Dyslipidemia refers to abnormalities in lipoprotein metabolism that result in high total cholesterol, high LDL cholesterol, low HDL cholesterol, and high triglycerides. The prevalence of dyslipidemia varies but is estimated to affect over 100 million Americans. Dyslipidemia is caused by both genetic factors like familial hypercholesterolemia as well as secondary factors such as diabetes, hypothyroidism, and certain medications. It is a major risk factor for cardiovascular disease.

1. DYSLIPIDEMIA
Ahmed M. Rashad
PGY-1 Family Medicine

2. Objective
• Definition
• Prevalence
• Causes

3. Definition
Dyslipidemias are disorders of lipoprotein metabolism that
result in the following abnormalities:
• High total cholesterol (TC)
• High low-density lipoprotein cholesterol (LDL-C)
• Low high-density lipoprotein cholesterol (HDL-C)
• High triglycerides (TG)

4. Prevalence
• More than 100 million Americans, about one third of the
population have total cholesterol levels more than 200
mg/dL.
• Total cost associated with CVD and stroke in the US many
of which are related to dyslipidemia is estimated to be
more than $400 billion in 2006
• It is estimated that hyperlipidemia prevalence is around
25% in the state of Qatar
• American Heart Association. Cholesterol Statistics. Available at: www.americanheart.org/presenter.jhtml?
identifier=536. Accessed November 20, 2006
• High Cholesterol: Do you really understand it?. [Online]. 2010 Oct 5 [cited 2011 Sep 26]; Available
from: URL: http://www.thepeninsulaqatar.com/health/128194-high-cholesteroldo-you-really-
understand-it.html

5. Prevalence
The prevalence of dyslipidemia varies with the population
being studied. The prevalence is highest in patients with
premature coronary heart disease (CHD), which can be
defined as occurring before 55 to 60 years of age in men
and before 65 years in women. In this setting, the
prevalence of dyslipidemia is as high as 75 to 85 percent
compared to approximately 40 to 48 percent in age-
matched controls without CHD

6. Primary
Genetic Disorders
Secondary
Diabetes
Nephrotic Syndrome
Hypothyroidism
Drug – Induced
Hypertension
Causes

7. Familial Hypercholesterolemia
• Familial hypercholesterolemia (FH) is a genetically
modulated clinical syndrome in which the phenotype is
characterized by a high LDL-C level from birth, a
propensity to tendon xanthomata, and early onset CHD.
• Its established causes are LDLR mutations (most
common), gain-of-function PCSK9 mutations (<5 percent
of cases in most clinics), and familial defective apoB (<5
percent of cases), generally the apoB3500 mutation.

9. PRIMARY DYSLIPIDEMIA (Fredrickson’s
Classification)
Type Primary Lipid
Elevation
Lipoprotein Occurrence
I TG Chylomicrons Rare
IIa C LDL Common
IIb C, TG LDL, VLDL Most Common
III C, TG IDL Rare
IV TG VLDL Common
V TG VLDL,
Chylomicrons
Rare
Practical Therapeutics, AFP, 1998

12. Secondary Causes of Dyslipidemia
• Hypothyroidism
• Nephrotic syndrome
• Obstructive liver disease
• Diabetes mellitus
• Chronic renal insufficiency
• Cushing disease
• Drugs (oral contraceptives, diuretics)

15. References
• American Heart Association. Heart Disease and Stroke Statistics—2004 Update. Dallas, Tex:
American Heart Association; 2003.
• Grundy SM, Cleeman JI, Merz CN, Brewer HB Jr, Clark LT, Hunninghake DB, Pasternak RC, Smith
SC Jr, Stone NJ. Implications of recent clinical trials for the National Cholesterol Education Program
Adult Treatment Panel III guidelines. J Am Coll Cardiol. 2004; 44: 720–732. Abstract/FREE Full Text
• Fredrickson, DS; Lees, RS (1965). "A system for phenotyping hyperlipoproteinemia" (PDF).
Circulation 31 (3): 321–7. doi:10.1161/01.CIR.31.3.321. PMID 14262568.
• James, William D.; Berger, Timothy G.; et al. (2006). Andrews' Diseases of the Skin: clinical
Dermatology. Saunders Elsevier. ISBN 0-7216-2921-0.