Estrogen loss with reproductive aging in women is a major risk factor for osteoporosis in later life. Elderly women have elevated levels of undercarboxylated osteocalcin (ucOC), which indicates vitamin (vit) K inadequacy, and this has been associated with the risk of hip fracture. ucOC is also higher following the menopause when estrogen status has declined. In animal studies estrogen inhibits the development of vit K deficiency. Little is know about the role of estrogen in the regulation of bone vitamins in women. The purpose of this study is to determine if vit K status is compromised by declining estrogen status during the perimenopausal (PM) transition.
The aim will be to determine if estradiol (E2) levels are related to ucOC. Archived plasma samples from perimenopausal women (menstrual cycle day 6 of the follicular phase), aged 45 to 54, X BMI 24 plus/minus.6, who have low E2 (less than 35 pg/mL) or high E2 (greater than 70 pg/mL) will be examined for level of ucOC and total osteocalcin (OC). Univariate testing for differences between groups or ucOC as a percent of total OC, and independent factors (age, E2, estrone and follicle stimulating hormone) that predict ucOC as a percent of total OC will be examined. Confirming data would suggest vit K status may be compromised at midlife, rather than old age. Potentially, dietary vit K intake may need to increase above current guidelines for midlife women to protect bone health.

Agency
National Institute of Health (NIH)
Institute
National Institute of Nursing Research (NINR)
Type
Predoctoral Individual National Research Service Award (F31)
Project #
1F31NR007309-01A1
Application #
2711290
Study Section
National Institute of Nursing Research Initial Review Group (NRRC)
Program Officer
Phillips, Janice
Project Start
1999-02-27
Project End
Budget Start
1998-09-01
Budget End
1999-04-30
Support Year
1
Fiscal Year
1998
Total Cost
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Type
Schools of Nursing
DUNS #
791277940
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109