title: South Asians and coronary disease: is there discordance between effects on incidence and prognosis?
abstract: OBJECTIVE
  To determine whether the effect of South Asian ethnicity differs between studies of incidence and prognosis of coronary disease.
  
  
  METHODS
  Systematic literature review and meta-analysis, and cohort analysis from a national acute coronary syndrome (ACS) registry linked to mortality (National Institute of Cardiovascular Outcomes Research/Myocardial Infarction National Audit Project).
  
  
  METHODS
  International for the review, and England and Wales for the cohort analysis.
  
  
  METHODS
  The numbers of South Asians included in the meta-analysis were 111 555 (incidence) and 14 531 (prognosis) of whom 8251 were from the ACS cohort.
  
  
  METHODS
  Incidence studies: non-fatal myocardial infarction or fatal coronary heart disease; prognostic studies: mortality; HRs for 1-year all-cause death in ACS cohort.
  
  
  RESULTS
  South Asians had higher incidence of coronary disease compared with white subjects (HR 1.35 95% CI 1.30 to 1.40) based on meta-analysis of nine studies. Among 10 studies on prognosis, South Asians had better prognosis compared with white subjects (HR 0.78 95% CI 0.74 to 0.82). In the ACS cohort, the impact of diabetes (42.4% of South Asians, 16.9% of white subjects) on 1-year mortality was stronger in South Asians than white subjects (age-adjusted HR 1.83 95% CI 1.59 to 2.11 vs 1.53 95% CI 1.49 to 1.57). However, prognosis was better in South Asians even among diabetics, older people and those living in areas of the highest social deprivation.
  
  
  CONCLUSIONS
  South Asian ethnicity is associated with higher incidence of coronary disease, but lower mortality once coronary disease is manifest. The dissociation between effects on incidence and prognosis suggests that public health initiatives to reduce inequalities in mortality between South Asian and white populations should focus on primary prevention. This is a CALIBER study with ClinicalTrials.gov Identifier: NCT01163513.
authors: Department of Epidemiology and Public Health, University College London, 1-19 Torrington Place, London WC1E 6BT, UK. justin.zaman@nhs.net
authors: M Justin S
authors: MJ
authors: Zaman
authors: Pete
authors: P
authors: Philipson
authors: Ruoling
authors: R
authors: Chen
authors: Ahmed
authors: A
authors: Farag
authors: Martin
authors: M
authors: Shipley
authors: Michael G
authors: MG
authors: Marmot
authors: Adam D
authors: AD
authors: Timmis
authors: Harry
authors: H
authors: Hemingway
mesh_terms: D044466:Asian People; D003327:Coronary Disease / Q000208:ethnology*; D004739:England / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D011379:Prognosis; D012042:Registries; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D014852:Wales / Q000453:epidemiology; D044465:White People