Insulin sensitivity differs among ethnic groups with a compensatory response in beta-cell function.
OBJECTIVE
A drastic difference is evident in the prevalence of type 2 diabetes among ethnic groups. We examined the role of beta-cell function and insulin sensitivity in this disparity among 4 ethnic groups.


METHODS
beta-Cell function and insulin sensitivity were assessed in 77 healthy glucose-tolerant subjects using a hyperglycemic clamp (18 Asian-Americans, 9 African-Americans, 34 Caucasians, and 16 Mexican-Americans).


RESULTS
A wide range of variation was evident in clinical features of the studied subjects. Insulin sensitivity index and the second-phase insulin response differed among the 4 groups (P = 0.0023 and P = 0.0082, respectively), whereas the first-phase insulin response was marginally different (P = 0.1090). Stepwise regression analysis revealed that ethnicity was an independent determinant for the insulin sensitivity index (P = 0.0014) after adjusting for sex, age, diastolic blood pressure, waist-to-hip ratio, and BMI. Also, a compensatory response of beta-cell function was observed among the ethnic groups.


CONCLUSIONS
In this study, we observed a drastic difference in insulin sensitivity among the different ethnic groups and observed that their beta-cell function compensates for the prevailing insulin sensitivity. The difference in the prevalence of abnormal glucose tolerance in different ethnic groups could be a result of differences in insulin sensitivity
Chiu
K C
KC
Department of Medicine, University of California, Los Angeles, School of Medicine, USA. kchiu@mednet.ucla.edu
Cohan
P
P
Lee
N P
NP
Chuang
L M
LM
D000328:Adult; D001741:Black or African American; D044466:Asian People; D044383:Black People; D001786:Blood Glucose / Q000378:metabolism*; D005006:Ethnicity; D005260:Female; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood / Q000378:metabolism* / Q000494:pharmacology; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000378:metabolism*; D015141:Los Angeles; D008297:Male; D017058:Mexican Americans; D008800:Mexico / Q000453:epidemiology; D044469:Racial Groups; D012044:Regression Analysis; D044465:White People
D001786:Blood Glucose; D007328:Insulin