Hip fracture risk in relation to vitamin D supplementation and serum 25-hydroxyvitamin D levels: a systematic review and meta-analysis of randomised controlled trials and observational studies

<p>Abstract</p> <p>Background</p> <p>Vitamin D supplementation for fracture prevention is widespread despite conflicting interpretation of relevant randomised controlled trial (RCT) evidence. This study summarises quantitatively the current evidence from RCTs and observational studies regarding vitamin D, parathyroid hormone (PTH) and hip fracture risk.</p> <p>Methods</p> <p>We undertook separate meta-analyses of RCTs examining vitamin D supplementation and hip fracture, and observational studies of serum vitamin D status (25-hydroxyvitamin D (25(OH)D) level), PTH and hip fracture. Results from RCTs were combined using the reported hazard ratios/relative risks (RR). Results from case-control studies were combined using the ratio of 25(OH)D and PTH measurements of hip fracture cases compared with controls. Original published studies of vitamin D, PTH and hip fracture were identified through PubMed and Web of Science databases, searches of reference lists and forward citations of key papers.</p> <p>Results</p> <p>The seven eligible RCTs identified showed no significant difference in hip fracture risk in those randomised to cholecalciferol or ergocalciferol supplementation versus placebo/control (RR = 1.13[95%CI 0.98-1.29]; 801 cases), with no significant difference between trials of <800 IU/day and ≥800 IU/day. The 17 identified case-control studies found 33% lower serum 25(OH)D levels in cases compared to controls, based on 1903 cases. This difference was significantly greater in studies with population-based compared to hospital-based controls (χ²₁(heterogeneity) = 51.02, p < 0.001) and significant heterogeneity was present overall (χ²₁₆(heterogeneity) = 137.9, p < 0.001). Serum PTH levels in hip fracture cases did not differ significantly from controls, based on ten case-control studies with 905 cases (χ²₉(heterogeneity) = 149.68, p < 0.001).</p> <p>Conclusions</p> <p>Neither higher nor lower dose vitamin D supplementation prevented hip fracture. Randomised and observational data on vitamin D and hip fracture appear to differ. The reason for this is unclear; one possible explanation is uncontrolled confounding in observational studies. Post-fracture PTH levels are unrelated to hip fracture risk.</p

CROSS-NATIONAL INVARIANCE OF DIMENSIONS OF PARENTAL REARING BEHAVIOR - COMPARISON OF PSYCHOMETRIC DATA OF SWEDISH DEPRESSIVES AND HEALTHY-SUBJECTS WITH DUTCH TARGET RATINGS ON THE EMBU

Conducted a psychometric study on 205 healthy Swedish Ss (mean age 24.9 yrs) and 141 depressed Swedish inpatients (mean age 49.5 yrs) and 277 healthy Dutch Ss (mean age 41.1 yrs) and 841 Dutch phobics (mean age 42.2 yrs), using the EMBU, a self-report instrument designed to assess memories of parents' rearing behavior. Of the 4 primary factors identified previously with Dutch Ss (Rejection, Emotional Warmth, Overprotection, and Favoring Subject), the 1st 3 were retrieved in a similar form in the 2 Swedish groups. Examination of the metric equivalence of the scales and the strength of the factors from each group indicated that comparisons of patterns and levels between groups from the respective countries on the 3 factors showing cross-national constancy would be warranted. Scale-level factor analyses of these dimensions produced identical 2-factor compositions across national groups, which further supported this conclusio