High levels of Lipoprotein(a), raise the risk of recurring coronary heart disease.

Increased levels of Lipoprotein(a),a variant of 'bad cholesterol', in the bloodstream are a risk factor for recurrent coronary heart disease (CHD) in people aged 60 or over, according to the results of a new study that tracked the issue over the course of 16 years.

The results, suggest that current cholesterol-lowering medications may not be effective at reducing the risk of recurrent CHD – such as a heart attack – due to elevated Lp(a).

While previous research has indicated that high levels of Lp(a) are also an important risk factor in the development of CHD, most of these studies have looked at Lp(a) levels and the risk of a first CHD event. The current study looked at whether elevated Lp(a) is predictive of a second or recurrent CHD event. It involved 607 Australians aged 60 years and over, all with prevalent CHD, who were followed for 16 years as part of the Dubbo study. There were 399 incident CHD cases.

The researchers found that:

The median Lp(a) in people who had a recurrent CHD event was 130 mg/L, compared to 105 mg/L in those who did not.

26% of people who had a recurrent CHD event – and 19% of those who did not – had Lp(a) levels of >300 mg/L.

18% of people who had a recurrent CHD event – and 8% of those who did not – had Lp(a) levels of >500 mg/L.

In senior citizens with prior CHD, elevated Lp(a) in the top 20% of the population distribution (>355 mg/L) predicted a 53% excess risk of a recurrent CHD event, compared with those in the lowest 20% of the population distribution (<50 mg/L) over 16 years of follow-up. This prediction was independent of other risk factors.

Refrence: Lipoprotein(a) and the risk of recurrent coronary heart disease: the Dubbo Study,Current Medical Research and Opinion, DOI 10.1080/03007995.2023.2214434