Effect of an increase in Lp(a) following statin therapy on cardiovascular prognosis in secondary prevention population of coronary artery disease

Oxidized phospholipids in cardiovascular disease

Prolonged or excessive exposure to oxidized phospholipids (OxPLs) generates chronic inflammation. OxPLs are present in atherosclerotic lesions and can be detected in plasma on apolipoprotein B (apoB)-containing lipoproteins. When initially conceptualized, OxPL-apoB measurement in plasma was expected to reflect the concentration of minimally oxidized LDL, but, surprisingly, it correlated more strongly with plasma lipoprotein(a) (Lp(a)) levels. Indeed, experimental and clinical studies show that Lp(a) particles carry the largest fraction of OxPLs among apoB-containing lipoproteins. Plasma OxPL-apoB levels provide diagnostic information on the presence and extent of atherosclerosis and improve the prognostication of peripheral artery disease and first and recurrent myocardial infarction and stroke. The addition of OxPL-apoB measurements to traditional cardiovascular risk factors improves risk reclassification, particularly in patients in intermediate risk categories, for whom improving decision-making is most impactful. Moreover, plasma OxPL-apoB levels predict cardiovascular events with similar or greater accuracy than plasma Lp(a) levels, probably because this measurement reflects both the genetics of elevated Lp(a) levels and the generalized or localized oxidation that modifies apoB-containing lipoproteins and leads to inflammation. Plasma OxPL-apoB levels are reduced by Lp(a)-lowering therapy with antisense oligonucleotides and by lipoprotein apheresis, niacin therapy and bariatric surgery. In this Review, we discuss the role of role OxPLs in the pathophysiology of atherosclerosis and Lp(a) atherogenicity, and the use of OxPL-apoB measurement for improving prognosis, risk reclassification and therapeutic interventions.

Effect of Different Types and Dosages of Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors on Lipoprotein(a) Levels: A Network Meta-analysis

ABSTRACT

Lipoprotein(a) [Lp(a)] has become an important component of the residual risk of cardiovascular diseases. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors display promising effects in controlling Lp(a) levels. However, the effects of different types and dosages of PCSK9 inhibitors on Lp(a) have not been studied in detail. These include 2 monoclonal antibodies, alirocumab and evolocumab, and inclisiran, a small interfering RNA. We searched PubMed, Web of Science, Embase, and Cochrane Library for randomized controlled trials to investigate the efficacy of PCSK9 inhibitors at the Lp(a) level. Although changes in Lp(a) levels were not the primary endpoint in any of these studies, they all described these valuable data. Forty-one randomized controlled trials with 17,601 participants were included, involving 23 unduplicated interventions. Most PCSK9 inhibitors significantly reduced Lp(a) levels compared with placebo. The pairwise comparison demonstrated no significant difference among most PCSK9 inhibitors. However, in the comparison among different dosages of alirocumab, the dosage of 150 mg Q2W showed a significant reduction in Lp(a) levels compared with the dosages of 150, 200, and 300 mg Q4W. In addition, the comparison results demonstrated the significant efficacy of evolocumab 140 mg Q2W compared with alirocumab at a dosage of 150 mg Q4W. The cumulative rank probabilities demonstrated that evolocumab 140 mg Q2W showed the highest efficacy. This study showed that PCSK9 inhibitors reduced Lp(a) levels by up to 25.1%. A biweekly dose of either 140 mg evolocumab or 150 mg alirocumab was the best treatment option. However, the reduction in Lp(a) levels with a single kind of PCSK9 inhibitor alone did not demonstrate sufficient clinical benefit. Therefore, for patients with very high Lp(a) levels who remain at high residual risk in the context of statin administration, it may be acceptable to use a kind of PCSK9 inhibitor, but the clinical benefit needs further investigation.