Ethnic differences in the relationships between obesity and glucose-metabolic abnormalities: a cross-sectional population-based study.
OBJECTIVE
To evaluate whether body mass index (BMI) and other anthropometric indices of visceral obesity vary by ethnic group in their distribution and their relationship to metabolic abnormalities.


METHODS
Cross-sectional study.


METHODS
Canadian men and women, aged 35-75 years, of South Asian (n=342), Chinese (n=317), European (n=326) and Aboriginal (n=301) descent were recruited using stratified random sampling.


METHODS
Anthropometric indices (BMI, waist to hip ratio (WHR) and waist circumference (WC)), metabolic markers (fasting glucose, HbA1c, the ratio of total cholesterol/HDL) and clinical markers (systolic blood pressure) were assessed.


RESULTS
In subjects with BMI<30 kg/m2, the mean marker levels in people with elevated WC (>88 cm in women, >102 cm in men) vs people with normal WC were 6.16 vs 5.34 mmol/l for fasting glucose, 6.05 vs 5.66% for HbA1c and 5.46 vs 4.68 for the ratio of total cholesterol to HDL (P<0.001 in each case). At nearly every given level of BMI, non-European ethnic groups displayed significantly higher marker levels than Europeans. For example, for a given BMI, age and sex, the difference between European and non-European groups in HbA1c levels was 0.53% (95% confidence interval (CI): 0.37-0.69) for South Asians, 0.37% (95% CI: 0.2-0.54) for Chinese and 0.95% (95% CI: 0.78-1.12) for Aboriginal People.


CONCLUSIONS
Uniform cut-points for the classification of obesity using BMI, WHR or WC result in marked variation in the levels of glucose-metabolic abnormalities between ethnic groups. Existing action thresholds for these anthropometric indices do not apply to non-European ethnic groups and warrant revision.
Razak
F
F
Population Health Research Institute, McMaster University, Hamilton General Hospital, Hamilton, ON, Canada.
Anand
S
S
Vuksan
V
V
Davis
B
B
Jacobs
R
R
Teo
K K
KK
Yusuf
S
S
D000328:Adult; D000368:Aged; D001210:Asia, Southeastern / Q000208:ethnology; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000032:analysis / Q000378:metabolism*; D001794:Blood Pressure; D015992:Body Mass Index; D002170:Canada; D002681:China / Q000208:ethnology; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D003430:Cross-Sectional Studies; D005060:Europe / Q000208:ethnology; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007198:Indians, North American; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000208:ethnology* / Q000378:metabolism*; D012015:Reference Standards; D013599:Systole
D015415:Biomarkers; D001786:Blood Glucose; D002784:Cholesterol; D008076:Cholesterol, HDL; D006442:Glycated Hemoglobin