Sex differences in the association of endogenous sex hormone levels and glucose tolerance status in older men and women.
OBJECTIVE
Some evidence suggests an inverse association between type 2 diabetes and androgens in men and a positive association between type 2 diabetes and androgens in women. The purpose of this community-based study was to evaluate sex differences in the association between endogenous total and bioavailable estrogen and testosterone levels and glucose tolerance status.


METHODS
We included in this study 775 men and 633 postmenopausal non-estrogen-using women, all > or =55 years of age (mean ages 72 and 75 years, respectively). A 75-g oral glucose tolerance test (OGTT) was administered to fasting subjects from 1984 to 1987, when sera were frozen for measurement of total and bioavailable hormone levels. Total testosterone and estradiol levels were measured by radioimmunoassay, and bioavailable hormone levels were determined using a modified ammonium-sulfate precipitation method. The association between steroid hormones and glucose tolerance status was tested.


RESULTS
In sex-specific age- and BMI-adjusted analyses, men with impaired glucose tolerance (IGT) had significantly lower total testosterone levels. Women with IGT or type 2 diabetes had significantly higher bioavailable testosterone and total and bioavailable estradiol levels than those with normal glucose tolerance. Total testosterone and fasting plasma glucose were inversely associated in men (P = 0.0001), whereas bioavailable testosterone and estradiol were positively associated with fasting plasma glucose in women (P = 0.0001 and 0.001, respectively).


CONCLUSIONS
Additional studies are needed to further develop the hormone-diabetes connection.
Goodman-Gruen
D
D
Department of Family and Preventive Medicine, University of California at San Diego, La Jolla 92093-0631, USA. dgoodman@ucsd.edu
Barrett-Connor
E
E
D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism*; D015992:Body Mass Index; D002140:California; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D004958:Estradiol / Q000097:blood*; D005260:Female; D018149:Glucose Intolerance / Q000097:blood* / Q000503:physiopathology; D005951:Glucose Tolerance Test; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012727:Sex Characteristics; D013739:Testosterone / Q000097:blood*; D044465:White People
D001786:Blood Glucose; D013739:Testosterone; D004958:Estradiol