Context:
Public health authorities around the world recommend widely variable supplementation strategies for adults, whereas several professional organizations, including The Endocrine Society, ...recommend higher supplementation.
Methods:
We analyzed published randomized controlled clinical trials to define the optimal intake or vitamin D status for bone and extraskeletal health.
Conclusions:
The extraskeletal effects of vitamin D are plausible as based on preclinical data and observational studies. However, apart from the beneficial effects of 800 IU/d of vitamin D3 for reduction of falls in the elderly, causality remains yet unproven in randomized controlled trials (RCTs). The greatest risk for cancer, infections, cardiovascular and metabolic diseases is associated with 25-hydroxyvitamin D (25OHD) levels below 20 ng/mL. There is ample evidence from RCTs that calcium and bone homeostasis, estimated from serum 1,25-dihydroxyvitamin D and PTH, calcium absorption, or bone mass, can be normalized by 25OHD levels above 20 ng/mL. Moreover, vitamin D supplementation (800 IU/d) in combination with calcium can reduce fracture incidence by about 20%. Such a dose will bring serum levels of 25OHD above 20 ng/mL in nearly all postmenopausal women. Based on calculations of the metabolic clearance of 25OHD, a daily intake of 500–700 IU of vitamin D3 is sufficient to maintain serum 25OHD levels of 20 ng/mL. Therefore, the recommendations for a daily intake of 1500–2000 IU/d or serum 25OHD levels of 30 ng or higher for all adults or elderly subjects, as suggested by The Endocrine Society Task Force, are premature. Fortunately, ongoing RCTs will help to guide us to solve this important public health question.
Comprehensive geriatric assessment for older patients admitted to dedicated wards has proven to be beneficial, but the impact of comprehensive geriatric assessment delivered by mobile inpatient ...geriatric consultation teams remains unclear. This review and meta-analysis aims to determine the impact of inpatient geriatric consultation teams on clinical outcomes of interest in older adults.
An electronic search of Medline, CINAHL, EMBASE, Web of Science and Invert for English, French and Dutch articles was performed from inception to June 2012. Three independent reviewers selected prospective cohort studies assessing functional status, readmission rate, mortality or length of stay in adults aged 60 years or older. Twelve studies evaluating 4,546 participants in six countries were identified. Methodological quality of the included studies was assessed with the Methodological Index for Non-Randomized Studies.
The individual studies show that an inpatient geriatric consultation team intervention has favorable effects on functional status, readmission and mortality rate. None of the studies found an effect on the length of the hospital stay. The meta-analysis found a beneficial effect of the intervention with regard to mortality rate at 6 months (relative risk 0.66; 95% confidence interval 0.52 to 0.85) and 8 months (relative risk 0.51; confidence interval 0.31 to 0.85) after hospital discharge.
Inpatient geriatric consultation team interventions have a significant impact on mortality rate at 6 and 8 months postdischarge, but have no significant impact on functional status, readmission or length of stay. The reason for the lack of effect on these latter outcomes may be due to insufficient statistical power or the insensitivity of the measuring method for, for example, functional status. The questions of to whom IGCT intervention should be targeted and what can be achieved remain unanswered and require further research.
CRD42011001420 (http://www.crd.york.ac.uk/PROSPERO).
Structural gender differences in bone mass – characterized by wider but not thicker bones – are generally attributed to opposing sex steroid actions in men and women. Recent findings have redefined ...the traditional concept of sex hormones as the main regulators of skeletal sexual dimorphism. GH–IGF1 action is likely to be the most important determinant of sex differences in bone mass. Estrogens limit periosteal bone expansion but stimulate endosteal bone apposition in females, whereas androgens stimulate radial bone expansion in males. Androgens not only act directly on bone through the androgen receptor (AR) but also activate estrogen receptor-α or -β (ERα or ERβ) following aromatization into estrogens. Both the AR and ERα pathways are needed to optimize radial cortical bone expansion, whereas AR signaling alone is the dominant pathway for normal male trabecular bone development. Estrogen/ERα-mediated effects in males may – at least partly – depend on interaction with IGF1. In addition, sex hormones and their receptors have an impact on the mechanical sensitivity of the growing skeleton. AR and ERβ signaling may limit the osteogenic response to loading in males and females respectively, while ERα may stimulate the response of bone to mechanical stimulation in the female skeleton. Overall, current evidence suggests that skeletal sexual dimorphism is not just the end result of differences in sex steroid secretion between the sexes, but depends on gender differences in GH–IGF1 and mechanical sensitivity to loading as well.
Muscle adaptations can be induced by high-resistance exercise. Despite being potentially more suitable for older adults, low-resistance exercise protocols have been less investigated. We compared the ...effects of high- and low-resistance training on muscle volume, muscle strength, and force–velocity characteristics. Fifty-six older adults were randomly assigned to 12weeks of leg press and leg extension training at either HIGH (2×10–15 repetitions at 80% of one repetition maximum (1RM)), LOW (1×80–100 repetitions at 20% of 1RM), or LOW+ (1×60 repetitions at 20% of 1RM, followed by 1×10–20 repetitions at 40% of 1RM). All protocols ended with muscle failure. Leg press and leg extension of 1RM were measured at baseline and post intervention and before the first training session in weeks 5 and 9. At baseline and post intervention, muscle volume (MV) was measured by CT-scan. A Biodex dynamometer evaluated knee extensor static peak torque in different knee angles (PTstat90°, PTstat120°, PTstat150°), dynamic peak torque at different speeds (PTdyn60°s−1, PTdyn180°s−1, PTdyn240°s−1), and speed of movement at 20% (S20), 40% (S40), and 60% (S60) of PTstat90°. HIGH and LOW+ resulted in greater improvements in 1RM strength than LOW (p<0.05). These differences were already apparent after week 5. Similar gains were found between groups in MV, PTstat, PTdyn60°s−1, and PTdyn180°s−1. No changes were reported in speed of movement. HIGH tended to improve PTdyn240°s−1 more than LOW or LOW+ (p=0.064). In conclusion, high- and low-resistance exercises ending with muscle failure may be similarly effective for hypertrophy. High-resistance training led to a higher increase in 1RM strength than low-resistance training (20% of 1RM), but this difference disappeared when using a mixed low-resistance protocol in which the resistance was intensified within a single exercise set (40% of 1RM). Our findings support the need for more research on low-resistance programs in older age, in particular long-term training studies and studies focusing on residual effects after training cessation.
•High- & low-resistance exercise until muscle failure equally induce hypertrophy.•Greater 1RM gains are found in high-resistance than in low-resistance exercise.•Adding a set at 40% of 1RM after low-resistance training eliminates this difference.
Summary Background Balloon kyphoplasty is a minimally invasive procedure for the treatment of painful vertebral fractures, which is intended to reduce pain and improve quality of life. We assessed ...the efficacy and safety of the procedure. Methods Adults with one to three acute vertebral fractures were eligible for enrolment in this randomised controlled trial at 21 sites in eight countries. We randomly assigned 300 patients by a computer-generated sequence to receive kyphoplasty treatment (n=149) or non-surgical care (n=151). The primary outcome was the difference in change from baseline to 1 month in the short-form (SF)-36 physical component summary (PCS) score (scale 0–100) between the kyphoplasty and control groups. Quality of life and other efficacy measurements and safety were assessed up to 12 months. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov , number NCT00211211. Findings 138 participants in the kyphoplasty group and 128 controls completed follow-up at 1 month. By use of repeated measures mixed effects modelling, all 300 randomised participants were included in the analysis. Mean SF-36 PCS score improved by 7·2 points (95% CI 5·7–8·8), from 26·0 at baseline to 33·4 at 1 month, in the kyphoplasty group, and by 2·0 points (0·4–3·6), from 25·5 to 27·4, in the non-surgical group (difference between groups 5·2 points, 2·9–7·4; p<0·0001). The frequency of adverse events did not differ between groups. There were two serious adverse events related to kyphoplasty (haematoma and urinary tract infection); other serious adverse events (such as myocardial infarction and pulmonary embolism) did not occur perioperatively and were not related to procedure. Interpretation Our findings suggest that balloon kyphoplasty is an effective and safe procedure for patients with acute vertebral fractures and will help to inform decisions regarding its use as an early treatment option. Funding Medtronic Spine LLC.
In this double-blind, placebo-controlled trial, women with postmenopausal osteoporosis received an infusion of either zoledronic acid (5 mg) or placebo at baseline and at 1 and 2 years and were ...followed for 3 years. Zoledronic acid significantly reduced the risk of vertebral, hip, and other fractures. Adverse events were similar in the two study groups, except for serious atrial fibrillation, which was more frequent in the zoledronic acid group. This drug may provide a promising approach to reducing fracture risk.
In women with postmenopausal osteoporosis, zoledronic acid significantly reduced the risk of vertebral, hip, and other fractures. This drug may provide a promising approach to reducing fracture risk.
Fractures are an important cause of disability among postmenopausal women, and the costs of medical care associated with osteoporosis are estimated to be more than $18 billion annually in the United States alone.
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Bisphosphonates, the most commonly used treatment for established osteoporosis, inhibit osteoclast-mediated bone resorption and reduce the risk of vertebral fracture. Two bisphosphonates, alendronate and risedronate, also have been shown to reduce nonvertebral and hip fractures in women with osteoporosis.
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However, adherence to oral treatment is problematic, and about half of patients for whom oral treatment is prescribed do not adhere to it after 1 year.
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