What is the classification of hyperlipidemias (elevated levels of lipids in the blood)?

From the Guidelines

Hyperlipidemias are classified into two main categories of hypertriglyceridemia: moderate hypertriglyceridemia (fasting or nonfasting triglycerides 175-499 mg/dL) and severe hypertriglyceridemia (fasting triglycerides ≥500 mg/dL), with further classification based on lipoprotein patterns, such as elevated LDL, VLDL, or chylomicrons. The classification of hyperlipidemias is crucial for guiding treatment approaches and reducing the risk of cardiovascular disease. According to the most recent guidelines, including the 2021 guideline for the prevention of stroke in patients with stroke and transient ischemic attack 1, hypertriglyceridemia can be categorized into moderate and severe types. The Fredrickson classification system divides hyperlipidemias into six types (I through V) based on lipoprotein patterns, including:

• Type I: elevated chylomicrons
• Type IIa: increased LDL
• Type IIb: elevated LDL and VLDL
• Type III: IDL accumulation
• Type IV: increased VLDL
• Type V: elevated chylomicrons and VLDL Clinically, hyperlipidemias are more commonly classified as hypercholesterolemia (elevated LDL cholesterol), hypertriglyceridemia (elevated triglycerides), or mixed hyperlipidemia (both elevated), as noted in the 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA guideline on the management of blood cholesterol 1. This classification system helps guide treatment approaches, with statins typically used for hypercholesterolemia, fibrates or omega-3 fatty acids for hypertriglyceridemia, and combination therapy for mixed disorders, all tailored to the specific lipid abnormality and cardiovascular risk profile. It is essential to note that reducing triglyceride levels, especially in patients with severe hypertriglyceridemia, is crucial for reducing the risk of acute pancreatitis and cardiovascular disease, as highlighted in the 2021 guideline 1. In patients with ASCVD receiving recommended statin therapy, residual cardiovascular risk is present, and elevated triglycerides are associated with such risk, emphasizing the importance of classifying and managing hyperlipidemias effectively.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Classification of Hyperlipidemias

The classification of hyperlipidemias can be broken down into several categories, including:

• Pure or essential hypercholesterolemia 2
• Mixed or combined hyperlipidemias 2
• Major hyperglyceridemia, which can be either exogenous or endogenous 2
• Type II (hyperbetalipoproteinemia), Type III ("broad beta" or "floating beta" disease), and Type IV (hyperprebetalipoproteinemia or endogenous hypertriglyceridemia) 3
• Familial combined hyperlipidaemia, autosomal recessive remnant hyperlipidaemia, and familial chylomicronaemia syndromes 4

Characteristics of Hyperlipidemias

Each type of hyperlipidemia has distinct clinical and laboratory characteristics, including:

• Elevated levels of low-density lipoprotein (LDL) cholesterol and lipoprotein(a) (Lp(a)) 5
• Increased triglycerides, which can be secondary to other causes or primary hypertriglyceridaemia syndromes 4
• Presence of xanthomas, such as tendinosum xanthoma with or without planar xanthomas, palm creases syndrome, tuberous or tubero eruptive xanthomas 2
• Cardiovascular complications, such as coronary artery disease and acute or subacute pancreatitis 2, 5

Diagnosis and Treatment

Diagnosis of hyperlipidemias involves:

• Measuring fasting levels of total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides 5
• Evaluating Lp(a) levels in instances of positive family history for cardiovascular disease and/or severe progress of cardiovascular disease or premature cardiovascular events 5
• Using additional assays such as apolipoprotein (apo)B100, apoE genotype, and next-generation sequencing for detailed diagnosis 4 Treatment options include:
• Diet measures and lifestyle modifications, such as weight reduction and increased physical activity 5, 4
• Lipid-lowering drug therapy, including statins, bile acid sequestrants, ezetimibe, fibrates, nicotinic acid, and omega-3-fatty acids 5, 6
• Novel medications, such as volanesorsen, evinacumab, and other antisense therapeutics, for orphan disease indications such as familial chylomicronaemia syndrome 4, 6