Do reduced lipoprotein (a) levels lead to a reduction in heart events?

This study looked at the effect of alirocumab (Praluent) on lipoprotein (a) levels in patients at high risk of serious heart complications. They found that high lipoprotein (a) levels are associated with an increased risk of problems such as heart attack and stroke and lowering lipoprotein (a) levels by alirocumab treatment reduces this risk.

Lipoprotein (a) is a protein that forms part of cholesterol. Studies have shown that increased lipoprotein (a) levels are associated with a greater risk of heart attack or stroke. High cholesterol is treated with diet and with drugs called statins. When cholesterol remains high despite diet and statin use, an additional medication can be used. This second-line medication is called alirocumab.

Studies have shown that lowering lipoprotein (a) levels with alirocumab reduces the risk of a first heart attack or stroke. It is not clear if this also reduces the risk of further episodes or of other types of heart disease. 

This study involved 18,924 patients who had had a recent heart attack. All participants had high cholesterol levels not adequately controlled by statins. Half of these patients were treated with alirocumab, and half received a placebo. They were followed up for an average of 2.8 years to observe any episodes of heart or blood vessel disease, including heart attack, heart failure, stroke, and amputation. Lipoprotein (a) levels were also monitored.

Patients with the highest levels of lipoprotein (a) at the beginning of the study were 60% more likely to have a serious heart event than those with the lowest levels. Alirocumab led to decreased lipoprotein (a) and cholesterol levels. Those receiving alirocumab were 15% less likely to have a heart event than those receiving placebo. For each 5 mg reduction in lipoprotein (a) levels, the risk of having a heart event decreased by 2.5%.

This study showed that lowering lipoprotein (a) levels with alirocumab reduces the risk of major heart problems. 

This study was funded by the company that produces alirocumab.