Lipoprotein a - Lp(a)

Abstract

Lp(a) is a genetically determined, heritable, independent and causal risk factor for ASCVD. About 1 in 5 people worldwide have elevated Lp(a) (>50 mg/dL or >125 nmol/L) whereas in Indians it is 25 %. Epidemiological, genome-wide association and mendelian randomization studies have demonstrated an association between elevated Lp(a) levels and increased incidence of myocardial infarction, aortic valve stenosis, ischemic stroke, heart failure, CV and all-cause mortality. The increased Lp(a)-mediated CV risk is mediated by pro-inflammatory, pro-thrombotic and pro-atherogenic processes, leading to progression of atherosclerosis and increased risk of thrombosis. Lp(a) level reaches peak by 5 years of age and remains stable over time. Levels are not much influenced by dietary and environmental factors but it can vary in certain clinical situations like thyroid diseases, chronic kidney disease, inflammation and sepsis. It should be measured at least once in life time. Cascade testing for high Lp(a) is recommended in the settings of FH, family history of (very) high Lp(a), and personal or family history of ASCVD. In the absence of specific Lp(a)-lowering therapies, comprehensive risk factor management is recommended as per guidelines for individuals with elevated Lp(a). PCSK9 inhibitors and Inclisiran reduce Lp(a) by 25%. Pelacarsen is an antisense oligonucleotide and is found to reduce Lp(a) by 80%. In a recent Indian study of 1,021 CAD patients, presence of elevated Lp(a) (>50 mg/dL) correlated with severe angiographic disease. 37% of ACS patients exhibited elevated Lp(a) and it was higher in young CAD patients with FH (43%).