Levels and changes of HDL cholesterol and apolipoprotein A-I in relation to risk of cardiovascular events among...

Area of Science:

• Cardiovascular Medicine
• Lipidology
• Pharmacotherapy

Background:

• Uncertainty exists regarding the association between HDL-C/apoA-I and cardiovascular risk in patients achieving very low LDL-C with statins.
• The impact of HDL-C or apoA-I level changes on cardiovascular risk after statin initiation is unknown.

Purpose of the Study:

• To investigate the association of HDL-C and apoA-I levels with cardiovascular risk in patients on statin therapy, particularly those with very low LDL-C.
• To determine if increases in HDL-C or apoA-I levels after statin initiation correlate with reduced cardiovascular risk.

Main Methods:

• A meta-analysis of 8 statin trials involving 38,153 participants was conducted.
• Individual patient data on lipids and apolipoproteins at baseline and 1-year follow-up were analyzed.
• Major cardiovascular events were tracked in relation to HDL-C and apoA-I levels and their changes.

Main Results:

• Both HDL-C and apoA-I levels were inversely associated with major cardiovascular events, persisting even at LDL-C levels below 50 mg/dL.
• An increase in apoA-I levels was associated with a reduced risk of cardiovascular events (HR, 0.93; 95% CI, 0.90-0.97).
• A rise in HDL-C levels did not show a significant association with reduced cardiovascular risk (HR, 0.98; 95% CI, 0.94-1.01).

Conclusions:

• HDL-C and apoA-I levels are strongly associated with reduced cardiovascular risk in statin-treated patients, irrespective of achieved LDL-C levels.
• Increased apoA-I concentration, but not HDL-C, is linked to a lower risk of major cardiovascular events.
• Therapies aimed at increasing apoA-I warrant further investigation for cardiovascular risk reduction.