Cadmium, follicle-stimulating hormone, and effects on bone in women age 42-60 years, NHANES III.
BACKGROUND
Increased body burden of environmental cadmium has been associated with greater risk of decreased bone mineral density (BMD) and osteoporosis in middle-aged and older women, and an inverse relationship has been reported between follicle-stimulating hormone (FSH) and BMD in middle-aged women; however, the relationships between cadmium and FSH are uncertain, and the associations of each with bone loss have not been analyzed in a single population.


OBJECTIVE
The objective of this study was to evaluate the associations between creatinine-adjusted urinary cadmium (UCd) and FSH levels, and the associations between UCd and FSH with BMD and osteoporosis, in postmenopausal and perimenopausal women aged 42-60 years.


METHODS
Data were obtained from the Third National Health Examination and Nutrition Survey, 1988-1994 (NHANES III). Outcomes evaluated were serum FSH levels, femoral bone mineral density measured by dual energy X-ray absorptiometry, and osteoporosis indicated by femoral BMD cutoffs based on the international standard. Urinary cadmium levels were analyzed for association with these outcomes, and FSH levels analyzed for association with bone effects, using multiple regression. Subset analysis was conducted by a dichotomous measure of body mass index (BMI) to proxy higher and lower adipose-synthesized estrogen effects.


RESULTS
UCd was associated with increased serum FSH in perimenopausal women with high BMI (n=642; beta=0.45; p< or =0.05; R(2)=0.35) and low BMI (n=408; beta=0.61; p< or =0.01; R(2)=0.34). Among perimenopausal women with high BMI, BMD was inversely related to UCd (beta=-0.04; p< or =0.05) and FSH (beta=-0.03; p< or =0.05). In postmenopausal women with low BMI, an incremental increase in FSH was associated with 2.78 greater odds for osteoporosis (109 with and 706 without) (OR=2.78; 95% CI=1.43, 5.42; p< or =0.01).


CONCLUSIONS
Long-term cadmium exposure at environmental levels is associated with increased serum FSH, and both FSH and UCd are associated with bone loss, in US women aged 42-60 years.
Gallagher
Carolyn M
CM
PhD Program in Population Health and Clinical Outcomes Research, Stony Brook University, Health Sciences Center L3-R071, Stony Brook, New York 11794-8338, USA. 2crgallagher@optonline.net
Moonga
Baljit S
BS
Kovach
John S
JS
D015502:Absorptiometry, Photon; D000328:Adult; D001822:Body Burden; D015992:Body Mass Index; D015519:Bone Density / Q000187:drug effects; D002104:Cadmium / Q000633:toxicity / Q000652:urine*; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D004785:Environmental Pollutants / Q000633:toxicity / Q000652:urine*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood*; D006306:Health Surveys; D006801:Humans; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000097:blood / Q000139:chemically induced* / Q000652:urine; D014481:United States
D004785:Environmental Pollutants; D002104:Cadmium; D005640:Follicle Stimulating Hormone; D003404:Creatinine