Background Aggressive clinical and public health interventions have resulted in significant reduction in coronary artery disease (CAD) worldwide. However, South Asian Immigrants (SAIs) exhibit the higher prevalence of CAD and its risk factors as compared with other ethnic populations. The main objective of the current study is to assess the prevalence of metabolic syndrome (MS), its association with high density Lipoprotein (HDL) function, Apo lipoprotein A-I (Apo A-I) polymorphisms, and sub-clinical CAD using common carotid intima-media thickness (CCA-IMT) as a surrogate marker.

Methods Community-based cross-sectional study on SAIs aged 35–65 years was conducted. Sub-clinical CAD was measured using CCA-IMT. Dysfunctional/pro-inflammatory (Dys-HDL) was determined using novel cell free assay and HDL inflammatory index.

Results According to the International Diabetes Federation definition, MS prevalence was 29.7% in SAIs without CAD. 26% had HDL inflammatory index ≥1 suggesting Dys-HDL. Six novel APOA-1 gene polymorphisms were discovered and on logistic regression, three single nucleotide peptides-SNPs (G2, G3, and G5) were found to be significantly associated with MS (p=0.397, p=0.386, p=0.054). On multi-variate analysis, MS was significantly associated with BMI >23 (p=0.005), Apo-A-I levels (p=0.01), and Lp [a] (p<0.0001).

Conclusion SAIs are known to be at a disproportionately high risk for CAD that may be attributed to a high burden for MS. There is need to explore and understand non-traditional risk factors with special focus to Dys-HDL, knowing that SAIs have low HDL levels. Large prospective studies are needed to further strengthen current study results.