What are the key clinical features and family history indicators that suggest a diagnosis of familial hypercholesterolaemia (FH)?

Key clinical features that suggest a diagnosis of familial hypercholesterolaemia (FH) include:

• LDL‑C concentration greater than 13 mmol/l in adults or greater than 11 mmol/l in children and young people, which indicates a clinical diagnosis of homozygous FH ².
• Presence of tendon xanthomata, corneal arcus, or other physical signs, although their absence does not exclude FH ².

Family history indicators include:

• A family history of premature coronary heart disease (CHD) in first-degree relatives (before age 60) or in second-degree relatives (before age 50) ¹.
• A personal or family history of premature CHD, which is a key factor in suspecting FH ¹.
• Multiple family members with high cholesterol levels or early cardiovascular events ².