What role for lipoprotein(a) in clinical practice?

Lipoprotein(a) level predicts the development of nonalcoholic fatty liver disease in Korean adults: A retrospective longitudinal study

Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent condition in the general population. Although recent studies have demonstrated a link between NAFLD and lipoprotein(a), a low-density lipoprotein-like particle synthesized in the liver, its precise physiological role and mechanism of action remain unclear. This study aimed to investigate the relationship between lipoprotein(a) levels and development of NAFLD and hepatic fibrosis in Korean adults. A total of 1501 subjects who underwent abdominal ultrasonography at least twice as part of a health checkup program were enrolled. Biochemical and ultrasonography results were analyzed longitudinally, and the degree of hepatic fibrosis was calculated in subjects with NAFLD using serum biomarkers, such as fibrosis-4 (FIB-4). During the 3.36-year follow-up period, 352 patients (23.5%) were diagnosed with NAFLD. The subjects were categorized into 4 groups based on their lipoprotein(a) levels. Remarkably, the incidence of NAFLD decreased as the lipoprotein(a) levels increased. Following logistic regression analysis and adjustment for various risk factors, the odds ratio for the development of NAFLD was 0.625 (95% CI 0.440-0.888; P = .032) when comparing the highest to the lowest tertile of lipoprotein(a). However, no significant association was observed between the occurrence of hepatic fibrosis and lipoprotein(a) levels in subjects with NAFLD. Lipoprotein(a) levels have been identified as a significant predictor of NAFLD development. Additional large-scale studies with extended follow-up periods are required to better understand the effect of lipoprotein(a) on NAFLD and hepatic fibrosis.

Genetic and nutritional factors determining circulating levels of lipoprotein(a): results of the "Montignoso Study"

Increasing evidence shows an association between high lipoprotein(a) [Lp(a)] levels and atherothrombotic diseases. Lp(a) trait is largely controlled by kringle-IV type 2 (KIV-2) size polymorphism in LPA gene, encoding for apo(a). Environmental factors are considered to determinate minor phenotypic variability in Lp(a) levels. In the present study, we investigated the possible gene-environment interaction between KIV-2 polymorphism and Mediterranean diet adherence or fish weekly intake in determining Lp(a) levels. We evaluated Lp(a), KIV-2 polymorphism, fish intake and Mediterranean diet adherence in 452 subjects [median age (range) 66 (46-80)years] from Montignoso Heart and Lung Project (MEHLP) population. In subjects with high KIV-2 repeats number, influence of Mediterranean diet adherence in reducing Lp(a) levels was observed (p = 0.049). No significant difference in subjects with low KIV-2 repeats according to diet was found. Moreover, in high-KIV-2-repeat subjects, we observed a trend towards influence of fish intake on reducing Lp(a) levels (p = 0.186). At multivariate linear regression analysis, high adherence to Mediterranean diet remains a significant and independent determinant of lower Lp(a) levels (β = - 64.97, standard error = 26.55, p = 0.015). In conclusion, this study showed that only subjects with high KIV-2 repeats can take advantage to lower Lp(a) levels from correct nutritional habits and, in particular, from Mediterranean diet.

Lipoprotein(a) the Insurgent: A New Insight into the Structure, Function, Metabolism, Pathogenicity, and Medications Affecting Lipoprotein(a) Molecule

Lipoprotein(a) [Lp(a)], aka "Lp little a", was discovered in the 1960s in the lab of the Norwegian physician Kåre Berg. Since then, we have greatly improved our knowledge of lipids and cardiovascular disease (CVD). Lp(a) is an enigmatic class of lipoprotein that is exclusively formed in the liver and comprises two main components, a single copy of apolipoprotein (apo) B-100 (apo-B100) tethered to a single copy of a protein denoted as apolipoprotein(a) apo(a). Plasma levels of Lp(a) increase soon after birth to a steady concentration within a few months of life. In adults, Lp(a) levels range widely from <2 to 2500 mg/L. Evidence that elevated Lp(a) levels >300 mg/L contribute to CVD is significant. The improvement of isoform-independent assays, together with the insight from epidemiologic studies, meta-analyses, genome-wide association studies, and Mendelian randomization studies, has established Lp(a) as the single most common independent genetically inherited causal risk factor for CVD. This breakthrough elevated Lp(a) from a biomarker of atherosclerotic risk to a target of therapy. With the emergence of promising second-generation antisense therapy, we hope that we can answer the question of whether Lp(a) is ready for prime-time clinic use. In this review, we present an update on the metabolism, pathophysiology, and current/future medical interventions for high levels of Lp(a).