News · Heart & Metabolic
A statin alternative cut serious leg artery events by 36% in people who cannot take statins
Peripheral artery disease ends in amputation often enough that limb outcomes are the ones patients care about, and cholesterol trials rarely report them. This one did, in 1,624 patients who could not tolerate statins.
- Serious leg artery events fell by 36% on the drug.
- Counting repeat events as well as first ones, the reduction was 45%.
- Everyone in the group had peripheral artery disease and could not tolerate statins.
- Untreated, one in twelve had such an event over about three years.
- 1,624 patients within a larger randomized trial.
Cholesterol trials report heart attacks and strokes. Legs come further down the page, if they appear at all, which is a strange omission given what peripheral artery disease actually does to people.
The disease narrows the arteries supplying the legs. Early on it means pain when walking that eases on stopping. Later it means wounds that will not heal, and in the worst cases amputation. Patients rank losing a limb alongside the outcomes cardiologists spend their trials measuring.
Writing in Circulation, researchers went looking specifically at those outcomes. Among 1624 of the enrolled patients who had the disease at baseline, bempedoic acid reduced the risk of major adverse limb events by 36%.
What was being counted
Major adverse limb events are the serious end: sudden blockage of a leg artery, a procedure to reopen it, or amputation.
In the placebo group, 69 patients had one, which is 8.3% over a median of 40.6 months. Roughly one patient in twelve, across a little over three years, in a group receiving usual care.
Against that background, a 36% reduction in first events is a substantial claim.
The number that describes the disease better
There is a second figure that matters more than the headline, and it concerns what happens after the first event.
Peripheral artery disease is not a one-off. In the placebo group the rate of recurrent events ran at 4% a year, so patients who had one procedure frequently came back for another.
Counting every event rather than only the first, bempedoic acid reduced total major adverse limb events by 45%.
Standard trial reporting throws that information away. A patient who has three procedures counts once, identically to a patient who has one, and the difference between those two lives is exactly what the analysis of recurrent events recovers.
Who these patients are
Everyone in the trial was statin-intolerant, meaning they had stopped or could not take a statin, usually because of muscle pain.
That label deserves a caveat, because blinded trials have repeatedly shown that most muscle symptoms attributed to statins appear equally when patients unknowingly take placebo. The perception is not the drug in most cases.
It is also beside the point clinically. Whatever the mechanism, these are people not taking a statin, whose cholesterol goes untreated as a result, and who need something else. Bempedoic acid works on the same pathway one step earlier and is switched on only in the liver rather than in muscle, which is the design rationale for exactly this group.
Why the legs would respond
Peripheral arterial disease happens when plaque builds up in the arteries carrying blood to the limbs, and it is the same disease process that narrows the coronary arteries.
A drug that lowers LDL cholesterol slows plaque throughout the arterial tree, not selectively in the heart. That limb events fall alongside cardiac events is what the biology predicts, and the reason the finding is credible rather than surprising.
The caution that applies
This examines a subgroup within a larger trial. Subgroups are where spurious findings live, because a trial contains many of them and some will differ by chance.
Two things temper that here. The effect direction matches the drug’s known action, and the composite of cardiac and limb events moved consistently in patients with and without peripheral artery disease. A subgroup result that agrees with the main result and with the mechanism is a different animal from one that contradicts both.
The event counts are still modest, and the intervals around them correspondingly wide.
What it adds
Peripheral artery disease is undertreated relative to coronary disease, partly because its outcomes have been under-measured. Trials that do not count limb events cannot demonstrate benefit on them, and treatments then get justified on cardiac grounds to patients whose main fear is their legs.
This analysis counts them, in a group with no statin option, and finds a reduction in both the first event and the accumulated burden of repeat ones.
For someone who abandoned a statin years ago and has been living with claudication since, that is a reason to reopen the conversation.
People also ask
What did the analysis find?
Among 1,624 patients with peripheral artery disease at baseline, bempedoic acid reduced the risk of major adverse limb events by 36% (hazard ratio 0.64; 95% CI 0.44-0.93; P = 0.018) and total such events by 45% (relative risk 0.55; 0.35-0.85; P = 0.007). In the placebo group 69 patients (8.3%) had an event over a median 40.6 months.
What is a major adverse limb event?
The serious end of peripheral artery disease: acute blockage of a leg artery, surgery or stenting to restore blood flow, or amputation. These are the outcomes that change how a person lives.
What is bempedoic acid?
A cholesterol-lowering tablet that works on the same pathway as statins but one step earlier, and is activated only in the liver rather than in muscle. That is why it is used in people who cannot tolerate statins.
What does statin-intolerant mean?
Unable to take statins, usually because of muscle pain. It is a contested category, since blinded trials show much of the pain is not caused by the drug, and it nonetheless describes a large group of people not taking one.
Why does counting repeat events matter?
Because peripheral artery disease recurs. Counting only the first event discards everything that happens afterwards, and in the placebo group recurrent events ran at 4% a year. The larger reduction in total events reflects that burden.
Is this a subgroup analysis?
It examines patients with peripheral artery disease within a larger trial. Subgroup findings warrant more caution than the main result, though limb outcomes were a prespecified interest rather than something noticed afterwards.
Should a patient ask about it?
Anyone who has stopped a statin because of side effects is worth a conversation about alternatives, and that conversation belongs with a prescriber. This is general information rather than medical advice.