Malak El Sabeh1, Paola Ghanem1, Laila Al-Shaar1, Maya Rahme2, Rafic Baddoura3, Georges Halaby4, Ravinder J Singh5, Dirk Vanderschueren6,7, Roger Bouillon8, Ghada El-Hajj Fuleihan2. 1. Scholars in Health Research Program, Department of Internal Medicine, American University of Beirut, Beirut, Lebanon. 2. Department of Internal Medicine, Division of Endocrinology, Calcium Metabolism and Osteoporosis Program, Beirut, Lebanon. 3. Department of Rheumatology, Hotel Dieu de France, Beirut, Lebanon. 4. Department of Endocrinology, Hotel Dieu de France, Beirut, Lebanon. 5. Division of Clinical Biochemistry and Immunology, Mayo Clinic, Rochester, Minnesota. 6. Department of Chronic Diseases, Metabolism and Ageing (CHROMETA), Laboratory of Clinical and Experimental Endocrinology, KU Leuven, Herestraat, Leuven, Belgium. 7. Department of Endocrinology, University Hospitals Leuven, Herestraat, Leuven, Belgium. 8. Department of Internal Medicine, Division of Endocrinology, Katholieke Universiteit Leuven, Leuven, Belgium.
Abstract
CONTEXT: Questions regarding the superiority of free and bioavailable 25-hydroxyvitamin D [25(OH)D] in predicting health outcomes remain unresolved. OBJECTIVE: This study investigates the impact of vitamin D variables-total, bioavailable, or free 25(OH)D-on indices of bone and mineral metabolism, at baseline and in response to 2 vitamin D doses. DESIGN: Our objectives are implemented as exploratory analyses on data collected in a 1-year, double-blind, randomized controlled trial completed in July 2014. SETTING: Participants were recruited from 3 major hospitals in an ambulatory setting. PARTICIPANTS: Participants were >65 years of age, overweight, and had a baseline serum 25(OH)D between 10 and 30 ng/mL. A total of 221 participants completed the study. INTERVENTION: Subjects were randomized to receive calcium and oral vitamin D3 (600 IU/day or 3750 IU/day) supplementation. RESULTS: Participants who received the higher vitamin D dose had levels that were 1.3- to 1.4-fold higher than those taking the lower dose, for all variables (P value < 0.001). Serum values of bioavailable and free 25(OH)D were associated with total 25(OH)D, with r values of 0.942 and 0.943, respectively (P value < 0.001). Parathyroid hormone (PTH) was negatively associated with all vitamin D variables, with correlation coefficients ranging from -0.22 to -0.25, while calcium and bone turnover markers (carboxy-terminal collagen crosslinks and osteocalcin) did not. Only total 25(OH)D had a positive relationship with % change bone mineral density (BMD) at the femoral neck at 12 months, while only free and bioavailable 25(OH) had a positive relationship with % change total body BMD at 12 months. CONCLUSION: Calculated free and bioavailable 25(OH)D do not appear to be superior to total 25(OH)D in predicting indices of bone health in an elderly population.
CONTEXT: Questions regarding the superiority of free and bioavailable 25-hydroxyvitamin D [25(OH)D] in predicting health outcomes remain unresolved. OBJECTIVE: This study investigates the impact of vitamin D variables-total, bioavailable, or free 25(OH)D-on indices of bone and mineral metabolism, at baseline and in response to 2 vitamin D doses. DESIGN: Our objectives are implemented as exploratory analyses on data collected in a 1-year, double-blind, randomized controlled trial completed in July 2014. SETTING: Participants were recruited from 3 major hospitals in an ambulatory setting. PARTICIPANTS: Participants were >65 years of age, overweight, and had a baseline serum 25(OH)D between 10 and 30 ng/mL. A total of 221 participants completed the study. INTERVENTION: Subjects were randomized to receive calcium and oral vitamin D3 (600 IU/day or 3750 IU/day) supplementation. RESULTS: Participants who received the higher vitamin D dose had levels that were 1.3- to 1.4-fold higher than those taking the lower dose, for all variables (P value < 0.001). Serum values of bioavailable and free 25(OH)D were associated with total 25(OH)D, with r values of 0.942 and 0.943, respectively (P value < 0.001). Parathyroid hormone (PTH) was negatively associated with all vitamin D variables, with correlation coefficients ranging from -0.22 to -0.25, while calcium and bone turnover markers (carboxy-terminal collagen crosslinks and osteocalcin) did not. Only total 25(OH)D had a positive relationship with % change bone mineral density (BMD) at the femoral neck at 12 months, while only free and bioavailable 25(OH) had a positive relationship with % change total body BMD at 12 months. CONCLUSION: Calculated free and bioavailable 25(OH)D do not appear to be superior to total 25(OH)D in predicting indices of bone health in an elderly population.
Authors: Christine A Simpson; Jane H Zhang; Dirk Vanderschueren; Lei Fu; Teresita C Pennestri; Roger Bouillon; David E C Cole; Thomas O Carpenter Journal: J Clin Endocrinol Metab Date: 2020-04-01 Impact factor: 5.958
Authors: Pang Yao; Liang Sun; Ling Lu; Hong Ding; Xiafei Chen; Lixin Tang; Xinming Xu; Gang Liu; Yao Hu; Yiwei Ma; Feijie Wang; Qianlu Jin; He Zheng; Huiyong Yin; Rong Zeng; Yan Chen; Frank B Hu; Huaixing Li; Xu Lin Journal: J Clin Endocrinol Metab Date: 2017-01-01 Impact factor: 5.958
Authors: Paul Lips; Kevin D Cashman; Christel Lamberg-Allardt; Heike Annette Bischoff-Ferrari; Barbara Obermayer-Pietsch; Maria Luisa Bianchi; Jan Stepan; Ghada El-Hajj Fuleihan; Roger Bouillon Journal: Eur J Endocrinol Date: 2019-04 Impact factor: 6.664
Authors: Stina T Sollid; Moira Y S Hutchinson; Vivian Berg; Ole M Fuskevåg; Yngve Figenschau; Per M Thorsby; Rolf Jorde Journal: Eur J Endocrinol Date: 2016-01-05 Impact factor: 6.664
Authors: Shatha Alharazy; M Denise Robertson; Susan Lanham-New; Muhammad Imran Naseer; Adeel G Chaudhary; Eman Alissa Journal: Endocr Connect Date: 2021-12-09 Impact factor: 3.335