Although low-density lipoprotein cholesterol (LDL-C) is established as the primary cardiovascular disease (CVD) risk factor, some individuals with LDL-C within desirable limits still develop coronary artery disease (CAD). Lipoprotein(a) (Lp(a)) has emerged as a genetically determined independent risk factor for CVD. This study aims to investigate Lp(a) by determining its association with coronary artery stenosis severity, identifying its ethnic-specific genetic determinants and assessing its relationship with an energy-dense dietary pattern.

The PUTRA-CV study is a 3-year, multicentre, case-control observational study involving adult patients who have undergone coronary angiography. The primary outcome is the association between Lp(a) levels and the severity of angiographic CAD (assessed by Gensini or Syntax score). Secondary outcomes include the frequencies of Lp(a)-associated single nucleotide polymorphisms (SNPs) (rs10455872 and rs3798220) and the association between dietary patterns and Lp(a) levels. Lp(a) will be measured using a particle-enhanced immunoturbidimetric method, and SNPs will be genotyped using high-resolution melting. Dietary intake will be assessed using a validated semiquantitative food frequency questionnaire. Data will be analysed using SPSS. Descriptive statistics will be used to summarise population characteristics. Bivariate analyses will use chi-square (2), independent t-tests or Mann-Whitney U tests as appropriate. The independent association between Lp(a) and coronary artery stenosis severity will be determined using multivariable logistic regression, adjusting for confounders. Empirically driven dietary patterns will be derived using reduced rank regression, and their association with Lp(a) will be assessed. For genetic analysis, allele frequencies of the LPA SNPs rs10455872 and rs3798220 will be calculated and compared between cases and controls.

Ethical approval has been obtained from the ethics committees of the Ministry of Health Malaysia (NMRR ID-24-00877-2ID-IIR), Universiti Putra Malaysia (JKEUPM-2024–246), Universiti Teknologi MARA (REC/07/2024-OT/FB/2) and Universiti Malaya Medical Centre (MREC ID NO: 2 02 453–13692). The findings will be disseminated via peer-reviewed journals and conferences.