Insulin response in a triethnic population: effects of sex, ethnic origin, and body fat. Miami Community Health Study.
OBJECTIVE
To assess sex and ethnic differences in hyperinsulinemia/insulin resistance and to examine the impact of percent body fat on such differences.


METHODS
A cross-sectional epidemiological study was performed in a normoglycemic population of African-Americans (n = 159), Cuban Americans (n = 128), and non-Hispanic whites (n = 207) who resided in Dade County, Florida, from 1990 to 1995. The insulin area under the curve (AUC) in response to a standard 75-g oral glucose tolerance test (OGTT) was used as an indicator of hyperinsulinemia/insulin resistance. Analysis of covariance was performed to compare sex and ethnic differences in the insulin AUC. Multiple linear regression was used to evaluate the independent correlates of the insulin AUC.


RESULTS
After covariate adjustment for percent body fat, men displayed a significantly higher insulin AUC than did women (P < 0.001). African-Americans and Cuban-Americans each had a significantly higher insulin AUC than did non-Hispanic white participants (P = 0.01). Alcohol consumption was inversely related to AUC (P = 0.04).


CONCLUSIONS
Despite the greater percentage of body fat in women, the insulin AUC was similar in women and men. After adjustment for the sex difference in percent body fat, women displayed a lower insulin AUC than did men, indicating enhanced insulin sensitivity. These differences by sex and ethnicity in insulin resistance are consistent with established differences in heart-disease risk (i.e., higher in men and African-Americans) and suggest that hyperinsulinemia/insulin resistance may partly underlie such differences.
Donahue
R P
RP
University of Miami School of Medicine, Department of Epidemiology and Public Health, Florida, USA. rdonahue@ubmedf.buffalo.edu
Bean
J A
JA
Donahue
R A
RA
Goldberg
R B
RB
Prineas
R J
RJ
D000328:Adult; D044383:Black People; D001786:Blood Glucose / Q000032:analysis* / Q000378:metabolism; D001823:Body Composition; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003462:Cuba / Q000208:ethnology; D005260:Female; D005431:Florida; D005951:Glucose Tolerance Test; D006630:Hispanic or Latino; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood / Q000175:diagnosis* / Q000208:ethnology; D007328:Insulin / Q000097:blood* / Q000378:metabolism; D007333:Insulin Resistance / Q000502:physiology*; D016014:Linear Models; D008297:Male; D012737:Sex Factors; D044465:White People; D001741:Black or African American
D001786:Blood Glucose; D007328:Insulin