Abstract
PURPOSE: The optimal plasma lipoprotein(a) [Lp(a)] cutoff level for predicting atherosclerotic cardiovascular disease (ASCVD) in Southeast Asian populations remains limited. Therefore, our study aimed to identify the optimal plasma Lp(a) cutoff for predicting ASCVD in Thai patients. PATIENTS AND METHODS: We conducted a retrospective analysis of patients who underwent Lp(a) measurement at Siriraj Hospital between January 2019 and August 2024. Inclusion criteria included Thai ethnicity and age ≥15 years. Baseline characteristics, comorbidities, laboratory data, and Lp(a) levels were extracted from medical records. Lp(a) levels were compared between ASCVD and non-ASCVD groups. Odds ratios (OR) for ASCVD and coronary artery disease (CAD) were calculated using Lp(a)<25 nmol/L as the reference. RESULTS: A total of 2341 patients (age 54.4±17.7 years, 42.0% male) were included. Among them, 413 (17.6%) had ASCVD, 254 (10.9%) had CAD, 186 (7.9%) had ischemic stroke, 21 (0.9%) had peripheral arterial disease (PAD), and 14 (0.6%) had abdominal aortic aneurysm. Median Lp(a) levels (nmol/L) were significantly higher in patients with ASCVD [37.2 vs 24.4, p<0.001], CAD [43.8 vs 24.5, p<0.001], and AS [51.6 vs 25.3, p=0.002] compared to those without diseases. After adjusting for other risk factors, Lp(a)≥40 nmol/L was associated with increased risks of ASCVD [OR 1.538 (1.203-1.958)] and CAD [OR 1.877 (1.407-2.505)]. A multivariate model incorporating Lp(a)≥40 nmol/L with other risk factors demonstrated 70-80% sensitivity and specificity for predicting ASCVD and CAD. CONCLUSION: Elevated plasma Lp(a) levels are significantly associated with ASCVD and CAD. An Lp(a) cutoff of≥40 nmol/L predicted ASCVD and CAD risk in Thai.