Familial hypercholesterolemia (FH) is a condition associated with significantly elevated low-density lipoprotein (LDL) cholesterol (LDL-C) or "bad cholesterol" and an increased risk of early onset of coronary artery disease if not sufficiently treated. Most commonly, individuals have heterozygous familial hypercholesterolemia (HeFH), caused by a single DNA variant (alteration) for FH that they have inherited from one (affected) parent. In rare cases, an individual can have homozygous familial hypercholesterolemia (HoFH), which is caused by having two causal FH DNA variants, where one variant is inherited from each (affected) parent. Individuals with HoFH typically have a more severe form of disease.
Having FH greatly increases the risk of hardening of the arteries (atherosclerosis), which can lead to heart attacks, strokes and other vascular conditions. Untreated individuals with FH have a 20-fold increased risk for coronary artery disease (CAD).
FH is treatable and the associated cardiovascular disease is largely preventable with early and intensive treatment, using statins, additional drugs, and other means. Other non-statin medications include PCSK9 inhibitors, ezetimibe, and bempedoic acid. These are effective treatments for individuals with FH who have a persistently elevated LDL-C despite treatment with maximally tolerated statin therapy.
Early identification and treatment of individuals with FH is key to preventing cardiovascular disease. Underdiagnosis of FH is a problem in most countries as high cholesterol can be an invisible and undetected problem until it leads to coronary artery disease.