Conclusions and Relevance In this systematic review and meta- analysis , neither intermittent nor daily dosing with st and ard doses of vitamin D alone was associated with reduced risk of fracture , but daily supplementation with both vitamin D and calcium was a more promising strategy
Importance Vitamin D and calcium supplements are recommended for the prevention of fracture , but previous r and omized clinical trials ( RCTs ) have reported conflicting results , with uncertainty about optimal doses and regimens for supplementation and their overall effectiveness .
Objective To assess the risks of fracture associated with differences in concentrations of 25-hydroxyvitamin D ( 25[OH]D ) in observational studies and the risks of fracture associated with supplementation with vitamin D alone or in combination with calcium in RCTs .
Low serum levels of 25-hydroxyvitamin D predict hip fracture in the elderly: a NOREPOS study.
BACKGROUND Despite considerable interest , the relationship between circulating 25-hydroxyvitamin D and the risk of hip fracture is not fully established . OBJECTIVE The objective of the study was to study the association between serum 25-hydroxyvitamin D concentrations [ s-25(OH)D ] and the  risk of hip fracture in Norway , a high-latitude country that has some of the highest hip fracture rates worldwide . METHODS A total of 21 774 men and women aged 65 - 79 years attended 4 community-based health studies during 1994 - 2001 . Information on subsequent hip fractures was retrieved from electronic hospital discharge registers , with a maximum follow-up of 10.7 years . Using a stratified case-cohort design , s-25(OH)D was determined by HPLC-atmospheric pressure chemical ionization-mass spectrometry in stored serum sample s in hip fracture cases ( n = 1175 ; 307 men , 868 women ) and in gender-stratified r and om sample s ( n = 1438 ) . Cox proportional hazards regression adapted for the case-cohort design was performed . RESULTS We observed an inverse association between s-25(OH)D and hip fracture ; those with s-25(OH)D in the lowest quartile ( < 42.2 nmol/L ) had a 38 % [ 95 % confidence interval ( CI ) 9 - 74 % ] increased risk of hip fracture compared with the highest quartile ( ≥67.9 nmol/L ) in a model accounting for age , gender , study center , and body mass index . The association was stronger in men than in women : hazard ratio 1.65 ( 95 % CI 1.04 - 2.61 ) vs hazard ratio 1.25 ( 95 % CI 0.95 - 1.65 ) . CONCLUSION In this prospect i ve case-cohort study of hip fractures , the largest ever reported , we found an increased risk of hip fracture in subjects in the lowest compared with the highest quartile of serum 25-hydroxyvitamin D. In accordance with the findings of previous community-based studies , low vitamin D status was a modest risk factor for hip fracture
Conclusions and Relevance In this systematic review and meta- analysis , neither intermittent nor daily dosing with st and ard doses of vitamin D alone was associated with reduced risk of fracture , but daily supplementation with both vitamin D and calcium was a more promising strategy
Importance Vitamin D and calcium supplements are recommended for the prevention of fracture , but previous r and omized clinical trials ( RCTs ) have reported conflicting results , with uncertainty about optimal doses and regimens for supplementation and their overall effectiveness .
Objective To assess the risks of fracture associated with differences in concentrations of 25-hydroxyvitamin D ( 25[OH]D ) in observational studies and the risks of fracture associated with supplementation with vitamin D alone or in combination with calcium in RCTs .