The effect of estrogen use on levels of glucose and insulin and the risk of type 2 diabetes in american Indian postmenopausal women : the strong heart study.
OBJECTIVE
To examine the associations between estrogen use and levels of insulin and glucose as well as the effect of estrogen use on the risk of type 2 diabetes.


METHODS
This report is based on 857 women who were both nondiabetic and postmenopausal at the baseline examination (1989-1992) and who completed a second examination (1993-1995) an average of 4 years later. The participants were divided into three groups: never, past, and current users based on their baseline estrogen use status. ANCOVA was used to compare the insulin and glucose levels among estrogen use groups. Logistic regression was used to evaluate the association between estrogen use and the incidence of type 2 diabetes.


RESULTS
Postmenopausal estrogen use was associated with lower fasting glucose (0.2 mmol/l lower) but higher 2-h glucose levels (0.4 mmol/l higher) compared with never users. It was not significantly associated with the risk of type 2 diabetes compared with past and never users, based on American Diabetes Association or World Health Organization definitions of diabetes or on only a 2-h glucose level > or = 11.1 mmol/l. However, the risk of type 2 diabetes increased with increasing duration of estrogen use among current users, with an odds ratio of 1.10 per year of use (95% CI: 1.01-1.19).


CONCLUSIONS
The data suggest that estrogen use in American Indian postmenopausal women may relate to deterioration of glucose tolerance. Longer duration of estrogen use among current users may relate to an increased risk of type 2 diabetes.
Zhang
Ying
Y
Center for American Indian Health Research, University of Oklahoma Health Sciences Center (HSC), Oklahoma City, Oklahoma 73190, USA. ying-zhang4@ouhsc.edu
Howard
Barbara V
BV
Cowan
Linda D
LD
Yeh
Jeunliang
J
Schaefer
Carl F
CF
Wild
Robert A
RA
Wang
Wenyu
W
Lee
Elisa T
ET
D001786:Blood Glucose / Q000378:metabolism*; D001823:Body Composition; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000503:physiopathology; D015914:Estrogen Replacement Therapy; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007198:Indians, North American; D007328:Insulin / Q000097:blood*; D008137:Longitudinal Studies; D017698:Postmenopause; D012307:Risk Factors; D014481:United States
D001786:Blood Glucose; D007328:Insulin