Topical Area: Nutritional Epidemiology
Objectives : To estimate the annualized BMD changes of the lumbar spine and femoral neck by the use of calcium with or without vitamin D supplements in the Study of Women's Health Across the Nation (SWAN), a multi-center, multi-ethnic, community-based longitudinal cohort across the menopause transition.
Methods : Mixed model regression was used to estimate the 10 year annualized BMD change between the calcium with or without vitamin D supplements in SWAN women (n=1564; aged 42 to 52 years at baseline) unadjusted and adjusted for time-varying covariates (age, menopausal status[pre-, early peri-, late peri- and post- menopausal], smoking, physical activity) and time-constant covariates (height, baseline alcohol). Models were also stratified by menopausal status at baseline.
Results : When combined by menopausal status, calcium with or without vitamin D supplement use was associated with less femoral neck BMD annualized loss across in all models (beta = 0.0038 vs -0.0048; p=0.003). When stratified by pre- and peri- menopause at baseline, calcium with or without vitamin D supplement use was only significant in pre-menopausal women for both the lumbar spine (beta = 0.0067 vs -0.0082; p=0.02) and femoral neck (beta = -0.0037 vs -0.0052; p=0.002).
The use of calcium with or without vitamin D supplements is associated with less BMD loss ofthe lumbar spine and femoral neck, especially in premenopausal women.
Funding Sources : Funding for this study was provided through an unrestricted educational grant from Pfizer. The funding body had no influence on the study design; the collection, analysis, and interpretation of data; the writing of the report; and the decision to submit the paper for publication.