title: Association between bone turnover, micronutrient intake, and blood lead levels in pre- and postmenopausal women, NHANES 1999-2002.
abstract: BACKGROUND
  Blood lead levels (BLLs) have been shown to increase during periods of high bone turnover such as pregnancy and menopause.
  
  
  OBJECTIVE
  We examined the associations between bone turnover and micronutrient intake with BLLs in women 20-85 years of age (n = 2,671) participating in the National Health and Nutrition Examination Survey, 1999-2002.
  
  
  METHODS
  Serum bone-specific alkaline phosphatase (BAP) and urinary cross-linked N-telopeptides (NTx) were measured as markers of bone formation and resorption, respectively. Lead was quantified in whole blood. The association between tertiles of BAP and NTx, and BLLs was examined using linear regression with natural log transformed BLLs as the dependent variable and interpreted as the percent difference in geometric mean BLLs.
  
  
  RESULTS
  In adjusted analyses, mean BLLs among postmenopausal women in the upper tertiles of NTx and BAP were 34% [95% confidence interval (CI), 23%-45%] and 30% (95% CI, 17%-43%) higher than BLLs among women in the lowest tertiles of NTx and BAP, respectively. These associations were weaker, but remained statistically significant, among premenopausal women (NTx: 10%; 95% CI, 0.60%-19%; BAP: 14%; 95% CI, 6%-22%). Within tertiles of NTx and BAP, calcium intake above the Dietary Reference Intake (DRI), compared with below the DRI, was associated with lower mean BLLs among postmenopausal women but not premenopausal women, although most of the associations were not statistically significant. We observed similar associations for vitamin D supplement use.
  
  
  CONCLUSIONS
  Bone resorption and bone formation were associated with a significant increase in BLLs among pre- and postmenopausal women.
authors.affiliation: Department of Epidemiology and Biostatistics, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106-4945, USA. Leila.jackson@case.edu
authors.forename: Leila W
authors.initials: LW
authors.lastname: Jackson
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Cromer
authors.forename: Ashok
authors.initials: A
authors.lastname: Panneerselvamm
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000469:Alkaline Phosphatase / Q000097:blood; D015415:Biomarkers / Q000097:blood / Q000652:urine; D016723:Bone Remodeling / Q000187:drug effects* / Q000502:physiology; D002136:Calcium, Dietary / Q000008:administration & dosage; D024042:Collagen Type I / Q000652:urine; D003430:Cross-Sectional Studies; D004032:Diet / Q000706:statistics & numerical data; D019587:Dietary Supplements / Q000706:statistics & numerical data*; D004781:Environmental Exposure / Q000032:analysis / Q000706:statistics & numerical data; D004785:Environmental Pollutants / Q000097:blood* / Q000633:toxicity; D005260:Female; D006801:Humans; D019266:Iron, Dietary / Q000008:administration & dosage; D007854:Lead / Q000097:blood* / Q000633:toxicity; D016014:Linear Models; D008593:Menopause / Q000097:blood* / Q000502:physiology; D018977:Micronutrients / Q000008:administration & dosage*; D008875:Middle Aged; D009749:Nutrition Surveys; D010012:Osteogenesis / Q000187:drug effects; D010455:Peptides / Q000652:urine; D014807:Vitamin D / Q000008:administration & dosage; D055815:Young Adult
chemical_list: D015415:Biomarkers; D002136:Calcium, Dietary; D024042:Collagen Type I; D004785:Environmental Pollutants; D019266:Iron, Dietary; D018977:Micronutrients; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D014807:Vitamin D; D007854:Lead; D000469:Alkaline Phosphatase