart too, through that route and possibly others, even though nobody has run the trial that would prove the heart-attack-and-stroke number directly. Blood pressure, cholesterol and blood sugar moved as well, by real and quantified amounts. The card below has the numbers, and the reason they still count as a different, weaker kind of evidence than the diabetes finding above.

    Outcome-provenTested in randomised trials measuring heart attacks, strokes, or death, not a stand-in for them.· Level A· checked 2026-09-12

    SURMOUNT-1 — tirzepatide and progression from prediabetes to type 2 diabetes · Outcome-proven for diabetes prevention; blood pressure and lipid changes are surrogates

  • Surrogate outcomes, quantified

    Blood pressure, cholesterol and blood sugar: the numbers, in full.

    Systolic blood pressure: about 4 to 5 mmHg lower than placebo across the STEP programme (STEP 5 alone: −5.7 mmHg on semaglutide against −1.6 on placebo, over two years). LDL cholesterol: about 5% lower than placebo. Triglycerides: about 17% lower than placebo. Blood sugar in people who started with prediabetes: 84% back to a normal range at 68 weeks on semaglutide, against 48% on placebo, in STEP 1. Each of these is a guideline-recognised risk factor in its own right elsewhere on this page: the blood pressure section treats a few mmHg as directly consequential, and the cholesterol section treats a 5% LDL change as worth having. Read here, not as proof this class prevents your next heart attack, but as a genuine, quantified answer to "what is it actually doing to my numbers while we wait for that trial."

    Surrogate endpointMeasured as a change in a scan or a lab value, not in events. Usually a smaller trial, and a step removed from what you care about.· Level A· checked 2026-09-12

    STEP programme — semaglutide 2.4 mg, blood pressure and metabolic effects · Surrogate outcomes, quantified

An example person who reaches it

Obesity without heart disease” — an illustrative profile, not a real user.

48-year-old manBP 124/78LDL 120BMI 3610-yr PREVENT-ASCVD 1.7%

Their path through weight and glp-1 medication

  1. BMI ≥27 kg/m², or type 2 diabetes?Yes
  2. How strong is the cardiovascular evidence for someone like you?Neither — obesity alone ← this rule
  3. Applies to anyone starting oneAlways

Where it sits

Asked after: BMI 27 or above, or type 2 diabetes

Sources

Cited by the recommendations above.

Being tested further

A trial that could change this, still running or reported too recently to be settled.

  • SURMOUNT-MMO In people with obesity but no diabetes and no established heart disease, does tirzepatide prevent heart attacks, strokes and heart failure — or only improve the numbers thought to predict them?

What we are least sure of here

  • Q13Should GLP-1 for obesity without established disease sit in the frontier column?

Review this rule

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Runs in lib/engine/glp1Pathway.ts as glp1-ascvd-no.