Hypercholesterolemia

Hypercholesterolemia
Other namesHypercholesterolaemia, high cholesterol
A color photograph of two bags of thawed fresh frozen plasma: The bag on the left was obtained from a donor with hypercholesterolemia, and contains altered serum lipid levels, while the bag obtained from a normal donor contains regular serum lipid levels.
SpecialtyCardiology
ComplicationsAtherosclerosis, thrombosis, embolism, heart attack, stroke, coronary thrombosis, fat embolism, cardiovascular and coronary heart disease
CausesPoor diet, junk food, fast food, diabetes, alcoholism, monoclonal gammopathy, dialysis therapy, nephrotic syndrome, hypothyroidism, Cushing's syndrome, anorexia nervosa
Differential diagnosisHyperlipidemia, hypertriglyceridemia

Hypercholesterolemia, also called high cholesterol, is the presence of high levels of cholesterol in the blood.[1] It is a form of hyperlipidemia (high levels of lipids in the blood), hyperlipoproteinemia (high levels of lipoproteins in the blood), and dyslipidemia (any abnormalities of lipid and lipoprotein levels in the blood).[1]

Elevated levels of non-HDL cholesterol and LDL in the blood may be a consequence of diet, obesity, inherited (genetic) diseases (such as LDL receptor mutations in familial hypercholesterolemia), or the presence of other diseases such as type 2 diabetes and an underactive thyroid.[1]

Cholesterol is one of three major classes of lipids produced and used by all animal cells to form membranes. Plant cells manufacture phytosterols (similar to cholesterol), but in rather small quantities.[2] Cholesterol is the precursor of the steroid hormones and bile acids. Since cholesterol is insoluble in water, it is transported in the blood plasma within protein particles (lipoproteins). Lipoproteins are classified by their density: very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), low density lipoprotein (LDL) and high density lipoprotein (HDL).[3] All the lipoproteins carry cholesterol, but elevated levels of the lipoproteins other than HDL (termed non-HDL cholesterol), particularly LDL-cholesterol, are associated with an increased risk of atherosclerosis and coronary heart disease.[4] In contrast, higher levels of HDL cholesterol are protective.[5]

Avoiding trans fats and replacing saturated fats in adult diets with polyunsaturated fats are recommended dietary measures to reduce total blood cholesterol and LDL in adults.[6][7] In people with very high cholesterol (e.g., familial hypercholesterolemia), diet is often not sufficient to achieve the desired lowering of LDL, and lipid-lowering medications are usually required.[8] If necessary, other treatments such as LDL apheresis or even surgery (for particularly severe subtypes of familial hypercholesterolemia) are performed.[8] About 34 million adults in the United States have high blood cholesterol.[9]

  1. ^ a b c Durrington P (August 2003). "Dyslipidaemia". Lancet. 362 (9385): 717–731. doi:10.1016/S0140-6736(03)14234-1. PMID 12957096. S2CID 208792416.
  2. ^ Behrman EJ, Gopalan V (December 2005). "Cholesterol and Plants". Journal of Chemical Education. 82 (12): 1791. Bibcode:2005JChEd..82.1791B. doi:10.1021/ed082p1791. ISSN 0021-9584.
  3. ^ Biggerstaff KD, Wooten JS (December 2004). "Understanding lipoproteins as transporters of cholesterol and other lipids". Advances in Physiology Education. 28 (1–4): 105–106. doi:10.1152/advan.00048.2003. PMID 15319192. S2CID 30197456.
  4. ^ Carmena R, Duriez P, Fruchart JC (June 2004). "Atherogenic lipoprotein particles in atherosclerosis". Circulation. 109 (23 Suppl 1): III2–III7. doi:10.1161/01.CIR.0000131511.50734.44. PMID 15198959.
  5. ^ Kontush A, Chapman MJ (March 2006). "Antiatherogenic small, dense HDL--guardian angel of the arterial wall?". Nature Clinical Practice. Cardiovascular Medicine. 3 (3): 144–153. doi:10.1038/ncpcardio0500. PMID 16505860. S2CID 27738163.
  6. ^ "Healthy diet – Fact sheet N°394". World Health Organization. September 2015. Retrieved July 6, 2016.
  7. ^ Cite error: The named reference BMJ2015 was invoked but never defined (see the help page).
  8. ^ a b Ito MK, McGowan MP, Moriarty PM (June 2011). "Management of familial hypercholesterolemias in adult patients: recommendations from the National Lipid Association Expert Panel on Familial Hypercholesterolemia". Journal of Clinical Lipidology. 5 (3 Suppl): S38–S45. doi:10.1016/j.jacl.2011.04.001. PMID 21600528.
  9. ^ "Hypercholesterolemia". Genetics Home Reference. Retrieved 16 May 2016.