Elevated Lp(a) Linked to Repeat Heart Attacks and Stroke

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High levels of lipoprotein(a), or Lp(a), are a silent threat to heart health — and new research shows they may be just as dangerous for people already living with heart disease. A new study tracking patients over a decade found that the higher your Lp(a), the greater your risk of having another heart attack, stroke or cardiac procedure — even if you’re already on treatment. The risk rises steadily across all groups, and cholesterol-lowering drugs may help curb it.

What Elevated Lp(a) Levels Mean for Heart Health

Lp(a) is a type of cholesterol that increases the risk for heart problems. High levels of Lp(a) are known to raise the risk of having a first heart or stroke event — even in healthy people, no matter their sex or race. But until now, it wasn’t clear whether it also affects the risk of having another event after already being diagnosed with heart disease.

The study looked at this question using medical records from 2012 to 2022. Researchers analyzed data from 273,770 people who had a history of atherosclerotic cardiovascular disease (ASCVD) and had their Lp(a) levels measured in nanomoles per liter (nmol/L). The group included 43% women and 8% Black, 9% Hispanic and 59% White participants.

Tracking Heart Health Over Time

Researchers followed these patients for a median of 5.4 years. They tracked whether participants had another heart event, like a heart attack or stroke, or needed a heart procedure such as angioplasty or bypass surgery.

They found that Lp(a) levels were:

• Higher in women than in men
• Higher in Black patients than in Hispanic and White patients

Breakdown of Lp(a) Levels in the Group:

• 33% had low levels: under 15 nmol/L
• 33% had moderate levels: 15-79 nmol/L
• 15% had moderate to high levels: 80-179 nmol/L
• 10% had high levels: 180-299 nmol/L
• 5% had very high levels: 300 nmol/L or more

Risk Increases With Higher Lp(a)

During the study, 41,687 people (15%) had another heart event. The higher their Lp(a) levels, the more likely they were to have one.

Here’s how much the risk went up, compared with people who had very low Lp(a) (less than 15 nmol/L):

• 15-79 nmol/L: 4% higher risk
• 80-179 nmol/L: 15% higher risk
• 180-299 nmol/L: 29% higher risk
• 300 nmol/L or more: 45% higher risk

This pattern was the same across sex, race and ethnicity, type of heart disease, and whether the person had diabetes.

At the highest level (300 nmol/L or more), Black and Hispanic individuals had a slightly higher risk of another heart event than White individuals.

Possible Help From Cholesterol-Lowering Therapy

The study also found something hopeful: Powerful cholesterol-lowering treatments, such as PCSK9 inhibitors, may reduce the harmful effects of high Lp(a) — especially for people whose levels are 180 nmol/L or more.

Researchers checked for any major differences in how Lp(a) affected different groups. There were no strong differences by sex, race or ethnicity, heart disease history, or diabetes.

“The US has lagged behind many other countries in recommending that adults complete a simple blood test to measure Lp(a),” Katherine Wilemon, founder and chief executive officer of the Family Heart Foundation, said in a statement. “This study strongly confirms the importance of considering Lp(a) levels among other risk factors when determining an individual’s risk of future heart attacks and strokes.”