Dyslipidemia and Metabolic Syndrome Lecture Notes

A set of vocabulary flashcards covering the pathophysiology, classification, screening criteria, and pharmacological management of dyslipidemia and metabolic syndrome.

Dyslipidemia

A condition characterized by increased serum levels of total cholesterol ($TC$), increased $LDL-C$, or increased non-$HDL-C$.

$VLDL$ (Very-Low-Density Lipoprotein)

A lipoprotein that carries triglycerides to peripheral cells; high levels may be associated with increased $CHD$ risk.

$LDL$ (Low-Density Lipoprotein)

A lipoprotein that carries cholesterol to cells and is the primary target of cholesterol-reducing therapy; high levels are linked to increased $CHD$ risk.

$HDL$ (High-Density Lipoprotein)

A lipoprotein that removes cholesterol from cells; levels $> 60\,mg/dL$ are considered protective against $CHD$ while levels $< 40\,mg/dL$ increase risk.

Lipoprotein(a)

A complex of $LDL$ and apolipoprotein(a) that prevents $LDL$ from being taken up by the liver; elevated levels are an independent risk factor for premature $CHD$.

Triglycerides

A neutral fat stored in adipose cells that is positively correlated with the risk for $CHD$.

Familial Hypercholesterolemia Prevalence

An autosomal dominant ($AD$) condition occurring in approximately $1$ of every $200$ to $500$ persons in North America and Europe.

Friedewald Formula

The equation used to calculate $LDL$: $LDL = TC - (HDL + \frac{\text{triglycerides}}{5})$.

Borderline High Lipid Values ($mg/dl$)

Includes $LDL$ of $130-159$, $TC$ of $200-239$, and $TG$ of $150-200$.

Screening Ages for Healthy People

Routine screening is recommended for males $> 35$ years and females $> 45$ years.

$CHD$ Equivalents

Conditions treated with the same intensity as established coronary heart disease, including Diabetes mellitus, symptomatic carotid artery stenosis, peripheral arterial disease, and abdominal aortic aneurysm.

Major Risk Factors (other than $LDL$)

Cigarette smoking, Hypertension ($BP > 140/90\,mmHg$), low $HDL$, family history of premature $CHD$, and age (men $> 45$ years; women $> 55$ years).

Therapeutic Lifestyle Changes (Diet)

Reducing total fat to $20-30\%$ of total body fat, with saturated fat accounting for $< 7\%$ of calories.

Statins Mechanism

$HMG\,CoA$ reductase inhibitors that reduce $LDL$ and triglycerides while raising $HDL$; they act on cholesterol production.

Statin Contraindications

Absolute contraindications include acute or chronic liver disease; relative contraindications include use of cytochrome $p-450$ inhibitors.

High-intensity Statins

Statins that provide a $42-55\%$ reduction in $LDL$ cholesterol, such as Atorvastatin $20$, $40$, or $80\,mg$ per day, and Rosuvastatin $10$, $20$, or $40\,mg$ per day.

Bile Acid Sequestrants

A class of drugs including Cholestyramine that decreases $LDL$ but may cause $TG$ levels to rise.

Niacin (nicotinic acid)

The most effective drug in increasing $HDL$; it also decreases $LDL$ and $TGs$.

Fibrates

The most effective drug class in lowering $TG$, with Gemfibrozil being the most common example.

Hypertriglyceridemia Risk

When $TG \ge 500\,mg/dl$, the risk of acute pancreatitis is significantly increased, necessitating a very low-fat diet ($< 15\%$ of calories).

Metabolic Syndrome Criteria

Diagnosis requires 3 of the following: Central obesity, $TG \ge 150\,mg/dl$, low $HDL$, $BP \ge 130/85\,mmHg$, or fasting glucose $\ge 100\,mg/dl$.