Abstract 1197: Migration Related Differences in Blood Iron Availability Among Resident Compared With Migrant South Asians are Related to Indices of Atherogenesis

Abstract

Introduction. The global burden of coronary heart disease is estimated to be the highest on the Indian subcontinent. The pathophysiology of this increased risk is unclear, and its magnitude increases with migration from India to Britain. We sought to measure the impact of migration and nutritional transition on haematological parameters amongst South Asians, and their relation to indices of atherogenesis - oxidised low density lipoprotein (oxLDL) and paraoxonase activity (on HDL). Methods. We studied oxidised LDL and the antioxidant enzyme, paraoxonase (PON1), blood count profiles, dietary intake and iron biochemistry in 230 migrant Indian Gujaratis living in Britain, and 305 of their contemporaries (age and gender matched) still living in villages of origin in India. Results. Haemoglobin levels were associated with established CHD risk factors (including blood pressure, serum cholesterol, and 10 yr CHD risk score) irrespective of site and gender (P<0.001), and highest amongst migrants (P<0.001). Amongst women, migration related differences included a greater red blood cell volume in migrants, and was associated with greater levels of oxidised LDL compared to rural contemporaries (P<0.001). Metabolic and dietary indices of iron were associated with levels of haemoglobin and in turn with oxidised LDL (partial correlation coefficient = 0.18, p<0.001) and paraoxonase activity (0.28, p<0.001), adjusting for the effects of gender and site. Conclusion. Levels of haemoglobin are associated with CHD risk factors and direct indices of atherosclerosis in our culturally matched population of rural and migrant Indians. Accelerated erythropoiesis or higher iron levels may underline an increased susceptibility for the oxidative modification of LDL in this ethnic group.