Ethnic differences in insulin sensitivity and beta-cell function in premenopausal or early perimenopausal women without diabetes: the Study of Women's Health Across the Nation (SWAN).
OBJECTIVE
To assess differences in insulin sensitivity and beta-cell function between nondiabetic premenopausal or early perimenopausal non-Hispanic white women and African American, Chinese American, Japanese American, and non-Mexican-American Latino women.


METHODS
Homeostasis model assessments (HOMAs) of insulin sensitivity (HOMA%S) and beta-cell function (HOMA%beta) were used. Stepwise multivariable ethnic-specific ANCOVA models were used to compare HOMA%S and HOMA%beta between non-Hispanic whites and each of the four ethnic groups.


RESULTS
HOMA%S was lower in African Americans, Chinese Americans, and Japanese Americans when compared with non-Hispanic white women after correcting for waist circumference, presence of impaired fasting glucose, and site. Significant differences persisted only between African Americans and non-Hispanic whites after inclusion of triglycerides in the model. Triglycerides indirectly corrected for the differences in HOMA%S in the other two groups. There were no differences in HOMA%S between the non-Mexican-American Latinos and the non-Hispanic whites. Japanese Americans and Chinese Americans had lower HOMA%beta than non-Hispanic whites, whereas African Americans had higher HOMA%beta than non-Hispanic whites after correcting for confounders. HOMA%beta was similar between non-Mexican-American Latinos and non-Hispanic whites.


CONCLUSIONS
These data suggest that type 2 diabetes prevention strategies for African-American women should initially target decreased insulin sensitivity, whereas strategies for Japanese-American and Chinese-American women may initially need to target both decreased insulin sensitivity and beta-cell function. Previous studies of Mexican-American populations may not apply to non-Mexican-American Latino women.
Torréns
Javier I
JI
Department of Obstetrics Gynecology and Women's Health, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA. torrenji@umdnj.edu
Skurnick
Joan
J
Davidow
Amy L
AL
Korenman
Stanley G
SG
Santoro
Nanette
N
Soto-Greene
Maria
M
Lasser
Norman
N
Weiss
Gerson
G
D000328:Adult; D044383:Black People; D015992:Body Mass Index; D002681:China / Q000208:ethnology; D015331:Cohort Studies; D004032:Diet; D005006:Ethnicity; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D007328:Insulin / Q000097:blood* / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000378:metabolism*; D008593:Menopause / Q000502:physiology*; D008875:Middle Aged; D017697:Premenopause / Q000502:physiology*; D012016:Reference Values; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D014481:United States; D044465:White People; D001741:Black or African American
D007328:Insulin