Hipercolesterolemia

Hypercholesterolemia

• Updated 2014 Aug 19 10:49:00 AM: review of low-density lipoprotein cholesterol (Lancet 2014 Aug 16) view updateShow more updates

Related Summaries:

• Familial hypercholesterolemia

• Dietary interventions for cardiovascular disease prevention

• Statins for prevention of cardiovascular disease

• Lipid-lowering pharmacotherapy overview

General Information

Description:

• condition characterized by elevated total cholesterol, low-density lipoprotein cholesterol or non-high-density lipoprotein cholesterol levels

• risk factor for cardiovascular disease

• this topic deals with nonfamilial forms of hypercholesterolemia; see also Familial hypercholesterolemia

Also called:

• hypercholesterolemia may also be called

o hypercholesterolaemia

o pure hypercholesterolemia

o Fredrickson Type IIa hyperlipoproteinemia

o hyperbetalipoproteinemia

o group A hyperlipidemia

o low-density lipoprotein hyperlipoproteinemia

• mixed hypercholesterolemia (hypercholesterolemia with hypertriglyceridemia) may also be called

o broad-betalipoproteinemia

o floating-betalipoproteinemia

o Fredrickson Type IIb hyperlipoproteinemia

o Fredrickson Type III hyperlipoproteinemia

o hypercholesterolemia with endogenous hyperglyceridemia

o hyperbetalipoproteinemia with prebetalipoproteinemia

o combined hyperlipidemia

Types:

•

Phenotype Lipoproteins(s) Elevated Serum Cholesterol Level Serum Triglyceride Level Atherogenicity

I Chylomicrons Normal to mildly increased Very severely increased None

IIa LDL Moderately increased Normal Severe

IIb LDL and VLDL Moderately increased Moderately increased Severe

III IDL Moderately increased Severely increased Severe

IV VLDL Normal to mildly increased Moderately increased Mild to Moderate

V VLDL and chylomicrons Normal to mildly increased Very severely increased Mild to Moderate

Abbreviations: HDL, high-density lipoprotein; IDL, intermediate-density lipoprotein; LDL, low-density lipoprotein; VLDL, very-low-density lipoprotein.

* HDL cholesterol levels not considered.

Reference - N Engl J Med 1967 Jan 5;276(1):34 full-text

Fredrickson Classification of Dyslipidemias*:

Epidemiology

Incidence/Prevalence:

• eleventh most common diagnosis made during family physician visits

o based on analysis of patient visits to family physicians in United States 1995-1998 in National Ambulatory Medical Care Survey

o hypercholesterolemia diagnosis coded in 2.8% of visits

o Reference - Ann Fam Med 2004 Sep-Oct;2(5):411 Texto completo de EBSCOhost full-text

• high cholesterol reported in 35% of adults having cholesterol screening in United States in 2009

o based on national survey data in United States

o Reference - MMWR Morb Mortal Wkly Rep 2012 Sep 7;61:697 Texto completo de EBSCOhost full-text

• 30-year risk for developing high low-density lipoprotein (LDL) cholesterol is 50% among United States adults

o based on cohort of 4,701 Framingham Offspring study participants

o estimated 30-year risks for various dyslipidemias

• > 80% for "borderline-high" LDL cholesterol (≥ 130 mg/dL [3.4 mmol/L])

• 50% for "high" LDL cholesterol (≥ 160 mg/dL [4.1 mmol/L])

• 25% women and 65% men for "low" high-density lipoprotein (HDL) cholesterol (< 40 mg/dL [1 mmol/L])

o Reference - Am J Med 2007 Jul;120(7):623

• 10% prevalence of elevated non-high-density lipoprotein (HDL) cholesterol in children aged 6-19 years in United States in 2007-2010

o based on cohort of 4,957 children aged 6-19 years from National Health and Nutrition Examination Survey (NHANES) during 2007-2010

o prevalence of serum lipids during 2007-2010

• elevated total cholesterol (≥ 200 mg/dL [5.2 mmol/L]) in 8.1%

• elevated non-HDL cholesterol (≥ 145 mg/dL [3.8 mmol/L]) in 10%

• low HDL cholesterol (< 40 mg/dL [1 mmol/L]) in 14.8%

o Reference - JAMA 2012 Aug 8;308(6):591, editorial can be found in JAMA 2012 Aug 8;308(6):621

• prevalence of elevated total and LDL cholesterol in children and adolescents may be as high as 10.7% depending on threshold used

o based on cohort of 9,868 children aged 6-17 years from National Health and Nutrition Examination Survey 1999-2006

o 10.7% prevalence of elevated total cholesterol (cut point 200 mg/dL or 5.2 mmol/L)

o 6.6% prevalence of elevated LDL cholesterol (cut point 130 mg/dL or 3.4 mmol/L) in 2,724 adolescents aged 12-17 years

o estimated that only 0.8% of adolescents exceed LDL threshold for considering for pharmacological treatment by current AAP guideline

o Reference - Circulation 2009 Mar 3;119(8):1108 full-text

Possible risk factors:

• spouse with hyperlipidemia associated with increased risk of hyperlipidemia

o based on cohort study

o 8,386 married couples aged 30-74 evaluated

o presence of spouse with hyperlipidemia had adjusted odds ratio 1.44 (95% CI 1.19-1.75)

o Reference - BMJ 2002 Sep 21;325(7365):636 full-text, commentary can be found in BMJ 2003 Feb 15;326(7385):396

Associated conditions:

• hypertriglyceridemia

• association with subclinical hypothyroidism controversial

o based on cohort studies

o hypercholesterolemia may be associated with subclinical hypothyroidism

• based on cohort of 1,191 patients aged 40-60 years

• 10.3% prevalence of subclinical hypothyroidism among patients with total cholesterol > 309 mg/dL (8 mmol/L)

• Reference - Clin Endocrinol (Oxf) 1999 Feb;50(2):217 Texto completo de EBSCOhost

o subclinical hypothyroidism may not be associated with abnormal lipid levels

• based on cohort of 8,218 adults > 40 years old in United States

• subclinical hypothyroidism not associated with abnormal lipid levels after adjusting for confounding factors

• Reference - Ann Fam Med 2004 Jul-Aug;2(4):351 Texto completo de EBSCOhost full-text

Etiology and Pathogenesis

Causes:

• contributions to elevated cholesterol levels may be

o genetic

o dietary

o metabolic (including medical conditions and drugs)

History and Physical

History:

Chief concern (CC):

• asymptomatic

Past medical history (PMH):

• ask about history

...