Is high HDL cholesterol always good?

Area of Science:

• Cardiovascular Medicine
• Pharmacology
• Biochemistry

Background:

• High-density lipoprotein (HDL) cholesterol inversely correlates with cardiovascular disease (CVD) risk.
• Residual CVD risk persists despite high-dose statin therapy, creating a need for novel treatments.
• Therapeutic strategies to increase HDL cholesterol are under investigation for CVD prevention.

Purpose of the Study:

• To evaluate the therapeutic benefit of increasing HDL cholesterol for cardiovascular disease.
• To assess the efficacy and safety of CETP inhibition as a strategy for HDL elevation.
• To explore the reasons behind the observed outcomes of HDL-raising therapies.

Main Methods:

• Review of existing studies on HDL-raising treatments, including nicotinic acid and CETP inhibitors.
• Analysis of clinical trial data, specifically focusing on torcetrapib's effects on cardiovascular risk.
• Discussion of potential mechanisms contributing to treatment outcomes.

Main Results:

• Nicotinic acid shows HDL-increasing effects, but direct evidence linking HDL elevation to reduced CVD is lacking.
• Torcetrapib, a CETP inhibitor, unexpectedly increased cardiovascular disease risk.
• The negative outcome of torcetrapib prompted debate on HDL-raising therapies and CETP inhibition.

Conclusions:

• The precise impact of therapeutically elevating HDL cholesterol, especially via CETP inhibition, on cardiovascular risk is not well understood.
• Potential explanations for torcetrapib's failure include off-target effects, dysfunctional HDL induction, or direct atherogenic impacts of CETP inhibition.
• Further interventional studies are necessary to clarify the role of HDL-raising therapies in managing cardiovascular risk.