HbA1c Levels in Families of Ethnic Minorities with Early Onset Type 2 Diabetes: Glycaemic Control and Ethnicity

Aims: Ethnic differences and factors associated with high glycated haemoglobin A1c (HbA1c) levels in families of East Indian and West African descents with early onset type 2 diabetes mellitus (T2DM) were compared. Glycaemic control is affected by genetics and is strongly influenced by adherence to medication and cultural adaptations to instructions.

Study Design: A 12 months study.

Place and Duration of Study: Diabetes Mellitus Clinic, University of the West Indies Hospital, Mona, Jamaica, between September 2000 to October 2003.

Methodology: A 12 months analysis was done on 54 members of families of East Indian descent and 48 members of families of West African descent with early onset T2DM enrolled in the Maturity Onset Diabetes of the Young (MODY) study. HbA1c levels were measured at baseline, 6 and 12 months.

Results: The families of West African descent started at baseline with significantly higher HbA1c (11.0±1.5% versus 10.0±1.5% [97±17 mmol/mol versus 86±16 mmol/mol], P=0.05) than families of East Indian descent. Nevertheless their mean HbA1c level was significantly lower at 12 months (7.0±0.7% versus 7.9±0.5% [53±7 mmol/l versus 63±5 mmol/mol], P=0.05). Variables such as access to healthcare, social status and education, age, body mass index (BMI), duration of diabetes and insulin and lipid therapies were similar in the ethnic groups. Lipid function was abnormal over 12 months in families of East Indian descent. Families of East Indian descent adhere less to medication guidelines and instructions.

Conclusion: Families of East Indian descent had poorer glycaemic control than those of West African descent. The poor control may be linked to genetics as seen in triglyceride and high density lipoprotein cholesterol profile over 12 months and may have been influenced by ethnic differences in adherence to medication and instruction following.