ConditionFH

Familial Hypercholesterolaemia

Inherited high cholesterol — common, dangerous, and usually undiagnosed

Last reviewed: July 2026
Version: 1.0
Review cadence: Annually

What it is

Familial hypercholesterolaemia is an inherited disorder — usually a mutation affecting the LDL receptor — that causes very high LDL cholesterol from birth. Because the exposure begins in childhood rather than midlife, arteries accumulate decades of damage before any symptom appears. The heterozygous form affects roughly 1 in 250 people, making it one of the most common serious genetic conditions there is.

Why it matters

This is the hole at the centre of cardiovascular prevention. FH causes heart attacks in people's forties and fifties — sometimes earlier — and it is highly treatable. Yet the great majority of people who have it do not know. It is also the condition that most sharply exposes a widespread misconception: that high cholesterol is a lifestyle failing. In FH it is not. Diet and exercise, while worth doing, will not fix it, and telling someone with FH to eat better instead of treating them is a serious error.

The evidence

What BioSignal knows about treating this

Guideline-anchored clinical contextLast reviewed July 2026 · reviewed annually · 3 references

What works for Familial Hypercholesterolaemia

BioSignal’s clinical summary, most important first.

High-intensity statin therapy — the foundation, often started young
Ezetimibe added where LDL targets are not met
PCSK9 inhibitors (evolocumab, alirocumab) or inclisiran — this is the population these drugs exist for
For homozygous FH: lomitapide, evinacumab, and lipoprotein apheresis
Cascade screening of relatives — finds the undiagnosed, which is most of them
Lifestyle measures — worthwhile, but they will NOT normalise LDL in FH

Signal Records relevant to this condition

Interventions and contributing factors — some of these records describe a cause rather than a cure. The rating shown is BioSignal’s confidence in that Signal Record, not a claim about how well it treats this condition. Open any of them for the full evidence.

Start Here

New to this? Read these first

Typical Journey

How this usually unfolds

Recognize risk factors
Get diagnosed
Track key biomarkers
Lifestyle first
Evidence-based treatment
Long-term monitoring

An orientation to how this topic is typically approached — not medical advice.

Who is at risk

It is inherited — a single altered gene copy is enough (autosomal dominant)
A first-degree relative with FH gives you a 50% chance of having it
Family history of premature heart attack (men under 55, women under 65)
Very high LDL from a young age, resistant to diet
Elevated lipoprotein(a) frequently coexists and compounds the risk

How it's diagnosed

FH is suspected from a very high LDL cholesterol (typically above ~4.9 mmol/L or 190 mg/dL in adults), a family history of premature coronary disease, and — occasionally — physical signs such as tendon xanthomas or corneal arcus at a young age. Formal criteria (Dutch Lipid Clinic Network, Simon Broome) combine these; genetic testing confirms it. CASCADE SCREENING of relatives is the single highest-yield action in the whole condition, and it is drastically underused: each diagnosed person has a 50% chance of a parent, sibling, or child carrying it too.

Lipid panel — LDL-C and ApoB
Lipoprotein(a) — frequently elevated alongside, and independently raises risk
Family history of premature cardiovascular disease
Clinical criteria (Dutch Lipid Clinic Network / Simon Broome)
Genetic testing (LDLR, APOB, PCSK9)
CASCADE SCREENING of first-degree relatives — the highest-yield step
Coronary artery calcium or imaging to refine risk in adults

Most important

Key biomarkers

LDL Cholesterol Apolipoprotein B Lipoprotein(a)Non-HDL Cholesterol Coronary Artery Calcium

Day to day

Lifestyle

Do not smoke — this matters enormously on top of inherited risk
Heart-healthy dietary pattern (helpful, but not curative in FH)
Regular exercise
Manage blood pressure and other risks aggressively

Explore

Explore this condition across BioSignal

Frequently asked questions

My cholesterol is very high but I eat well and exercise. How?

This is exactly the pattern that should raise the question of familial hypercholesterolaemia — and it is often met with disbelief or, worse, the implication that you must be lying about your diet. FH is genetic: your body clears LDL poorly, from birth, regardless of what you eat. Diet and exercise help a little and are worth doing, but they will not fix it. What fixes it is treatment. If your LDL is very high and there is early heart disease in your family, ask specifically about FH.

How common is it?

Roughly 1 in 250 people have the heterozygous form — far more common than most people assume, and comparable to type 1 diabetes. What is genuinely shocking is how few know: the overwhelming majority of people with FH are undiagnosed, and many find out only after a heart attack, or never.

If I have it, what about my family?

This is the most important question on this page. FH is autosomal dominant, so every first-degree relative — parents, siblings, children — has a 50% chance of having it. Cascade screening (testing relatives once one person is diagnosed) is the highest-yield thing in the entire condition, and it is drastically underused. A diagnosis in you is a chance to prevent heart attacks in people you love.

Do I really need a statin if I feel fine?

Yes — and 'feeling fine' is what FH does. The damage is silent and cumulative: your arteries have been exposed to high LDL since childhood, which is why untreated FH causes heart attacks decades early. Treatment started early is dramatically effective; treatment started after the first event is playing catch-up. This is one of the clearest cases in medicine for treating a number in someone who feels perfectly well.

Evidence summary

The causal relationship between lifetime LDL exposure and atherosclerotic cardiovascular disease is among the best-established in medicine, and FH is the clearest natural experiment demonstrating it. Statin therapy dramatically reduces cardiovascular events and mortality in FH, and earlier initiation confers greater benefit. Ezetimibe and PCSK9 inhibitors provide substantial additional LDL lowering. Cascade screening is cost-effective and strongly recommended by guidelines, yet the majority of people with FH remain undiagnosed worldwide.

References & sources

European Atherosclerosis Society consensus statements on familial hypercholesterolaemia
NICE guideline: Familial hypercholesterolaemia — identification and management
Statin outcome data in FH cohorts; PCSK9 inhibitor randomised trials

Educational information — not medical advice

Condition pages orient you across the evidence; they don't diagnose or treat. Diagnosis and management belong with a qualified clinician. See our Medical Disclaimer.

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