Ethnic differences in glycated haemoglobin between white subjects and those of South Asian origin with normal glucose tolerance

Abstract

Objective: To determine whether ethnic differences exist in glycated haemoglobin between white subjects and those of South Asian origin with normal glucose tolerance (NGT) METHODS: Erythrocyte glycated haemoglobin (HbA(1c)) was compared between white subjects and those of South Asian origin with NGT defined by a 75 g oral glucose tolerance test (OGTT).

Results: 139 subjects with NGT comprising 36 people of South Asian origin (20 female) and 103 white subjects (49 female) were compared. Subjects of South Asian origin were younger (p<0.001) and weighed less (p<0.001) than white subjects. Fasting and 2 h capillary plasma glucose concentrations were similar in subjects of South Asian origin and white subjects, but HbA(1c) levels were higher (p<0.05) in subjects of South Asian origin (6.11+/-0.58%) compared with levels in white subjects (5.90+/-0.40%).

Conclusion: In subjects with similar fasting and postprandial glycaemia on OGTT, those of South Asian origin have higher HbA(1c) levels than white subjects. It is speculated that the higher glycaemia-independent HBA(1c) levels in people of South Asian origin could possibly contribute to their increase cardiovascular risk.