FIRST MYOCARDIAL-INFARCTION IN PATIENTS OF INDIAN SUBCONTINENT AND EUROPEAN ORIGIN - COMPARISON OF RISK-FACTORS, MANAGEMENT, AND LONG-TERM OUTCOME

Objectives: To compare long term outcome after first myocardial infarc tion among British patients originating from the Indian subcontinent a nd from Europe Design: Matched pairs study Setting: Coronary care unit in central Leicester. Subjects: 238 pairs of patients admitted during 1987-93 matched for age (within 2 years), sex, date of admission (wit hin 3 months), type of infarction (Q/non-Q), and site of infarction. M ain outcome measures: Incidence of angina, reinfarction, or death duri ng follow up of 1-7 years. Results: Patients of Indian subcontinent or igin had a higher prevalence of diabetes (35% v 9% in patients of Euro pean origin, P<0.001), lower prevalence of smoking (39% v 63%, P < 0.0 01), longer median delay from symptom onset to admission (5 hours v 3 hows, P<0.01), and lower use of thrombolysis (50% v 66%, P<0.001). Dur ing long term follow up (median 39 months), mortality was higher in pa tients of Indian subcontinent origin (unadjusted hazard ratio=2.1, 95% confidence interval 1.3 to 5.4, P=0.002). After adjustment for smokin g, history of diabetes, and thrombolysis the estimated hazard ratio fe ll slightly to 2.0 (1.1 to 3.6, P=0.02). Patients of Indian subcontine nt origin had almost twice the incidence of angina (54% v 29%; P<0.001 ) and almost three times the risk of reinfarction during follow up (34 % v 12.5% at 3 pars, P<0.001). The unadjusted hazard ratio for reinfar ction in patients of Indian subcontinent origin was 2.8 (1.8 to 4.4, P <0.001). Adjustment for smoking, history of diabetes, and thrombolysis made little difference to die hazard ratio. Coronary angiography was performed with similar frequency in the two groups; triple vessel dise ase was the commonest finding in patients of Indian subcontinent origi n and single vessel disease the commonest in Europeans (P<0.001). Conc lusions: Patients of Indian subcontinent origin are at substantially h igher risk of mortality and of further coronary events than Europeans after first myocardial infarction. This is probably due to their highe r prevalence of diffuse coronary atheroma Their need for investigation with a view to coronary revascularisation is therefore greater Histor y of diabetes is an inadequate surrogate for ethnic origin as a progno stic indicator.