Angiographic Characteristics and Associated Risk Factors of Premature Coronary Artery Disease among South Asians: A Systematic Review.

Individuals living in South Asia are known to have earlier onset of coronary artery disease (CAD) compared with individuals of other ethnicities. No clear population specific risk factors have been identified for premature CAD in South Asians and studies on angiographic characteristics and their relationship with risk factors are lacking. A systematic literature search was conducted across Pubmed/Medline, Embase, Scopus, CENTRAL, CINAHL, Global Index Medicus and ClinicalTrials.gov databases to retrieve studies related to angiographic characteristics and related risk factors for premature CAD in South Asians. Forty studies with a total of 18,863 patients were included. Sixteen studies divided patients into different age groups, and twenty-four studies included only 1 premature CAD group. There was significant discrepancy in the age cut-offs used to define premature CAD. A majority of studies indicated single vessel disease to be the most common pattern of vessel involvement in young South Asians and left anterior descending artery was the most commonly involved vessel, while older individuals had more multivessel disease than younger counterparts. Younger individuals had higher prevalence of risk factors, demonstrated across individual studies, such as tobacco use, family history, obesity and dyslipidemia; all nonspecific to South Asians. Current available literature does not identify any clear differences regarding angiographic characteristics or associated risk factors for premature CAD in South Asians compared with other ethnicities, however more research is needed using advanced coronary imaging modalities to describe the plaque characteristics. More research is also needed regarding gender differences and risk stratification tools in these patients.