Associations of 25-Hydroxyvitamin D and 1,25-Dihydroxyvitamin D With Bone Mineral Density, Bone Mineral Density Change, and Incident Nonvertebral Fracture

Relationship Between Serum 25-Hydroxyvitamin D and Bone Mineral Density, Fracture Risk, and Bone Metabolism in Adults With Osteoporosis/Fractures

OBJECTIVE

To evaluate the association of serum 25-hydroxyvitamin D (25(OH) D) levels with bone mineral density (BMD), fracture risk, and bone metabolism.

METHODS

This multicenter cross-sectional study recruited menopausal females and males greater than or equal to 50 year old with osteoporosis/fractures between September 2016 and September 2021. Assessment included clinical data, 25(OH)D, intact parathyroid hormone (iPTH), procollagen type 1 amino-terminal propeptide (P1NP), carboxy-terminal collagen crosslinks (CTX), lateral thoracolumbar spine x-rays, and BMD.

RESULTS

A total of 3003 individuals were stratified by 25(OH) D levels: 720 individuals (24%) <20 ng/mL, 1338 individuals (44.5%) 20 to 29 ng/mL, and 945 individuals (31.5%) ≥30 ng/mL. In unadjusted and multivariable models, BMD T-score, except spine, was significantly and positively associated with 25(OH)D levels. 25(OH) D levels were inversely associated with Fracture Risk Assessment Tool scores. Patients with 25(OH)D <20 ng/mL had significantly higher iPTH and bone turnover markers (P1NP and CTX) than patients with 25(OH)D ≧20 ng/mL in all models. When analyzing bone-related markers and BMD, total hip and femoral neck BMD T-scores were positively correlated with 25(OH)D concentrations and BMI but negatively correlated with iPTH, P1NP, CTX, and age. In multivariate models with all bone-related markers, only 25(OH)D levels were significantly associated with total hip and femoral neck BMD.

CONCLUSION

Vitamin D deficiency is significantly associated with decreased total hip and femoral neck BMD and increased fracture risk as assessed by Fracture Risk Assessment Tool. In those with osteoporosis/fractures, vitamin D is implicated in the causal relationship between bone remodeling and BMD. Assessing vitamin D status is imperative for those at risk for osteoporosis/fractures.

Abnormal changes of bone metabolism markers with age in children with cerebral palsy

Cerebral palsy (CP) is a broad range of diseases with permanent and nonprogressive motor impairments, carrying a high cost for both the individual and the society. The characteristics of low bone mineral density and high risk of fractures suggest that bone metabolism disorders are present in CP. This study aims to investigate the association between indicators of bone metabolism and children with CP. A total of 139 children (75 children with CP and 64 healthy controls) were included in this cross-sectional study. Participants were divided into three age groups (0-2 years, 2.1-4 years, and 4.1-7 years). All children with CP were diagnosed according to clinical criteria and furtherly divided into clinical subtypes. The levels of total procollagen type I N-terminal propeptide (TPINP), N-MID osteocalcin (OC), beta-crosslaps (β-CTX), 25-hydroxyvitamin D (25-OHD) and parathyroid hormone (PTH) in the serum were measured with corresponding detection kits according to the manufacturer's instructions. Serum levels of TPINP and 25-OHD were lower with older age, whereas β-CTX and PTH were higher with older age. In the CP group, TPINP (age 0-2 years and 2.1-4 years) and OC (age 2.1-4 years) levels were higher, while β-CTX (age 2.1-4 years and 4.1-7 years) and PTH (age 2.1-4 years) values were lower than the control group. In addition, there were no statistically significant differences in the levels of these indicators among the CP subgroups with different clinical characteristics. Our study shows that bone turnover markers, indicators of bone metabolism, in children with CP differ significantly from healthy controls. The indicators we studied changed with age, and they did not correlate with disease severity.

Scientific opinion on the tolerable upper intake level for vitamin D, including the derivation of a conversion factor for calcidiol monohydrate

Following two requests from the European Commission (EC), the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on the revision of the tolerable upper intake level (UL) for vitamin D and to propose a conversion factor (CF) for calcidiol monohydrate into vitamin D3 for labelling purposes. Vitamin D refers to ergocalciferol (vitamin D2), cholecalciferol (vitamin D3), and calcidiol monohydrate. Systematic reviews of the literature were conducted to assess the relative bioavailability of calcidiol monohydrate versus vitamin D3 on serum 25(OH)D concentrations, and for priority adverse health effects of excess vitamin D intake, namely persistent hypercalcaemia/hypercalciuria and endpoints related to musculoskeletal health (i.e. falls, bone fractures, bone mass/density and indices thereof). Based on the available evidence, the Panel proposes a CF for calcidiol monohydrates of 2.5 for labelling purposes. Persistent hypercalciuria, which may be an earlier sign of excess vitamin D than persistent hypercalcaemia, is selected as the critical endpoint on which to base the UL for vitamin D. A lowest-observed-adverse-effect-level (LOAEL) of 250 μg/day is identified from two randomised controlled trials in humans, to which an uncertainty factor of 2.5 is applied to account for the absence of a no-observed-adverse-effect-level (NOAEL). A UL of 100 μg vitamin D equivalents (VDE)/day is established for adults (including pregnant and lactating women) and for adolescents aged 11-17 years, as there is no reason to believe that adolescents in the phase of rapid bone formation and growth have a lower tolerance for vitamin D compared to adults. For children aged 1-10 years, a UL of 50 μg VDE/day is established by considering their smaller body size. Based on available intake data, European populations are unlikely to exceed the UL, except for regular users of food supplements containing high doses of vitamin D.

Circulating vitamin D levels and colorectal cancer risk: A meta-analysis and systematic review of case-control and prospective cohort studies

The associations between circulating vitamin D concentrations and total and site-specific colorectal cancer (CRC) incidence have been examined in several epidemiological studies with overall inconclusive findings. The aim of this systematic review and meta-analysis of both case-control and prospective cohort studies was to evaluate the association between CRC and circulating levels of vitamin D. The main exposure and outcome were circulating total 25(OH)D and CRC, respectively, in the overall population (i.e., all subjects). Two reviewers, working independently, screened all the literature available to identify studies that met the inclusion criteria (e.g., case-control or prospective cohort studies, published in English, and excluding non-original papers). Data were pooled by the generic inverse variance method using a random or fixed effect model, as approriate. Heterogeneity was identified using the Cochran's Q-test and quantified by the I² statistic. Results were stratified by study design, sex, and metabolite of vitamin D. Sensitivity and subgroup analyses were also performed. A total of 28 original studies were included for the quantitative meta-analysis. Meta-analyses comparing the highest vs lowest categories, showed a 39% lower risk between levels of total 25(OH)D and CRC risk (OR (95% CI): 0.61 (0.52; 0.71); 11 studies) in case-control studies; whereas a 20% reduced CRC risk in prospective cohort studies (HR (95% CI): 0.80 (0.66; 0.97); 6 studies). Results in women mirrored main results, whereas results in men were non-significant in both analyses. Our findings support an inverse association between circulating vitamin D levels and CRC risk.

Bone health in ageing men

Osteoporosis does not only affect postmenopausal women, but also ageing men. The burden of disease is projected to increase with higher life expectancy both in females and males. Importantly, osteoporotic men remain more often undiagnosed and untreated compared to women. Sex steroid deficiency is associated with bone loss and increased fracture risk, and circulating sex steroid levels have been shown to be associated both with bone mineral density and fracture risk in elderly men. However, in contrast to postmenopausal osteoporosis, the contribution of relatively small decrease of circulating sex steroid concentrations in the ageing male to the development of osteoporosis and related fractures, is probably only minor. In this review we provide several clinical and preclinical arguments in favor of a 'bone threshold' for occurrence of hypogonadal osteoporosis, corresponding to a grade of sex steroid deficiency that in general will not occur in many elderly men. Testosterone replacement therapy has been shown to increase bone mineral density in men, however data in osteoporotic ageing males are scarce, and evidence on fracture risk reduction is lacking. We conclude that testosterone replacement therapy should not be used as a sole bone-specific treatment in osteoporotic elderly men.

Relationship between serum vitamin D and hip fracture in the elderly: a systematic review and meta-analysis

INTRODUCTION

This study investigated the relationship between serum 25-hydroxyvitamin D (25OHD) levels and the occurrence of hip fractures in the elderly using a systematic review and meta-analysis approach.

MATERIALS AND METHODS

PubMed, Web of Science, and Scopus were used to identify studies that outlined an association between serum 25OHD and the occurrence of a hip fracture in a geriatric patient. The analysis calculated odds ratios (OR) for a hip fracture using a random-effects model.

RESULTS

In this study, 28 studies were included, 61,744 elderlies and 9767 cases (15.81%) of hip fractures. In the lowest vs. highest categories of vitamin D in the elderly, pooled OR of hip fractures was 1.80 (95% CI 1.56-2.07, P ≤ 0.001), and modified OR was equal to 1.40 (95% CI 1.20-1.63 P ≤ 0.001). A subgroup analysis showed that the OR of a hip fracture was 2.16 (1.49-3.11, P ≤ 0.001) in case-control studies; 1.52 (1.29-1.79, P = 0.001) in cohort studies; and 1.41 (1.18-1.70, P ≤ 0.001) in case-cohort studies.

CONCLUSION

Low serum vitamin D levels in the elderly are associated with an increase in the odds of hip fracture.

Porous gelatin microsphere-based scaffolds containing MC3T3-E1 cells and calcitriol for the repair of skull defect

There is an increasing demand for biomaterials with skull regeneration for clinical application. However, most of the current skull repair materials still have limitations, such as inadequate sources, poor cell adherence, differentiation, tissue infiltration, and foreign body sensation. Therefore, this study developed porous microsphere-based scaffolds containing mouse embryonic osteoblast precursor cells (MC3T3-E1 cells) and calcitriol (Cal) using gelatin and gelatin/hydroxyapatite through green freeze-crosslinking and freeze-drying. Gelatin was employed to prepare porous microspheres with a particle size of 100-300 μm, containing open pores of 2-70 μm and interconnected paths. Furthermore, the addition of Cal to porous gelatin microsphere-based scaffolds containing MC3T3-E1 cells (PGMSs-MC) and porous gelatin/hydroxyapatite composite microspheres containing MC3T3-E1 cells (HPGMSs-MC) improved their osteoinductivity and cell proliferation and promoted the formation of mature and well-organized bone. The developed Cal-HPGMSs-MC and Cal-PGMSs-MC displayed a good porous structure and cytocompatibility, histocompatibility, osteoconductivity, and osteoinduction. Thus, the designed scaffolds provide a promising prospect for tissue-engineered constructs with skull growth and integration, laying a foundation for further research on the reconstruction of skull defects.

Management of osteoporosis in older men

As many as one out of three fragility fractures occur in older men and the outcome of major osteoporotic fractures, in particular hip fractures, is worse in men than in women. Osteoporosis in older men is thus an important threat to the quality of life of individual patients and a considerable burden for society. However, only a small minority of older men with high or very high fracture risk are receiving therapy. This does not need to be so as tools for fracture risk assessment are available and several drugs have been approved for treatment. Nevertheless, the evidence base for the management of osteoporosis in older men remains limited. This narrative review summarises the evidence for older men on the burden of osteoporosis, the pathophysiology of fragility fractures, the clinical presentation, diagnosis and risk assessment, the patient evaluation, and the non-pharmacological and pharmacological management.

The relationship between serum vitamin D and fracture risk in the elderly: a meta-analysis

BACKGROUND

The incidence of osteoporotic fractures has increased rapidly, and because of the poor prognosis and high mortality associated with osteoporotic fractures, they remain a prospective research area globally. One way to reduce their incidence is to investigate their intervention risk factors in the elderly. Hence, this study explores the correlation between serum 25-hydroxyvitamin D [25(OH)D] levels and osteoporotic fractures in elderly patients through a meta-analysis.

METHODS

We conducted our literature search mainly in PubMed and Embase for identifying studies that investigated the relationship between serum 25(OH)D levels and the risk for osteoporotic fractures. We performed categorical analysis, heterogeneity checks, publication bias analysis, and subgroup analyses.

RESULTS

In total, 20 studies were included, of which 4 were case-cohort studies and 16 were cohort studies. A total of 41,738 patients from 20 studies were included in the meta-analysis, of which 5916 had fractures, including 3237 hip fractures. By combining the lowest and highest categories of relative risks (RRs) and 95% confidence intervals (CIs), it was suggested that lower serum 25-hydroxyvitamin D levels may be a risk factor for fractures. RR (95% CI) for total and hip fractures were 1.11 (0.99, 1.24) and 0.89 (0.80, 0.98) after adjustments.

CONCLUSIONS

Our study showed that compared to low serum 25(OH)D levels, high serum 25(OH)D levels reduce the risk of hip fractures in the patients aged 60 years or older. In contrast, serum 25(OH)D has no significant relationship with total fracture risk.

Analysis of Related Factors of Brittle Hip Fracture in Postmenopausal Women with Osteoporosis

OBJECTIVE

To investigate the effects of age, body mass index (BMI), bone mineral density (BMD), and levels of serum 25-hydroxyvitamin D (25OHD) on hip fracture on the condition of the bone density of femoral neck having reached the threshold of osteoporosis.

METHODS

A total of 252 postmenopausal women patients, whose bone density had reached the threshold of osteoporosis and age ≥50 years (50-98 years), collected from the Second Affiliated Hospital of Fujian Medical University from January 2015 to December 2018, were performed by retrospective analysis. According to whether or not they had a hip fracture, including femoral neck fracture or intertrochanteric fracture, the patients were divided into two groups, including 117 cases (50-84 years old) in the non-hip fracture group and 135 cases (57-98 years old) in the hip fracture group. BMD was measured by Hologic Discovery A DXA bone mineral densitometer. Levels of serum 25OHD were detected by ROCHE detection instrument. Comparisons of age, BMI, bone density of femoral neck, and levels of serum 25OHD between the two groups were performed by using the Student's t-test. Furthermore, the statistically significant factors were analyzed by multiple regression analysis to investigate the independent risk factors of hip fracture.

RESULTS

The group without hip fracture: 117 cases; average age: 67.4 ± 8.5 years; BMI: 22.3 ± 3.2 kg/m2 ; bone density of femoral neck: (0.504 ± 0.067) g/cm2 ; T-value of femoral neck: -3.1 ± 0.6; levels of serum 25OHD: (24.9 ± 8.5) ng/mL. The group with brittle hip fracture: 135 cases; average age: 80.7 ± 7.6 years; BMI: 20.3 ± 3.5 kg/m2 ; bone density of femoral neck: (0.426 ± 0.077) g/cm2 ; T-value of femoral neck: -3.8 ± 0.7; levels of serum 25OHD: (15.9 ± 8.9) ng/mL. Age, BMI, bone density of femoral neck, and 25OHD level of the group without hip fracture were markedly lower than hip fracture group (P < 0.05). The results of logistic regression analysis suggested that age, bone density of femoral neck, and levels of serum 25OHD were independent risk factors for fragile hip fracture on the condition of the bone density of femoral neck having reached the threshold of osteoporosis.

CONCLUSION

Higher age, lower levels of bone density and 25OHD are the main risk factors of hip fracture on the condition of the bone density of femoral neck having reached the threshold of osteoporosis.

Do Vitamin D Level and Dietary Calcium Intake Modify the Association Between Loop Diuretics and Bone Health?

Loop diuretics (LD) may affect bone health by inhibiting renal calcium reuptake. However, whether vitamin D status and dietary calcium intake modify the association between LD and bone outcome is unclear. Therefore, this study aimed to evaluate whether vitamin D level or calcium intake modify the association between LD and various indices of bone health including bone mineral density (BMD) and Trabecular Bone Score (TBS). From The Rotterdam Study, a prospective population-based cohort study, we used data from 6990 participants aged > 45 year with a DXA scan (2002-2008), 6908 participants with femoral neck (FN)-BMD, 6677 participants with lumbar spine (LS)-BMD and 6476 participants with LS-TBS measurements. Use of LD was available from pharmacy dispensing records. Vitamin D (25(OH)D) level was measured in serum, and dietary calcium intake was measured with a validated food frequency questionnaire. Almost eight percent of the participants used LD. The association between LD (past-users compared to never-users) and LS-TBS was significantly different by 25(OH)D concentrations (P for interaction = 0.04). A significantly lower LS-TBS among LD past-users was observed for 25(OH)D ≥ 50 nmol/l compared to ≤ 20 and 20-50 nmol/l (β = - 0.036, 95% CI - 0.060; - 0.013 vs. β = - 0.012, 95% CI - 0.036; 0.013 and β = - 0.031, 95% CI - 0.096; 0.034, respectively). However, no other significant effect modification by 25(OH)D and dietary calcium intake was found in the associations between LD use and bone health outcomes (P-interaction > 0.13). This study suggests that the association between LD use and indices of bone health is not consistently modified by vitamin D or dietary calcium intake.

Vitamin D and Calcium for the Prevention of Fracture: A Systematic Review and Meta-analysis

Importance

Vitamin D and calcium supplements are recommended for the prevention of fracture, but previous randomized 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.

Data Sources

PubMed, EMBASE, Cochrane Library, and other RCT databases were searched from database inception until December 31, 2018. Searches were performed between July 2018 and December 2018.

Study Selection

Observational studies involving at least 200 fracture cases and RCTs enrolling at least 500 participants and reporting at least 10 incident fractures were included. Randomized clinical trials compared vitamin D or vitamin D and calcium with control.

Data Extraction and Synthesis

Two researchers independently extracted data according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and assessed possible bias. Rate ratios (RRs) were estimated using fixed-effects meta-analysis. Data extraction and synthesis took place between July 2018 and June 2019.

Main Outcomes and Measures

Any fracture and hip fracture.

Results

In a meta-analysis of 11 observational studies (39 141 participants, 6278 fractures, 2367 hip fractures), each increase of 10.0 ng/mL (ie, 25 nmol/L) in 25 (OH)D concentration was associated with an adjusted RR for any fracture of 0.93 (95% CI, 0.89-0.96) and an adjusted RR for hip fracture of 0.80 (95% CI, 0.75-0.86). A meta-analysis of 11 RCTs (34 243 participants, 2843 fractures, 740 hip fractures) of vitamin D supplementation alone (daily or intermittent dose of 400-30 000 IU, yielding a median difference in 25[OH]D concentration of 8.4 ng/mL) did not find a reduced risk of any fracture (RR, 1.06; 95% CI, 0.98-1.14) or hip fracture (RR, 1.14; 95% CI, 0.98-1.32), but these trials were constrained by infrequent intermittent dosing, low daily doses of vitamin D, or an inadequate number of participants. In contrast, a meta-analysis of 6 RCTs (49 282 participants, 5449 fractures, 730 hip fractures) of combined supplementation with vitamin D (daily doses of 400-800 IU, yielding a median difference in 25[OH]D concentration of 9.2 ng/mL) and calcium (daily doses of 1000-1200 mg) found a 6% reduced risk of any fracture (RR, 0.94; 95% CI, 0.89-0.99) and a 16% reduced risk of hip fracture (RR, 0.84; 95% CI, 0.72-0.97).

Conclusions and Relevance

In this systematic review and meta-analysis, neither intermittent nor daily dosing with standard 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.

The Regulation of Marrow Fat by Vitamin D: Molecular Mechanisms and Clinical Implications

PURPOSE OF REVIEW

To review the available literature regarding a possible relationship between vitamin D and bone marrow adipose tissue (BMAT), and to identify future avenues of research that warrant attention.

RECENT FINDINGS

Results from in vivo animal and human studies all support the hypothesis that vitamin D can suppress BMAT expansion. This is achieved by antagonizing adipogenesis in bone marrow stromal cells, through inhibition of PPARγ2 activity and stimulation of pro-osteogenic Wnt signalling. However, our understanding of the functions of BMAT is still evolving, and studies on the role of vitamin D in modulating BMAT function are lacking. In addition, many diseases and chronic conditions are associated with low vitamin D status and low bone mineral density (BMD), but BMAT expansion has not been studied in these patient populations. Vitamin D suppresses BMAT expansion, but its role in modulating BMAT function is poorly understood.

Vitamin D Deficiency/Insufficiency Is Associated with Risk of Osteoporotic Thoracolumbar Junction Vertebral Fractures

Background

The association between serum vitamin D level and vertebral fracture (VFx) remains controversial. The purpose of this study was to determine whether serum 25-hydroxy vitamin D (25(OH)D) level is associated with osteoporotic thoracolumbar junction VFx in elderly patients.

Material/Methods

From Jan 2013 to Dec 2017, this retrospective case-control study included 534 patients with primary osteoporotic thoracolumbar junction VFx (T10–L2) and 569 elderly orthopedic patients with back pain (without osteoporotic VFx) as controls. Serum 25(OH)D levels were measured and the association with osteoporotic VFx was analyzed. Other clinical data, including BMI, comorbidities, and bone mineral density (BMD), were also collected and compared between these 2 groups.

Results

It was shown that 25(OH)D levels were significantly lower in patients with T10–L2 VFx than in control patients. Among 534 VFx patients, 417 (78.1%) patients showed grade 2–3 fracture. Serum 25(OH)D levels were significantly related to affected vertebral numbers and VFx severities. The VFx risk was 28% lower (OR=0.72, 95% CI 0.62–0.83) per increased SD in serum 25(OH)D. Compared with the 1^st quartile (mean 25(OH)D: 29.67±6.18 nmol/L), the VFx risk was significantly lower in the 3^rd (mean 25(OH)D: 60.91±5.12nmol/L) and 4^th quartiles (mean 25(OH)D: 103.3±44.21nmol/L), but not in the 2^nd quartile (mean 25(OH)D: 45.40±3.95 nmol/L). In contrast, the VFx risk was significantly increased in the 1^st quartile (OR=1.87, 95% CI 1.42–2.45) compared with the 2^nd–4^th quartiles.

Conclusions

Vitamin D deficiency/insufficiency was associated with risk of osteoporotic thoracolumbar junction vertebral fractures in elderly patients.

Relationship between 1,25-Dihydroxyvitamin D and Body Composition in Middle-Aged Sedentary Adults: The FIT-AGEING Study

Vitamin D deficiency is a worldwide health problem that, in addition to its well-known negative effects on musculoskeletal health, has been related to a wide range of acute and chronic age-related diseases. However, little is known about the association of body composition with the active, hormonal form of vitamin D, 1,25-dihydroxyvitamin D plasma levels (1,25(OH)₂D). Therefore, the aim of this study was to investigate the association of 1,25(OH)₂D with body composition including lean and fat body mass as well as bone mineral density (BMD) in middle-aged sedentary adults. A total of 73 (39 women) middle-aged sedentary adults (53.7 ± 5.1 years old) participated in the current study. We measured weight and height, and we used dual energy X-ray absorptiometry to measure lean body mass, fat body mass and BMD. Body mass index (BMI), lean mass index (LMI), and fat mass index (FMI) were calculated. 1,25(OH)₂D was measured using a DiaSorin Liaison® immunochemiluminometric analyzer. The results showed a negative association of 1,25(OH)₂D with BMI, LMI and BMD (β = −0.274, R² = 0.075, p = 0.019; β = −0.268, R² = 0.072, p = 0.022; and β = −0.325, R² = 0.105, p = 0.005, respectively), which persisted after controlling for age and sex. No significant differences in 1,25(OH)₂D across body weight status were observed after controlling for the same covariates. In summary, our results suggest that 1,25(OH)₂D could be negatively associated with BMI, LMI and BMD whereas no association was found with FMI in middle-aged sedentary adults.

Vitamin D as a Biomarker of Ill Health among the Over-50s: A Systematic Review of Cohort Studies

Background: The association between circulating levels of vitamin D and the incidence of chronic diseases is known. The identification of vitamin D as a biomarker of physiological/pathological ageing could contribute to expanding current knowledge of its involvement in healthy ageing. Methods: According to PRISMA guidelines, a systematic review was conducted on cohorts studying the role of 25OH-Vitamin D [25(OH)D] and 1,25(OH)₂-Vitamin D [1,25(OH)₂D] concentrations as biomarkers of healthy ageing. We consulted MedLine, Scopus, and Web of Science to search for studies on the association between vitamin D status in populations of originally healthy adults, and outcomes of longevity, illness, and physical and cognitive functionality. The quality of the studies was assessed using the Newcastle Ottawa scale. Results: Twenty cohorts from 24 articles were selected for this review. Inverse associations were found between low 25(OH)D levels and all-cause mortality, respiratory and cardiovascular events, as well as markers relating to hip and non-vertebral fractures. Associations between 1,25(OH)₂D and healthy ageing outcomes gave similar results, although of lower clinical significance. Conclusions: This systematic review pinpoints peculiar aspects of vitamin D as a multidimensional predictor of ill health in the ageing process. Further well-designed controlled trials to investigate whether vitamin D supplement results in superior outcomes are warranted in the future.

Prevalence of vitamin D insufficiency and evidence for disease prevention in the older population

The prevalence of vitamin D insufficiency, usually assessed by the analysis of circulating 25-hydroxyvitamin D (25[OH])D), is very high in the aging German population. An important factor that reduces endogenous vitamin D synthesis in older persons is physical inactivity or care-dependency that limits the time spent outside. Additionally, it has been suggested that the age-dependent decline in the glomerular filtration rate is associated with a reduced production of bioactive calcitriol. As this phenomenon is not detectable by the assessment of 25(OH)D, it is necessary to analyze the level of parathyroid hormone as a marker of calcitriol function. Because 25(OH)D levels are highly correlated with an active and healthy life style, data from epidemiological studies are not necessarily suitable to elucidate the role of vitamin D in disease prevention. Recently published meta-analyses of randomized controlled trials (RCTs) showed moderate effects of vitamin D supplementation on fracture risk and found that vitamin D was more effective when administered in combination with calcium. The role of vitamin D in the prevention of falls and frailty remains unclear. Much evidence has demonstrated the beneficial effects of vitamin D on respiratory tract infections and asthma, which are very relevant health issues in the older population. To conclude, vitamin D, particularly combined with calcium, has moderately beneficial effects on the skeletal system and is useful for the prevention of respiratory tract infections.

Predictors of change of trabecular bone score (TBS) in older men: results from the Osteoporotic Fractures in Men (MrOS) Study

Among older men, characteristics that predict longitudinal changes in trabecular bone score (TBS) are different from characteristics that predict changes in bone mineral density (BMD). Most notably, weight loss is strongly associated with concomitant loss in BMD but with concomitant increases in TBS, when measured on Hologic densitometers.

INTRODUCTION

Our objective was to compare and contrast predictors of changes in TBS, total hip BMD, and lumbar spine BMD.

METHODS

Our study population was 3969 Osteoporotic Fractures in Men (MrOS) cohort participants (mean age 72.8 years) with repeat measures of TBS, lumbar spine and total hip BMD, body mass index (BMI) less than 37 kg/m2, and no use of bisphosphonate or glucocorticoid medications. TBS was scored (Med-Imaps Software version 2.1) and BMD measured on Hologic densitometers.

RESULTS

One thousand four hundred forty-four men had a TBS decrease > 0.04 units (estimated least significant change for TBS), 795 men had a TBS increase > 0.04 units, and 1730 men had TBS change ≤ 0.04 units over mean follow-up of 4.6 years. Older age was not associated with TBS change, but was associated with greater decline in lumbar spine and total hip BMD. Compared to stable weight, > 10% weight loss was strongly associated with an increase in TBS [effect size = 1.24 (95% CI 1.12, 1.36)] and strongly associated with a decrease in total hip BMD [- 1.16 (95% CI - 1.19, - 1.03)]. Other predictors discordant for longitudinal changes of TBS and BMD included baseline BMI, walk speed, and ACE inhibitor use.

CONCLUSIONS

Predictors of changes in TBS are different from predictors of changes in lumbar spine and total hip BMD. At least when assessed on Hologic densitometers, weight loss is associated with subsequent declines in spine and total hip BMD but subsequent increase in TBS. Faster walk speed may protect against loss of hip BMD, but is not associated with longitudinal changes of TBS.

Protecting Bone Health in Pediatric Rheumatic Diseases: Pharmacological Considerations

Bone health in children with rheumatic conditions may be compromised due to several factors related to the inflammatory disease state, delayed puberty, altered life style, including decreased physical activities, sun avoidance, suboptimal calcium and vitamin D intake, and medical treatments, mainly glucocorticoids and possibly some disease-modifying anti-rheumatic drugs. Low bone density or even fragility fractures could be asymptomatic; therefore, children with diseases of high inflammatory load, such as systemic onset juvenile idiopathic arthritis, juvenile dermatomyositis, systemic lupus erythematosus, and those requiring chronic glucocorticoids may benefit from routine screening of bone health. Most commonly used assessment tools are laboratory testing including serum 25-OH-vitamin D measurement and bone mineral density measurement by a variety of methods, dual-energy X-ray absorptiometry as the most widely used. Early disease control, use of steroid-sparing medications such as disease-modifying anti-rheumatic drugs and biologics, supplemental vitamin D and calcium, and promotion of weight-bearing physical activities can help optimize bone health. Additional treatment options for osteoporosis such as bisphosphonates are still controversial in children with chronic rheumatic diseases, especially those with decreased bone density without fragility fractures. This article reviews common risk factors leading to compromised bone health in children with chronic rheumatic diseases and discusses the general approach to prevention and treatment of bone fragility.

The associations between serum 25-hydroxyvitamin D level and the risk of total fracture and hip fracture

In this meta-analysis, we evaluated the association between serum 25-hydroxyvitamin D (25(OH) vitamin D) level and the risk of total fractures and hip fractures. Low serum 25(OH) vitamin D level is associated with an increased risk of total and hip fractures.

INTRODUCTION

Data on the association between serum 25(OH) vitamin D level and the risk of fractures are conflicting. This study aimed to provide a summary of prospective cohort or nested case-control studies on the association between serum 25(OH) vitamin D level and the risk of total fractures and hip fractures.

METHODS

We identified relevant studies by searching the PubMed, EMBASE, and OVID databases from their inception to June 1, 2016. We included published prospective cohort or nested case-control studies evaluating the associations of serum 25(OH) vitamin D level with the fracture risk. Two reviewers abstracted the data independently. Relative risks (RRs) with 95% confidence intervals (CIs) were derived throughout the whole analysis.

RESULTS

Sixteen prospective cohort studies and three nested case-control studies were included. We found that low serum 25(OH) vitamin D level was significantly associated with the risk of total fractures (RR 1.25, 95% CI 1.06-1.43; I ² = 31.3%, p for heterogeneity = 0.15) and hip fractures (RR 1.48, 95% CI 1.29-1.68; I ² = 0%, p for heterogeneity = 0.51). The hip fracture risk was increased by 40% for each SD decrease in serum 25(OH) vitamin D level (RR 1.40, 95% CI 1.20-1.61; I ² = 0%, p for heterogeneity = 0.51). The per SD decrease in serum 25(OH) vitamin D level was not associated with the increased risk of total fractures (RR 1.14, 95% CI 0.93-1.35; I ² = 63.2%, p for heterogeneity = 0.04).

CONCLUSIONS

Our study suggests that low serum 25(OH) vitamin D level is associated with increased risks of total and hip fractures. In the analyzed studies, the per SD decrease in serum 25(OH) vitamin D level was associated with the hip fracture risk but not with the total fracture risk.

Associations of total and free 25OHD and 1,25(OH)2D with serum markers of inflammation in older men

Vitamin D is hypothesized to suppress inflammation. We tested total and free vitamin D metabolites and their association with inflammatory markers. Interleukin-6 levels were lower with higher 25-hydroxyvitamin D. 1,25-dihydroxyvitamin D and free 25OHD associations mirrored those of 25OHD. However, associations for the two metabolites diverged for tumor necrosis factor alpha (TNF-α) soluble receptors.

INTRODUCTION

Vitamin D is hypothesized to suppress inflammation, and circulating 25-hydroxyvitamin D (25OHD) and inflammatory markers are inversely correlated. However, total serum 25OHD may not be the best indicator of biologically active vitamin D.

METHODS

We tested serum total 25OHD, total 1,25(OH)2D, vitamin D binding protein (DBP), and estimated free 25OHD and free 1,25(OH)2D associations with inflammatory markers serum interleukin-6 (IL-6), TNF-α and their soluble receptors, interleukin-10 (IL-10), and C-reactive protein (CRP) as continuous outcomes and the presence of ≥2 inflammatory markers in the highest quartile as a dichotomous outcome, in a random subcohort of 679 men in the Osteoporotic Fractures in Men (MrOS) study.

RESULTS

IL-6 was lower in men with higher 25OHD (-0.23 μg/mL per standard deviation (SD) increase in 25OHD, 95 % confidence intervals (CI) -0.07 to -0.38 μg/mL) and with higher 1,25(OH)2D (-0.20 μg/mL, 95 % CI -0.0004 to -0.39 μg/mL); free D associations were slightly stronger. 25OHD and DBP, but not 1,25(OH)2D, were independently associated with IL-6. TNF-α soluble receptors were inversely associated with 1,25(OH)2D but positively associated with 25OHD, and each had independent effects. The strongest association with ≥2 inflammatory markers in the highest quartile was for free 1,25(OH)2D (odds ratios (OR) 0.70, 95 % CI 0.54 to 0.89 per SD increase in free 1,25(OH)2D).

CONCLUSIONS

Associations of 1,25(OH)2D and free 25OHD with IL-6 mirrored those of 25OHD, suggesting that 1,25(OH)2D and free D do not improve upon 25OHD in population-based IL-6 studies. However, associations for the two metabolites diverged for TNF-α soluble receptor, warranting examination of both metabolites in studies of TNF-α and its antagonists.

Osteoporosis in men: findings from the Osteoporotic Fractures in Men Study (MrOS)

The lifespan of men is increasing and this is associated with an increased prevalence of osteoporosis in men. Osteoporosis increases the risk of bone fracture. Fractures are associated with increased disability and mortality, and public health problems. We review here the study of osteoporosis in men as obtained from a longitudinal cohort of community-based older men, the Osteoporotic Fractures in Men Study (MrOS).