Objective: Vitamin D is essential for optimal bone health. However, vitamin D inadequacy may be overlooked by clinicians, thereby leading to inadequate vitamin D supplementation in patients with osteoporosis. This study evaluated serum 25(OH)D concentrations in postmenopausal women currently receiving antiresorptive or anabolic therapies for the treatment of osteoporosis, and determined factors related to 25(OH)D concentration. Methods: 1554 ambulatory, community-dwelling, postmenopausal women from 61 primary care physician practices in North America were recruited between November 2003 and March 2004. A serum 25(OH)D, intact parathyroid hormone (PTH), and chemistry panel were obtained. Information on factors that could influence vitamin D status was obtained by questionnaire. A multivariate logistic regression model was used to assess potential factors for suboptimal (<30 ng/mL) 25(OH)D concentrations. Results: 1536 subjects completed the study. The mean age was 71 years (range 47-103) and 92% were Caucasian. 35% of subjects resided at a latitude ³42°N (Boston, MA), while 24% resided below 35°N (Memphis, TN). The mean (SD) serum 25(OH)D was 30.4 (13.2) ng/mL. Serum 25(OH)D was <20 ng/mL in 18%, <25 ng/mL in 36%, and <30 ng/mL in 52% of subjects. Suboptimal 25(OH)D concentration was present in 63% of subjects receiving <400 IU of vitamin D daily compared with 45% receiving ³400 IU of vitamin D daily, p<0.0001. Factors related to vitamin D inadequacy (serum 25(OH)D <30 ng/mL) that remained significant in the multivariate analysis included: age >80 years, race (non-Caucasian), BMI >30 kg/m2, use of medications affecting vitamin D metabolism, supplementation of vitamin D <400 IU daily, lack of exercise, education level less than grade 12, and absence of previous physician counseling regarding vitamin D. Conclusions: More than half of North American women receiving osteoporosis treatment have vitamin D inadequacy. These results underscore a need for improved physician and public education regarding optimization of vitamin D status in the care of postmenopausal woman with osteoporosis.
Disclosure Information:
Faculty Member's Name: Ethel S. Siris, MD
Grants/Research Support: Merck & Co., Inc.
See more of Poster Abstracts: Osteoporosis - Epidemiology
See more of The Sixth International Symposium on Osteoporosis: Current Status and Future Directions