Familial hypercholesterolemia (FH) is an inherited cause of high LDL cholesterol and increased risk of early cardiovascular disease. It can be present in someone who feels well and follows a healthy lifestyle. Recognizing a possible inherited pattern helps organize both the person’s care and the family’s assessment. [1]
In this guide: What makes FH different from a single high cholesterol result? · A step-by-step assessment pathway · What can a genetic result add? · How does cascade screening work? · Why care is more than lifestyle advice · Reading an FH study: four questions · Prepare for your next appointment
What makes FH different from a single high cholesterol result?
LDL cholesterol is a laboratory measurement; FH is a clinical and sometimes molecular diagnosis. In FH, impaired handling of LDL can produce high levels from early life. LDLR, APOB and PCSK9 are important genes in dominant forms; rarer genetic mechanisms also exist. A high result can have other explanations, so the diagnosis requires context. [2]
Adults with LDL cholesterol above 190 mg/dL are among those who may need evaluation for FH, particularly with a family history of early heart disease. This is a clue rather than a stand-alone diagnosis. Children need age-appropriate assessment. Absence of visible cholesterol deposits does not exclude FH. [1]
A step-by-step assessment pathway
- Recover the lipid history. Bring results with dates and units, including measurements before medication if available. Mark when each treatment started; do not stop it to recreate an untreated measurement.
- Map the family pattern. Record who had high cholesterol, coronary disease or a heart attack, and their age at diagnosis. “Heart problems” is less informative than a documented event and age.
- Check alternative contributors. The clinician considers secondary causes of high cholesterol and interprets repeat measurements, examination and family history using an appropriate diagnostic framework.
- Discuss genetic testing. Ask what a positive, negative or uncertain result would change for you and your relatives.
- Make a follow-up plan. Identify the professional coordinating cholesterol management and family screening, and when results will be reviewed.
NICE recommends excluding secondary causes and using established diagnostic criteria; it also notes the importance of repeat LDL measurements because of biological and analytical variation. Local pathways and specialist judgment remain important. [3]
What can a genetic result add?
A clearly disease-causing finding can establish a molecular explanation and allow relatives to be tested for that specific change. A negative panel does not remove the need to manage high LDL or necessarily exclude a clinical FH diagnosis. A variant of uncertain significance is not equivalent to a confirmed molecular cause. [4] [5]
The companion LDLR gene guide explains how receptor biology and laboratory evidence are interpreted. Keep the questions separate: “Does this finding explain FH?” and “What treatment and monitoring does this person need?” A genetic explanation informs care but does not replace measurements, history and assessment.
How does cascade screening work?
Cascade screening means extending assessment through a family after an affected person is identified. When a familial pathogenic variant is known, targeted genetic testing can be combined with appropriate cholesterol assessment. In a typical dominant form, a person with one disease-causing variant has a 50% chance of transmitting it in each pregnancy. That is an inheritance probability, not a prediction that half the family will have a heart attack. [4]
Illustrative family exercise: write “confirmed FH,” “raised LDL without confirmed cause,” or “not yet assessed” beside each relative, without guessing from appearance or age. Then ask the clinical team whom to approach first and what information can be shared with consent. Our cascade testing guide explains the value of the original family report.
Why care is more than lifestyle advice
Healthy eating, physical activity and avoiding smoking support cardiovascular health, but lifestyle alone is often insufficient to control LDL in FH. Medicines are commonly needed, sometimes in combination. Decisions depend on age, LDL response, other risks, tolerability and the clinical situation. This guide does not choose a medicine or set an individual target. [1]
Some people have variants affecting both copies of an FH-associated gene or other severe genetic combinations. These can require particularly early specialist care. The terms heterozygous and homozygous describe genetic configurations; the actual presentation still needs careful assessment. [2]
Reading an FH study: four questions
- Who entered? Was FH genetically confirmed, diagnosed clinically or inferred from cholesterol alone?
- What was measured? Distinguish an LDL change from a cardiovascular event outcome.
- What was the comparison? Record background treatment and follow-up duration.
- Who was represented? Check ages, ancestry, severity and exclusions before generalizing.
Use the research search builder to explore an explicit question such as “familial hypercholesterolemia” and “cascade screening.” Save the search date and criteria. Our absolute and relative risk explainer helps distinguish impressive percentages from their practical meaning.
Prepare for your next appointment
Bring your lipid results, medicine list, family event ages and any genetic report. Ask: Is the diagnosis clinical, molecular or still under investigation? What is the follow-up target? Which relatives need assessment? How will uncertain findings be revisited? Use the care finder for genetics services and ask your usual clinician about a lipid specialist. The variant assistant can organize evidence questions; the disease finder connects related topics.
Does a healthy appearance rule out FH?
No. A person can feel well despite high LDL. Assessment relies on the appropriate clinical information, not appearance. [1]
Educational information. Do not change prescribed treatment on the basis of this article.