breastfeeding history, vitamin D-receptor genotype and risk of osteoporotic hip fracture among elderly women in Utah.
Document Type
Article
Journal/Book Title/Conference
Osteoporosis International
Volume
17(8)
Publication Date
2006
First Page
1146
Last Page
1153
Abstract
Introduction: The associations between vitamin D receptor (VDR) Bsm I and Fok I genotypes, parity, and risk of osteoporotic hip fracture were evaluated in a statewide population-based case-control study in Utah.
Methods: Women age 50-89 years with hip fracture (n=882) were ascertained via surveillance of 18 Utah hospitals from 1997 to 2001. Age-matched controls were randomly selected (n=897). Participants were interviewed in their homes, and blood samples were collected for genotyping.
Results: In logistic regression analyses that controlled for multiple confounders, Bsm I VDR genotype but not Fok I genotype was associated with risk of osteoporotic hip fracture (OR bb vs. BB genotype: 0.68; 95% CI: 0.50, 0.95). In similar analyses, no overall association was observed between parity status and risk of osteoporotic hip fracture. However, the effect of VDR genotype was modified by parity status. Among nulliparous women (n=140), Bsm I genotype was not associated with risk of hip fracture (OR bb vs. BB: 0.82; 95% CI: 0.28, 2.4); among primiparous women (n=133), bb genotype was associated with increased risk of hip fracture (OR bb vs. BB: 3.30; 95% CI: 0.96, 11.29); among multiparous women (n=1,400), bb genotype was associated with decreased risk of hip fracture (OR bb vs. BB: 0.59; 95% CI: 0.42, 0.84).
Conclusion: VDR Bsm I genotype was associated with risk of hip fracture in Utah women, and this effect was modified by parity status. Hormonal or lifestyle factors related to parity may underlie this interaction.
Recommended Citation
Wengreen HJ^, Munger RG, Cutler DR, Willing M. Parity, breastfeeding history, vitamin D receptor genotype and risk of osteoporotic hip fracture among elderly women in Utah. Osteoporosis International. 2006;17(8):1146-53.