The relationship between lipoprotein(a) and coronary artery disease, as well as its variable nature following myocardial infarction

Abstract

The present study aimed to investigate the relationship between the severity of coronary artery disease (CAD) and level of Lipoprotein (LP)(a). The study included 52 CAD patients and a control group consisting of 38 individuals. The patients were classified into three groups based on the clinical form of CAD (stable angina pectoris, SAP, unstable angina pectoris, UAP, and myocardial infarction,MI), and were further divided into three groups based on CAD severity (1-, 2- and 3-vessel). Serum Lp(a) levels were monitored 4, 8, and 24 h, 10 and 30 days following acute MI in 18 patients. Based on regression analysis, Lp(a) was not correlated with other lipoproteins or with risk factors of CAD, such as body mass index, smoking, family history, diabetes, age, gender, and hypertension (r = 0.08-0.22). 72% of the patients in the CAD group and 24% of the control group had an Lp(a) level > 30 mg dL(-1) (P = 0.004), and Lp(a) levels were higher in 3-vessel patients than in 2-vessel and 1-vessel CAD patients (86% vs. 68%, P = 0.02 and 86% vs. 62%, P=0.01, respectively). Serum Lp(a) levels were higher in the UAP and MI groups than in the SAP group (48 ± 44.7 mg dL(-1), 49 ± 36.1 mg dL(-1) and 31.2 ± 22.3 mg dL(-1), respectively, P=0.02). Lp(a) levels increased after acute MI, and reached peak levels 10 days post-MI (41% increase, P=0.001) and remained considerably elevated (18%) 30 days post-MI (P=0.01). Serum Lp(a) was higher in the UAP and MI patients in comparison with the SAP patients, and was higher in 3-vessel CAD in comparison with 1- and 2-vessel CAD patients.