Is the higher risk of cardiovascular disease amongst South Asian populations linked to abnormalities of haemoglobin? A preliminary case control study.

The elevated burden of cardiovascular disease (CVD) amongst South Asian populations is a complex and multi-factorial phenomenon. South Asians evolved from environments where malaria was endemic, and while haemoglobin disorders frequent this group, a link to CVD has not been described. Using a case-control feasibility study, haemoglobin abnormalities identified by mass spectrometry were compared between South Asian patients with CVD (n = 72) and non-CVD controls (n = 84). Carotid-artery intima media thickness (CIMT) was used as a marker of vascular damage. Ultracentrifugation was used to separate lipoprotein subfractions, which were analysed for iron. Haemoglobin anomalies were more frequent for CVD patients than controls (34.7% vs. 14.3%, P < 0.001), as were subfractionated lipoprotein concentrations of iron (P < 0.001). Patients with haemoglobin disorders had greater CIMT (0.75 vs. 0.65 mm, P = 0.008), and lower HDL cholesterol (0.78 vs. 1.03 mmol/l, P = 0.003). These preliminary data suggest that haemoglobin disorders contribute to atherosclerotic disease in South Asians and further research is warranted.