Background: Globally Indian Asians have increased risk of coronary heart disease (CHD). Subclinical markers of atherosclerosis, such as carotid intima media thickness (CIMT) and coronary artery calcification scores (CACS), play an increasingly important role in risk prediction, but need to be validated in different ethnic groups.

Method: We studied 415 Indian Asian men and 485 European men in a population-based study in London. Prevalent CHD was identified from primary care medical records. CIMT (maximum) was measured in the far wall of the left common carotid artery using B mode ultrasound. CACS were measured using computed tomography.

Results: Participants were aged 70±6 years. Indian Asians had more CHD (38% vs 20%, p<0.001), diabetes (42% vs 17%, p<0.001) and hypertension (80% vs 62%, p<0.001). Despite this, there were no ethnic differences in CIMT and CAC scores. Geometric means (95%CI) for CIMT in Indian Asians and Europeans were 0.96 (0.94, 0.98) and 0.95(0.93, 0.97), p=0.56. Median CACS scores were 127 (IQR:17, 468) and 150 (30, 475) In Indian Asians and Europeans respectively(p=0.42). Associations between CIMT/CAC and CHD risk factors were similar in the two ethnic groups. CAC score >400AU was strongly associated with CHD in Europeans, but there was no association in IA (fully adjusted odds ratios: E: 2.21, p=0.026, IA: 1.12, p=0.75). CIMT was strongly and significantly associated with CHD in both ethnic groups (Figure).

Conclusion: CACS are a valid indicator of CHD in European but not in Indian Asian men. In contrast, CIMT is a valid surrogate in both ethnic groups.