Changes over 14 years in androgenicity and body mass index in a biracial cohort of reproductive-age women.
BACKGROUND
Body mass index (BMI) is directly related to testosterone (total T and free T) and inversely to SHBG cross-sectionally, but little is known about how changes in body fat and androgen markers affect each other over time.


METHODS
Participants included 969 White and Black women from the Coronary Artery Risk Development in Young Adults (CARDIA) cohort, who were ages 18-30 at entry into the study and were pre- or perimenopausal 16 yr later at the time of the CARDIA Women's Study (CWS). Total T and SHBG were assayed from specimens drawn at the CWS examination and stored serum from the yr 2 and 10 CARDIA exams. Free T was calculated based on total T and SHBG. BMI and waist circumference were measured at yr 2, 10, and 16.


RESULTS
Despite clinically significant increases in BMI and waist circumference, total T and free T tended to decline, whereas SHBG remained relatively constant. BMI and waist circumference were directly correlated with free T and inversely correlated with SHBG in cross-sectional analyses. In longitudinal, multivariable analyses, an annualized increase in BMI was inversely related to a concurrent annualized decrease in SHBG (beta = -0.79 ng/dl, and se = 0.22 in Blacks; beta = -1.07 ng/dl; and se = 0.31 in Whites). However, early increases in BMI were not related to later decreases in SHBG.


CONCLUSIONS
Increases in adiposity are closely tied to decreases in SHBG, but changes in BMI and SHBG may occur concurrently rather than sequentially.
Sternfeld
Barbara
B
Division of Research, Kaiser Permanente, 2000 Broadway, Oakland, CA 94612, USA. bxs@dor.kaiser.org
Liu
Kiang
K
Quesenberry
Charles P
CP
Wang
Hua
H
Jiang
Sheng-Fang
SF
Daviglus
Martha
M
Fornage
Myriam
M
Lewis
Cora E
CE
Mahan
John
J
Schreiner
Pamela J
PJ
Schwartz
Stephen M
SM
Sidney
Stephen
S
Williams
O Dale
OD
Siscovick
David S
DS
D000293:Adolescent; D000328:Adult; D000375:Aging / Q000502:physiology*; D000728:Androgens / Q000097:blood*; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology; D001837:Body Weights and Measures; D015331:Cohort Studies; D005260:Female; D006801:Humans; D011446:Prospective Studies; D044469:Racial Groups; D012098:Reproduction / Q000502:physiology*; D013997:Time Factors; D014770:Virilism / Q000097:blood / Q000209:etiology
D000728:Androgens