Body mass index in mid-life women: relative influence of menopause, hormone use, and ethnicity.
OBJECTIVE
To assess the relative influence of menopausal status and hormone use on body mass index (BMI) among a multiethnic sample of mid-life women.


METHODS
Cross-sectional telephone survey conducted at seven sites where each site targeted an ethnic minority group and Caucasians as part of Study of Women's Health Across the Nation (SWAN).


METHODS
A total of 7181 Caucasians, 3949 African-Americans, 1660 Hispanics, 562 Chinese Americans, and 803 Japanese Americans between ages of 40 and 55 y residing in or near Boston, Chicago, Detroit, Los Angeles, Newark, NJ, Oakland, CA, and Pittsburgh, PA.


METHODS
Self-reported BMI based on weight in kg divided by height in m(2) menopausal status, physical inactivity, postmenopausal hormone use, ethnicity, and age in years.


RESULTS
Compared to premenopausal women (covariate adjusted M=27.3), women reporting a surgical menopause (M=28.2) or being in the perimenopausal transition (M=27.7 for early and 27.9 for late perimenopause) had higher BMI. Women reporting a natural menopause (M=27.4) did not have a higher BMI than premenopausal women, after adjusting for chronological age and other covariates. Hormone use was associated with lower BMI (M=26.5 vs 27.3). A comparison of effect sizes showed that menopausal status (F=13.1), followed by chronological age (F=24.0), were the least powerful predictors of BMI, whereas the more powerful predictors were physical activity level (F=1377.1) and ethnicity (F=400.5).


CONCLUSIONS
The menopausal transition affects body mass index in mid-life, but the effect is small relative to other influences. Interventions to increase physical activity are highly recommended to prevent increases in adiposity common in mid-life.
Matthews
K A
KA
School of Medicine, University of Pittsburgh, 3811 O'Hara Street, Pittsburgh, PA 15213, USA.
Abrams
B
B
Crawford
S
S
Miles
T
T
Neer
R
R
Powell
L H
LH
Wesley
D
D
D000328:Adult; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D003625:Data Collection; D005006:Ethnicity / Q000706:statistics & numerical data*; D015444:Exercise; D005260:Female; D020249:Hormone Replacement Therapy; D006801:Humans; D008593:Menopause; D008875:Middle Aged; D009765:Obesity / Q000209:etiology*; D013689:Telephone; D015430:Weight Gain