Serum Lipoprotein(a) and Angiographic Severity of Coronary Artery Disease in Asian Indians

Abstract

Background: With the renewed interest in lipoprotein a (Lp(a)) shown by the European Atherosclerosis Society in relation to cardiovascular disease occurrence worldwide and especially in the South Asian population, its estimation once in a lifetime has been recommended (1–3). However, the role of this proatherogenic Lp(a) in regulating the severity of angiographic lesions in coronary artery disease (CAD) is poorly understood. This study aimed to correlate the serum Lp(a) level with angiographic lesion severity in subjects with CAD. Subjects and Methods: In this cross-sectional study, a total of 100 adult patients (mean age: 52.56 [±12.84] years, 84 [84%] males) with angiographically confirmed CAD were enrolled in a tertiary care hospital in Eastern India and their serum Lp(a) levels were estimated (by immunoassay method) and correlated with the SYNTAX score groups (<22, 22–33, and >33) and extent of disease – single-vessel disease (SVD), double-vessel disease (DVD), or triple-vessel disease (TVD). Results: Mean serum Lp(a) was elevated in the more severe disease group with SYNTAX >33 (88.79 mg/dl) than in lesser severity disease groups of SYNTAX 22-33 (57.07 mg/dl) and SYNTAX <22 (35.13 mg/dl), and this trend was found to be significant by analysis of variance (ANOVA) (P < 0.001). Mean levels of Lp(a) were lower in patients with SVD (33.15 mg/dl) and DVD (33.93 mg/dl) than in those with the TVD group (77.71 mg/dl), and this trend was found to be significant by ANOVA (P < 0.001). Conclusion: Serum Lp(a) values had a high significant positive correlation with the angiographic severity (higher SYNTAX score and Multivessel CAD) in patients of CAD in this study. Lp(a) is a known risk factor for CAD in South Asians and statins do not appear to decrease their levels; further, our study compounds the problem by correlating its level with increasing severity of CAD. This study therefore asserts the importance of the estimation of Lp(a) in South Asian individuals and proposes larger studies to confirm its correlation with the severity of CAD.