TY - JOUR
T1 - A parallel group double-blind RCT of vitamin D3 assessing physical function
T2 - is the biochemical response to treatment affected by overweight and obesity?
AU - Wood, A. D.
AU - Secombes, K. R.
AU - Thies, F.
AU - Aucott, L. S.
AU - Black, A. J.
AU - Reid, D. M.
AU - Mavroeidi, A.
AU - Simpson, W. G.
AU - Fraser, W. D.
AU - Macdonald, H. M.
PY - 2014/1/31
Y1 - 2014/1/31
N2 - Vitamin D may affect skeletal muscle function. In a double-blind, randomised, placebo-controlled trial, we found that vitamin D3 supplementation (400 or 1,000 I.U. vs. placebo daily for 1 year with bimonthly study visits) does not improve grip strength or reduce falls. Introduction: This study aimed to test the supplementation effects of vitamin D3 on physical function and examine associations between overweight/obesity and the biochemical response to treatment. Methods: In a parallel group double-blind RCT, healthy postmenopausal women from North East Scotland (latitude - 57 N) aged 60-70 years (body mass index (BMI), 18-45 kg/m2) were assigned (computer randomisation) to daily vitamin D3 (400 I.U. (n = 102)/1,000 I.U. (n = 101)) or matching placebo (n = 102) (97, 96 and 100 participants analysed for outcomes, respectively) from identical coded containers for 1 year. Grip strength (primary outcome), falls, diet, physical activity and ultraviolet B radiation exposure were measured bimonthly, as were serum 25(OH)D, adjusted calcium (ACa) and phosphate. Fat/lean mass (dual energy X-ray absorptiometry), anthropometry, 1,25-dihydroxyvitamin D and parathyroid hormone were measured at baseline and 12 months. Participants and researchers were blinded throughout intervention and analysis. Results: Treatment had no effect on grip strength (mean change (SD)/year = -0.5 (2.5), -0.9 (2.7) and -0.4 (3.3) kg force for 400/1,000 I.U. vitamin D3 and placebo groups, respectively (P =.10, ANOVA)) or falls (P =.65, chi-squared test). Biochemical responses were similar across BMI categories (<25.25-29.99, ≥30 kg/m 2) with the exception of a small change at 12-months in serum ACa in overweight compared to non-overweight participants (P =.01, ANOVA; 1,000 I.U. group). In the placebo group, 25(OH)D peak concentration change (winter to summer) was negatively associated with weight (r = -.268), BMI (r = -.198), total (r = -.278) and trunk fat mass (r = -.251), with total and trunk fat mass predictive of winter to summer 25(OH)D change (P =.01/.004 respectively, linear regression). Conclusion: We found no evidence of an improvement in physical function following vitamin D3 supplementation for 1 year.
AB - Vitamin D may affect skeletal muscle function. In a double-blind, randomised, placebo-controlled trial, we found that vitamin D3 supplementation (400 or 1,000 I.U. vs. placebo daily for 1 year with bimonthly study visits) does not improve grip strength or reduce falls. Introduction: This study aimed to test the supplementation effects of vitamin D3 on physical function and examine associations between overweight/obesity and the biochemical response to treatment. Methods: In a parallel group double-blind RCT, healthy postmenopausal women from North East Scotland (latitude - 57 N) aged 60-70 years (body mass index (BMI), 18-45 kg/m2) were assigned (computer randomisation) to daily vitamin D3 (400 I.U. (n = 102)/1,000 I.U. (n = 101)) or matching placebo (n = 102) (97, 96 and 100 participants analysed for outcomes, respectively) from identical coded containers for 1 year. Grip strength (primary outcome), falls, diet, physical activity and ultraviolet B radiation exposure were measured bimonthly, as were serum 25(OH)D, adjusted calcium (ACa) and phosphate. Fat/lean mass (dual energy X-ray absorptiometry), anthropometry, 1,25-dihydroxyvitamin D and parathyroid hormone were measured at baseline and 12 months. Participants and researchers were blinded throughout intervention and analysis. Results: Treatment had no effect on grip strength (mean change (SD)/year = -0.5 (2.5), -0.9 (2.7) and -0.4 (3.3) kg force for 400/1,000 I.U. vitamin D3 and placebo groups, respectively (P =.10, ANOVA)) or falls (P =.65, chi-squared test). Biochemical responses were similar across BMI categories (<25.25-29.99, ≥30 kg/m 2) with the exception of a small change at 12-months in serum ACa in overweight compared to non-overweight participants (P =.01, ANOVA; 1,000 I.U. group). In the placebo group, 25(OH)D peak concentration change (winter to summer) was negatively associated with weight (r = -.268), BMI (r = -.198), total (r = -.278) and trunk fat mass (r = -.251), with total and trunk fat mass predictive of winter to summer 25(OH)D change (P =.01/.004 respectively, linear regression). Conclusion: We found no evidence of an improvement in physical function following vitamin D3 supplementation for 1 year.
KW - adiposity
KW - body mass index
KW - falls
KW - grip strength
KW - RCT
KW - vitamin D
KW - physical function
UR - http://www.scopus.com/inward/record.url?scp=84891852429&partnerID=8YFLogxK
U2 - 10.1007/s00198-013-2473-8
DO - 10.1007/s00198-013-2473-8
M3 - Article
C2 - 23982800
AN - SCOPUS:84891852429
SN - 0937-941X
VL - 25
SP - 305
EP - 315
JO - Osteoporosis International
JF - Osteoporosis International
IS - 1
ER -