Treating high density lipoprotein cholesterol (HDL-C): quantity versus quality

Area of Science:

• Cardiovascular Medicine
• Lipid Metabolism
• Atherosclerosis Research

Background:

• Low-density lipoprotein (LDL) and high-density lipoprotein (HDL) are key factors in coronary heart disease (CHD).
• Statin therapy effectively lowers LDL-cholesterol (LDL-C) but leaves residual cardiovascular risk.
• Low HDL-cholesterol (HDL-C) levels are linked to increased cardiovascular risk, suggesting a potential therapeutic target.

Purpose of the Study:

• To explore the role of HDL-cholesterol (HDL-C) levels and function in residual cardiovascular risk.
• To investigate whether increasing HDL-C levels alone is sufficient to reduce cardiovascular risk.
• To evaluate the importance of HDL's functional properties in therapeutic strategies.

Main Methods:

• Review of clinical trials and epidemiological studies on LDL-C, HDL-C, and cardiovascular outcomes.
• Analysis of evidence regarding the relationship between HDL-C levels and cardiovascular risk.
• Examination of studies investigating HDL function in patients with coronary artery disease (CAD) and genetic studies.

Main Results:

• Despite statins' efficacy, residual cardiovascular risk persists, highlighting the need to address other factors like HDL-C.
• Epidemiological data show an inverse relationship between HDL-C levels and cardiovascular risk.
• Evidence suggests HDL's functional capacity, not just its level, is critical; impaired HDL function is observed even with normal HDL-C levels in CAD patients.

Conclusions:

• Increasing HDL-C levels may not be sufficient to mitigate residual cardiovascular risk.
• The functional properties of HDL particles appear to be more important than mere concentration.
• Future therapeutic strategies for cardiovascular disease should consider HDL's functionality to effectively reduce residual risk.