Effect of Vitamin B12 and Folic Acid Supplementation on Bone Mineral Density and Quantitative Ultrasound Parameters in Older People with an Elevated Plasma Homocysteine Level: B-PROOF, a Randomized Controlled Trial

Role of vitamins beyond vitamin D3 in bone health and osteoporosis (Review)

The objective of the present review was to summarize the molecular mechanisms associated with the effects of the vitamins A, C, E and K, and group B vitamins on bone and their potential roles in the development of osteoporosis. Epidemiological findings have demonstrated an association between vitamin deficiency and a higher risk of developing osteoporosis; vitamins are positively related to bone health upon their intake at the physiological range. Excessive vitamin intake can also adversely affect bone formation, as clearly demonstrated for vitamin A. Vitamins E (tocopherols and tocotrienols), K2 (menaquinones 4 and 7) and C have also been shown to promote osteoblast development through bone morphogenetic protein (BMP)/Smad and Wnt/β‑catenin signaling, as well as the TGFβ/Smad pathway (α‑tocopherol). Vitamin A metabolite (all‑trans retinoic acid) exerts both inhibitory and stimulatory effects on BMP‑ and Wnt/β‑catenin‑mediated osteogenesis at the nanomolar and micromolar range, respectively. Certain vitamins significantly reduce receptor activator of nuclear factor kappa‑B ligand (RANKL) production and RANKL/RANK signaling, while increasing the level of osteoprotegerin (OPG), thus reducing the RANKL/OPG ratio and exerting anti‑osteoclastogenic effects. Ascorbic acid can both promote and inhibit RANKL signaling, being essential for osteoclastogenesis. Vitamin K2 has also been shown to prevent vascular calcification by activating matrix Gla protein through its carboxylation. Therefore, the maintenance of a physiological intake of vitamins should be considered as a nutritional strategy for the prevention of osteoporosis.

Associations of dietary oxidative balance score with femur osteoporosis in postmenopausal women: data from the National Health and Nutrition Examination Survey

We used data from the NHANES to explore associations of DOBS with femur BMD and osteoporosis in postmenopausal women. We found that DOBS was positively associated with femur BMD and negatively associated with the risk of osteoporosis in postmenopausal women.

PURPOSE

The study aimed to investigate the relationship between dietary oxidative balance score (DOBS) and the risk of osteoporosis in American postmenopausal women.

METHODS

A total of 3043 participants were included in this study. The linear relationship between DOBS and femur BMD was evaluated using a weighted multivariate linear regression model. The association between DOBS and the risk of osteoporosis was assessed using a weighted logistic regression model, with odds ratios (ORs) and 95% confidence intervals (CIs) calculated. Moreover, the relationship was further characterized through smooth curve fitting (SCF) and weighted generalized additive model (GAM) analysis.

RESULTS

After adjusting for all covariates, the weighted multivariable linear regression models showed a positive correlation between DOBS and femur BMD. Moreover, the weighted logistic regression model demonstrated that compared to the first tertile of DOBS, the highest tertile of DOBS was significantly associated with a lower risk of osteoporosis, with ORs of 0.418 (95% CI, 0.334, 0.522) for individuals under the age of 70 and 0.632 (95% CI, 0.506, 0.790) for individuals aged 70 or above. Similar trends were also observed in SCF and GAM models.

CONCLUSION

The present study indicated that postmenopausal women with a higher DOBS have a lower risk of femur osteoporosis. This finding may highlight the potential protective role of an antioxidant-rich diet for the bones of the postmenopausal population. Moreover, DOBS may also be a valuable tool in identifying individuals with osteoporosis. Screening and early intervention for osteoporosis may be essential for postmenopausal women with low DOBS.

Inferring causal effects of homocysteine and B-vitamin concentrations on bone mineral density and fractures: Mendelian randomization analyses

Objectives

In the progress of bone metabolism, homocysteine (Hcy) and B vitamins play substantial roles. However, the causal associations of homocysteine, B-vitamin concentrations with bone mineral density (BMD), and fractures remain unclear. Therefore, we employed a two-sample Mendelian randomization (MR) design to infer the causal effects of Hcy and B vitamins on BMD and fractures.

Methods

We selected instrumental variables from large genome-wide association studies (GWASs). Specifically, the exposures mainly included Hcy (sample size: 44,147), vitamin B12 (sample size: 45,576), folate (sample size: 37,465), and vitamin B6 (sample size: 1,864). The outcome variables included total body BMD (sample size: 66,628), heel BMD (sample size: 142,487), femoral neck BMD (sample size: 32,735), lumbar spine BMD (sample size: 28,498), and forearm BMD (sample size: 8143). Additionally, the total body BMD in several age strata was also included. Furthermore, the fractures of the forearm, femoral neck, lumbar spine, heel corresponding with the BMD regions, and femoral neck and lumbar spine BMD in men and women, separately, were added as additional outcomes. Two-sample MR approaches were utilized in this study. Inverse variance weighting (IVW) was adopted as the main analysis. MR-PRESSO, MR-Egger, the weighted median estimate, and multivariable MR were performed as sensitivity methods.

Results

In the main analysis, Hcy concentrations have an inverse association with heel BMD (Beta = 0.046, 95% confidence interval (CI) -0.073 to -0.019, P = 9.59E-04) per SD unit. In addition, for one SD increase of vitamin B12, the total body BMD decreased 0.083 unit (95%CI -0.126 to -0.040, P = 1.65E-04). The trend was more obvious in age over 45 years (Beta = -0.135, 95%CI -0.203-0.067, P = 9.86E-05 for age 45-60; Beta = -0.074, 95%CI -0.141 to -0.007, P = 0.031 for age over 60 years). No association of B vitamins and Hcy levels with the risk of fractures and femoral neck and lumbar spine BMD in men and women was found in this study. Other sensitivity MR methods elucidated consistent results.

Conclusions

Our findings indicated that there exist the inversely causal effects of Hcy and vitamin B12 on BMD in certain body sites and age strata. These give novel clues for intervening bone-related diseases in public health and nutrition.

Bone Health in Patients with Dyslipidemias: An Underestimated Aspect

Beyond being aging-related diseases, atherosclerosis and osteoporosis share common pathogenetic pathways implicated in bone and vascular mineralization. However, the contributory role of dyslipidemia in this interplay is less documented. The purpose of this narrative review is to provide epidemiological evidence regarding the prevalence of bone disease (osteoporosis, fracture risk) in patients with dyslipidemias and to discuss potential common pathophysiological mechanisms linking osteoporosis and atherosclerosis. The effect of hypolipidemic therapy on bone metabolism is also discussed. Despite the high data heterogeneity and the variable quality of studies, dyslipidemia, mainly elevated total and low-density lipoprotein cholesterol concentrations, is associated with low bone mass and increased fracture risk. This effect may be mediated directly by the increased oxidative stress and systemic inflammation associated with dyslipidemia, leading to increased osteoclastic activity and reduced bone formation. Moreover, factors such as estrogen, vitamin D and K deficiency, and increased concentrations of parathyroid hormone, homocysteine and lipid oxidation products, can also contribute. Regarding the effect of hypolipidemic medications on bone metabolism, statins may slightly increase BMD and reduce fracture risk, although the evidence is not robust, as it is for omega-3 fatty acids. No evidence exists for the effects of ezetimibe, fibrates, and niacin. In any case, more prospective studies are needed further to elucidate the association between lipids and bone strength.

Nutrition, Physical Activity, and Dietary Supplementation to Prevent Bone Mineral Density Loss: A Food Pyramid

Bone is a nutritionally modulated tissue. Given this background, aim of this review is to evaluate the latest data regarding ideal dietary approach in order to reduce bone mineral density loss and to construct a food pyramid that allows osteopenia/osteoporosis patients to easily figure out what to eat. The pyramid shows that carbohydrates should be consumed every day (3 portions of whole grains), together with fruits and vegetables (5 portions; orange-colored fruits and vegetables and green leafy vegetables are to be preferred), light yogurt (125 mL), skim milk (200 mL,) extra virgin olive oil (almost 20 mg/day), and calcium water (almost 1 l/day); weekly portions should include fish (4 portions), white meat (3 portions), legumes (2 portions), eggs (2 portions), cheeses (2 portions), and red or processed meats (once/week). At the top of the pyramid, there are two pennants: one green means that osteopenia/osteoporosis subjects need some personalized supplementation (if daily requirements cannot be satisfied through diet, calcium, vitamin D, boron, omega 3, and isoflavones supplementation could be an effective strategy with a great benefit/cost ratio), and one red means that there are some foods that are banned (salt, sugar, inorganic phosphate additives). Finally, three to four times per week of 30-40 min of aerobic and resistance exercises must be performed.

Does Folic Acid Protect Patients with Inflammatory Bowel Disease from Complications?

Folic acid, referred to as vitamin B9, is a water-soluble substance, which participates in the synthesis of nucleic acids, amino acids, and proteins. Similarly to B12 and B6, vitamin B9 is involved in the metabolism of homocysteine, which is associated with the MTHFR gene. The human body is not able to synthesize folic acid; thus, it must be supplemented with diet. The most common consequence of folic acid deficiency is anemia; however, some studies have also demonstrated the correlation between low bone mineral density, hyperhomocysteinemia, and folic acid deficiency. Patients with inflammatory bowel disease (IBD) frequently suffer from malabsorption and avoid certain products, such as fresh fruits and vegetables, which constitute the main sources of vitamin B9. Additionally, the use of sulfasalazine by patients may result in folic acid deficiency. Therefore, IBD patients present a higher risk of folic acid deficiency and require particular supervision with regard to anemia and osteoporosis prevention, which are common consequences of IBD.

Nutrients with anabolic/anticatabolic, antioxidant, and anti-inflammatory properties: Targeting the biological mechanisms of aging to support musculoskeletal health

Old age is associated with declines in bone density and muscle mass and function, which predisposes to mobility disability, falls, and fractures. Poor nutritional status, a risk factor for several age-related pathologies, becomes prevalent in old age and contributes to the structural and functional changes of the musculoskeletal system that increases the risk of osteoporosis, sarcopenia, osteosarcopenia, and physical frailty. The biological mechanisms underpinning these pathologies often overlap and include loss of proteostasis, impaired redox functioning, and chronic low-grade inflammation. Thus, provision of nutrients with anabolic/anticatabolic, antioxidant, and anti-inflammatory properties may be an effective strategy to offset these age-related pathologies. We searched PUBMED for pre-clinical and clinical work examining the effects of nutrients with a combined effect on muscle and bone. This review summarizes recent evidence on the mechanisms of action and potential clinical use of nutrients that concomitantly improve muscle and bone health in older persons.

Adequate intake and supplementation of B vitamins, in particular folic acid, can play a protective role in bone health

In vitro and animal model studies have shown that B vitamins (VB) deficiency have negative consequences on bone, as a result of direct or mediated activity of hyperhomocysteinemia. However, there are still no precise indications regarding a possible VB role in order to maintain bone health. So, the aim of this narrative review was to consider the state of the art on correlation between VB dietary intake, blood levels and supplementation and bone health (bone mineral density (BMD), bone turnover markers and fractures risk) in humans. This review included 29 eligible studies. Considering VB blood levels, the 14 studies considered have shown that low serum folate can be a factor risk for reduced BMD and fractures in elderly, particularly women; no independent association was found for other VB. Studies that evaluate relationship between VB dietary intake and BMD are only 2; one, conducted on 1869 women, demonstrated a positive effect of folate intake on BMD, another demonstrated a dose-dependent inverse relationship between vitamin B6 dietary intake and risk of hip fracture, but only for 35298 female participants. Regarding the relationship between BV supplementation and bone health (9 studies with only VB and 4 with other nutrients), all studies that considered patients with hyperhomocysteinemia or with low folate blood levels, are in agreement in demonstrating that folate supplementation (500mcg-5mg) is useful in improving BMD. In conclusion, a request for folate and homocysteine blood levels in elderly patients with osteopenia/osteoporosis is mandatory. For patients with hyperhomocysteinemia or with low folate blood levels, folate supplementation (500mcg-5mg) is crucial.

The association of homocysteine, folate, vitamin B12, and vitamin B6 with fracture incidence in older adults: a systematic review and meta-analysis

Background

Diverse conclusions have been drawn regarding the association of homocysteine (HCY) deficiency and supplements of B vitamins with fracture incidence in older adults. The aim of this meta-analysis was to investigate the association of HCY and B vitamins (folate, vitamin B12, and B6) with fracture incidence in older adults and whether supplements of B vitamins reduce the risk of fracture.

Methods

The PubMed, Embase, and Cochrane library databases were systematically searched from their inception dates to 1 July 2019 to identify relevant published articles. Meta-analysis was performed to pool hazard ratios (HRs) or risk ratios (RRs) and 95% confidence intervals (CIs) using a random effects model.

Results

A total of 28 studies fulfilled the inclusion criteria. High serum HCY was an independent risk factor for fractures in older persons (HR =1.25, 95% CI: 1.12 to 1.40), but only at the highest quartile level (>15 µmol/L) (HR =1.71, 95% CI: 1.37 to 2.12), rather than the second and third quartile. Multiple sensitivity and subgroup analyses supported the consistency and stability of this result. A severe deficiency of folate, instead of vitamin B12 and B6, was found to increase the risk of fracture in older adults (HR =1.46, 95% CI: 1.06 to 2.02; 1.24, 95% CI: 0.79 to 1.95; 1.36, 95% CI: 0.90 to 2.06, respectively). For the interventional effect, there was no significant association of combined folate and vitamin B12, combined folate, vitamin B12 and B6, or single vitamin B6 supplementation with the decrease of fracture risk.

Discussion

This meta-analysis revealed that significantly elevated serum level of HCY is positively associated with fracture incidence in older adults, yet the necessity and threshold for intervention by B vitamins require further large-scale high-quality clinical trials to validate.

PROSPERO identifier

CRD42019122586.

Genetic variants modify the associations of concentrations of methylmalonic acid, vitamin B-12, vitamin B-6, and folate with bone mineral density

BACKGROUND

Elevated plasma homocysteine has been found to be associated with an increased risk of osteoporosis, especially hip and vertebral fractures. The plasma concentration of homocysteine is dependent on the activities of several B vitamin-dependent enzymes, such as methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), methionine synthase reductase (MTRR), and cystathionine β-synthase (CBS).

OBJECTIVES

We investigated whether genetic variants in some of the genes involved in 1 carbon metabolism modify the association of B vitamin-related measures with bone mineral density (BMD) and strength.

METHODS

We measured several B vitamins and biomarkers in participants of the Framingham Offspring Study, and performed analyses of methylmalonic acid (MMA) continuously and <210 nmol/L; pyridoxal-5'-phosphate; vitamin B-12 continuously and ≥258 pmol/L; and folate. The outcomes of interest included areal and volumetric BMD, measured by DXA and quantitative computed tomography (QCT), respectively. We evaluated associations between the bone measures and interactions of single nucleotide polymorphism with a B vitamin or biomarker in Framingham participants (n = 4310 for DXA and n = 3127 for QCT). For analysis of DXA, we validated the association results in the B-PROOF cohort (n = 1072). Bonferroni-corrected locus-wide significant thresholds were defined to account for multiple testing.

RESULTS

The interactions between rs2274976 and vitamin B-12 and rs34671784 and MMA <210 nmol/L were associated with lumbar spine BMD, and the interaction between rs6586281 and vitamin B-12 ≥258 pmol/L was associated with femoral neck BMD. For QCT-derived traits, 62 interactions between genetic variants and B vitamins and biomarkers were identified.

CONCLUSIONS

Some genetic variants in the 1-carbon methylation pathway modify the association of B vitamin and biomarker concentrations with bone density and strength.  These interactions require further replication and functional validation for a mechanistic understanding of the role of the 1-carbon metabolism pathway on BMD and risks of fracture.

Oxidative balance score and risk of osteoporosis among postmenopausal Iranian women

To our knowledge, this is the first study to examine the association of oxidative balance score (OBS) and risk of osteoporosis. Findings suggest that a predominance of anti- over pro-oxidant exposures, as reflected by a higher OBS, is associated with lower risk of lumbar spine osteoporosis among postmenopausal Iranian women.

PURPOSE

The oxidative balance score (OBS) is a combined measure of pro- and anti-oxidant exposure status, with a higher OBS indicating a predominance of anti- over pro-oxidant exposures. We aimed to examine the potential association of OBS and risk of osteoporosis among postmenopausal Iranian women, hypothesizing that a higher OBS is associated with lower risk of postmenopausal osteoporosis.

METHODS

This cross-sectional study was conducted among 151 postmenopausal Iranian women aged 50-85 y. Bone mineral density (BMD) at lumbar spine and femoral neck was measured by dual-energy X-ray absorptiometry, and osteoporosis was defined using the WHO criteria as a BMD T-score of ≤ - 2.5 standard deviations. The OBS was calculated by combining information from 17 a-priori selected pro- and anti-oxidant components classified in the following four categories: non-dietary pro-oxidants (i.e., obesity and smoking); non-dietary anti-oxidants (i.e., physical activity); dietary pro-oxidants (i.e., saturated fatty acid, poly-unsaturated fatty acid, and iron); and dietary anti-oxidants (i.e., fiber, vitamin E, folate, vitamin C, alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, lycopene, zinc, and selenium).

RESULTS

After controlling for several potential covariates in the multivariable-adjusted binary logistic regression analysis, subjects in the highest tertile of OBS had a lower risk of lumbar spine osteoporosis than those in the lowest tertile (odds ratio = 0.14; 95% confidence interval, 0.04-0.45; p = 0.001). The OBS was not associated with risk of femoral neck osteoporosis.

CONCLUSION

Findings suggest that a predominance of anti- over pro-oxidant exposures, as indicated by a higher OBS, is associated with lower risk of lumbar spine osteoporosis among postmenopausal Iranian women.

Cobalamin Deficiency in the Elderly

Older people are at risk for cobalamin (vitamin B₁₂) deficiency because of a number of common disorders (e.g., autoimmune gastritis) and drugs (e.g., antacids) that may alter its absorption and utilization. The prevalence of cobalamin deficiency increases with age, resulting, particularly elevated, in frail and institutionalized subjects. At variance with common sense, the diagnosis is far from simple. It requires a high degree of suspicion, due to heterogeneity and non-specificity of the signs and symptoms, ranging from macrocytosis (with or without anemia) to neuropsychiatric manifestations, that characterize several other aging-related disorders, like hematological malignancies, diabetes, hypothyroidism or vasculopathy. Furthermore, the detection of low levels of serum vitamin B₁₂ appears poorly sensitive and specific. Other biomarkers, like serum homocysteine or methylmalonic acid, have improved the diagnostic possibilities but are expensive, not widely available, and may be influenced by some confounders (e.g., folate deficiency, or chronic renal failure). Early recognition and treatment are crucial since a proportion of patients develop severe complications, such as bone marrow failure and irreversible neurological impairment. High-dose oral treatment has proven to be as effective as the parenteral route, even in subjects with malabsorption, ensuring the complete resolution in the majority of cases. In this review, we trace the essential role of cobalamin in humans, the possible causes and impact of deficiency, the diagnostic challenges and the therapeutic options, between old and emerging concepts, with a particular focus on the elderly.

Hyperhomocysteinemia is Associated with Inflammation, Bone Resorption, Vitamin B12 and Folate Deficiency and MTHFR C677T Polymorphism in Postmenopausal Women with Decreased Bone Mineral Density

Osteoporosis is an age-related bone disease, affecting mainly postmenopausal women, characterized by decreased bone mineral density (BMD) and consequent risk of fractures. Homocysteine (Hcy), a sulfur-aminoacid whose serum level is regulated by methylenetrahydrofolate reductase (MTHFR) activity and vitamin B12 and folate as cofactors, is a risk factor for inflammatory diseases. Literature data concerning the link between Hcy and osteoporosis are still debated. The aim of our study was to assess the relationship among Hcy and BMD, inflammation, vitamin status and bone turnover in postmenopausal osteoporosis. In 252 postmenopausal women, BMD was measured by dual-energy X-ray absorptiometry (DXA). In addition to serum Hcy, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and bone turnover markers (bone alkaline phosphatase-BAP, osteocalcin-OC, C-terminal telopeptide of type I collagen (CTX), vitamin deficiencies and MTHFR-C677T polymorphism were evaluated. Hcy, inflammation, bone resorption markers and prevalence of C677T polymorphism were higher, whereas vitamin D, B12, folate, and bone formation markers were lower in women with decreased BMD compared to those with normal BMD. Our results suggest a significant association between Hcy, BMD and inflammation in postmenopausal osteoporosis. The regulation of Hcy overproduction and the modulation of the inflammatory substrate could represent additional therapeutic approaches for osteoporosis prevention.

Nutrients in the Prevention of Osteoporosis in Patients with Inflammatory Bowel Diseases

The chronic character of inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis, results in various complications. One of them is osteoporosis, manifested by low bone mineral density, which leads to an increased risk of fractures. The aetiology of low bone mineral density is multifactorial and includes both diet and nutritional status. Calcium and vitamin D are the most often discussed nutrients with regard to bone mineral density. Moreover, vitamins A, K, C, B12; folic acid; calcium; phosphorus; magnesium; sodium; zinc; copper; and selenium are also involved in the formation of bone mass. Patients suffering from inflammatory bowel diseases frequently consume inadequate amounts of the aforementioned minerals and vitamins or their absorption is disturbed, resulting innutritional deficiency and an increased risk of osteoporosis. Thus, nutritional guidelines for inflammatory bowel disease patients should comprise information concerning the prevention of osteoporosis.

Homocysteine: Its Possible Emerging Role in At-Risk Population Groups

Increased plasma homocysteine is a risk factor for several pathological disorders. The present review focused on the role of homocysteine (Hcy) in different population groups, especially in risk conditions (pregnancy, infancy, old age), and on its relevance as a marker or etiological factor of the diseases in these age groups, focusing on the nutritional treatment of elevated Hcy levels. In pregnancy, Hcy levels were investigated in relation to the increased risk of adverse pregnancy outcomes such as small size for gestational age at birth, preeclampsia, recurrent abortions, low birth weight, or intrauterine growth restriction. In pediatric populations, Hcy levels are important not only for cardiovascular disease, obesity, and renal disease, but the most interesting evidence concerns study of elevated levels of Hcy in autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). Finally, a focus on the principal pathologies of the elderly (cardiovascular and neurodegenerative disease, osteoporosis and physical function) is presented. The metabolism of Hcy is influenced by B vitamins, and Hcy-lowering vitamin treatments have been proposed. However, clinical trials have not reached a consensus about the effectiveness of vitamin supplementation on the reduction of Hcy levels and improvement of pathological condition, especially in elderly patients with overt pathologies, suggesting that other dietary and non-dietary factors are involved in high Hcy levels. The importance of novel experimental designs focusing on intra-individual variability as a complement to the typical case-control experimental designs and the study of interactions between different factors it should be emphasized.

Higher concentration of serum C-terminal cross-linking telopeptide of type I collagen is positively related with inflammatory factors in postmenopausal women with H-type hypertension and osteoporosis

OBJECTIVE

To investigate the changes of inflammatory factors and bone metabolism markers in postmenopausal women with H-type hypertension and to assess the relationship between them.

METHODS

Postmenopausal women who were diagnosed with osteoporosis were selected as observation objects. Participants were divided into three groups: only osteoporosis group (osteoporosis group), hypertension combined with osteoporosis group (hypertension group), and H-type hypertension combined with osteoporosis group (H-type hypertension group). The changes in bone mineral density and bone metabolic markers (osteocalcin [OC], procollagen type I N-terminal propeptide (PINP), and C-terminal cross-linking telopeptide of type I collagen [CTX]) and inflammatory factors (interleukin-6 [IL-6] and tumor necrosis factor-α [TNF-α]) were compared among three groups.

RESULTS

In the hypertension group and the H-type hypertension group, the bone mineral density of the lumbar spine (0.647 ± 0.038 vs 0.638 ± 0.034 vs 0.668 ± 0.047, P < 0.05) and the femoral neck (0.567 ± 0.047 vs 0.552 ± 0.053 vs 0.618 ± 0.059, P < 0.05) was significantly lower than that in the osteoporosis group. The concentrations of CTX (266.61 ± 64.65 vs 293.09 ± 72.34 vs 235.48 ± 62.85, P < 0.05), IL-6 (44.36 ± 6.45 vs 48.05 ± 8.04 vs 39.06 ± 7.95, P < 0.05) and TNF-α (30.53 ± 6.28 vs 34.52 ± 7.15 vs 28.66 ± 6.19, P < 0.01) in the hypertension group and in the H-type hypertension group were significantly higher than those in the osteoporosis group. The concentrations of OC (30.59 ± 6.43 vs 27.10 ± 6.51, P < 0.05) and PINP (36.36 ± 6.16 vs 33.16 ± 6.77, P < 0.05) in the H-type hypertension group were increased dramatically. The concentration of CTX was positively correlated with the concentration of IL-6 (r = 0.587, P < 0.01) and TNF-α (r = 0.474, P < 0.01) and negatively related with the concentration of OC (r = -0.591, P < 0.01) and PINP (r = -0.646, P < 0.01) and the bone mineral density of the lumbar spine (r = -0.470, P < 0.01) and the femoral neck (r = -0.509, P < 0.01).

CONCLUSION

Higher concentration of serum CTX is found in postmenopausal women with H-type hypertension, which is positively correlated with inflammatory factors. Besides, H-type hypertension could further enhance the activity of osteoclasts and increase the expressions of inflammatory factors, resulting in the aggravation of osteoporosis.

Biomarkers of Nutrition for Development (BOND): Vitamin B-12 Review

This report on vitamin B-12 (B12) is part of the Biomarkers of Nutrition for Development (BOND) Project, which provides state-of-the art information and advice on the selection, use, and interpretation of biomarkers of nutrient exposure, status, and function. As with the other 5 reports in this series, which focused on iodine, folate, zinc, iron, and vitamin A, this B12 report was developed with the assistance of an expert panel (BOND B12 EP) and other experts who provided information during a consultation. The experts reviewed the existing literature in depth in order to consolidate existing relevant information on the biology of B12, including known and possible effects of insufficiency, and available and potential biomarkers of status. Unlike the situation for the other 5 nutrients reviewed during the BOND project, there has been relatively little previous attention paid to B12 status and its biomarkers, so this report is a landmark in terms of the consolidation and interpretation of the available information on B12 nutrition. Historically, most focus has been on diagnosis and treatment of clinical symptoms of B12 deficiency, which result primarily from pernicious anemia or strict vegetarianism. More recently, we have become aware of the high prevalence of B12 insufficiency in populations consuming low amounts of animal-source foods, which can be detected with ≥1 serum biomarker but presents the new challenge of identifying functional consequences that may require public health interventions.

Homocysteine-lowering interventions for preventing cardiovascular events

BACKGROUND

Cardiovascular disease, which includes coronary artery disease, stroke and peripheral vascular disease, is a leading cause of death worldwide. Homocysteine is an amino acid with biological functions in methionine metabolism. A postulated risk factor for cardiovascular disease is an elevated circulating total homocysteine level. The impact of homocysteine-lowering interventions, given to patients in the form of vitamins B6, B9 or B12 supplements, on cardiovascular events has been investigated. This is an update of a review previously published in 2009, 2013, and 2015.

OBJECTIVES

To determine whether homocysteine-lowering interventions, provided to patients with and without pre-existing cardiovascular disease are effective in preventing cardiovascular events, as well as reducing all-cause mortality, and to evaluate their safety.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2017, Issue 5), MEDLINE (1946 to 1 June 2017), Embase (1980 to 2017 week 22) and LILACS (1986 to 1 June 2017). We also searched Web of Science (1970 to 1 June 2017). We handsearched the reference lists of included papers. We also contacted researchers in the field. There was no language restriction in the search.

SELECTION CRITERIA

We included randomised controlled trials assessing the effects of homocysteine-lowering interventions for preventing cardiovascular events with a follow-up period of one year or longer. We considered myocardial infarction and stroke as the primary outcomes. We excluded studies in patients with end-stage renal disease.

DATA COLLECTION AND ANALYSIS

We performed study selection, 'Risk of bias' assessment and data extraction in duplicate. We estimated risk ratios (RR) for dichotomous outcomes. We calculated the number needed to treat for an additional beneficial outcome (NNTB). We measured statistical heterogeneity using the I2 statistic. We used a random-effects model. We conducted trial sequential analyses, Bayes factor, and fragility indices where appropriate.

MAIN RESULTS

In this third update, we identified three new randomised controlled trials, for a total of 15 randomised controlled trials involving 71,422 participants. Nine trials (60%) had low risk of bias, length of follow-up ranged from one to 7.3 years. Compared with placebo, there were no differences in effects of homocysteine-lowering interventions on myocardial infarction (homocysteine-lowering = 7.1% versus placebo = 6.0%; RR 1.02, 95% confidence interval (CI) 0.95 to 1.10, I2 = 0%, 12 trials; N = 46,699; Bayes factor 1.04, high-quality evidence), death from any cause (homocysteine-lowering = 11.7% versus placebo = 12.3%, RR 1.01, 95% CI 0.96 to 1.06, I2 = 0%, 11 trials, N = 44,817; Bayes factor = 1.05, high-quality evidence), or serious adverse events (homocysteine-lowering = 8.3% versus comparator = 8.5%, RR 1.07, 95% CI 1.00 to 1.14, I2 = 0%, eight trials, N = 35,788; high-quality evidence). Compared with placebo, homocysteine-lowering interventions were associated with reduced stroke outcome (homocysteine-lowering = 4.3% versus comparator = 5.1%, RR 0.90, 95% CI 0.82 to 0.99, I2 = 8%, 10 trials, N = 44,224; high-quality evidence). Compared with low doses, there were uncertain effects of high doses of homocysteine-lowering interventions on stroke (high = 10.8% versus low = 11.2%, RR 0.90, 95% CI 0.66 to 1.22, I2 = 72%, two trials, N = 3929; very low-quality evidence).We found no evidence of publication bias.

AUTHORS' CONCLUSIONS

In this third update of the Cochrane review, there were no differences in effects of homocysteine-lowering interventions in the form of supplements of vitamins B6, B9 or B12 given alone or in combination comparing with placebo on myocardial infarction, death from any cause or adverse events. In terms of stroke, this review found a small difference in effect favouring to homocysteine-lowering interventions in the form of supplements of vitamins B6, B9 or B12 given alone or in combination comparing with placebo.There were uncertain effects of enalapril plus folic acid compared with enalapril on stroke; approximately 143 (95% CI 85 to 428) people would need to be treated for 5.4 years to prevent 1 stroke, this evidence emerged from one mega-trial.Trial sequential analyses showed that additional trials are unlikely to increase the certainty about the findings of this issue regarding homocysteine-lowering interventions versus placebo. There is a need for additional trials comparing homocysteine-lowering interventions combined with antihypertensive medication versus antihypertensive medication, and homocysteine-lowering interventions at high doses versus homocysteine-lowering interventions at low doses. Potential trials should be large and co-operative.

Bilateral atypical femur fractures without bisphosphonate exposure

Atypical femur fractures have common radiographic features that set them apart from more typical higher-energy subtrochanteric femur fractures. They are noncomminuted, transverse fractures with medial spiking of the femoral cortex and increased lateral cortical thickness. These fractures have been associated in the literature with the use of bisphosphonate medications. This case describes bilateral atypical femur fractures in a patient with a medical history devoid of bisphosphonate use. We present his history, co-morbidities, and subsequent treatment. From this case, we call attention to bisphosphonate use as not the only cause of subtrochanteric femur fractures with atypical features and highlight that some patients may sustain these injuries even bilaterally without use of the medications. In addition, it is important to identify this fracture type and obtain imaging of the contralateral femur to facilitate prophylactic treatment if needed.

Causes, Consequences and Public Health Implications of Low B-Vitamin Status in Ageing

The potential protective roles of folate and the metabolically related B-vitamins (vitamins B12, B6 and riboflavin) in diseases of ageing are of increasing research interest. The most common cause of folate and riboflavin deficiencies in older people is low dietary intake, whereas low B12 status is primarily associated with food-bound malabsorption, while sub-optimal vitamin B6 status is attributed to increased requirements in ageing. Observational evidence links low status of folate and the related B-vitamins (and/or elevated concentrations of homocysteine) with a higher risk of degenerative diseases including cardiovascular disease (CVD), cognitive dysfunction and osteoporosis. Deficient or low status of these B-vitamins alone or in combination with genetic polymorphisms, including the common MTHFR 677 C → T polymorphism, could contribute to greater disease risk in ageing by causing perturbations in one carbon metabolism. Moreover, interventions with the relevant B-vitamins to optimise status may have beneficial effects in preventing degenerative diseases. The precise mechanisms are unknown but many have been proposed involving the role of folate and the related B-vitamins as co-factors for one-carbon transfer reactions, which are fundamental for DNA and RNA biosynthesis and the maintenance of methylation reactions. This review will examine the evidence linking folate and related B-vitamins with health and disease in ageing, associated mechanisms and public health implications.

Bone Mineral Density in Sjögren Syndrome Patients with and Without Distal Renal Tubular Acidosis

Primary Sjögren's syndrome (pSS) can be complicated by distal renal tubular acidosis (dRTA), which may contribute to low bone mineral density (BMD). Our objective was to evaluate BMD in pSS patients with and without dRTA as compared with healthy controls. BMD of lumbar spine (LS) and femoral neck (FN) was measured in 54 pSS patients and 162 healthy age- and sex-matched controls by dual-energy X-ray absorptiometry (DXA). dRTA was defined as inability to reach urinary pH <5.3 after an ammonium chloride (NH4Cl) test. LS- and FN-BMD were significantly higher in pSS patients compared with controls (1.18 ± 0.21 g/cm(2) for patients vs. 1.10 ± 0.18 g/cm(2) for controls, P = 0.008 and 0.9 ± 0.16 g/cm(2) for patients vs. 0.85 ± 0.13 g/cm(2) for controls, P = 0.009, respectively). After adjustment for BMI and smoking, the LS- and FN-BMD remained significantly higher. Patients with dRTA (N = 15) did not have a significantly different LS- and FN-BMD compared with those without dRTA (N = 39) after adjustment for BMI, age, and gender. Thirty-seven (69 %) pSS patients were using hydroxychloroquine (HCQ). Unexpectedly, pSS patients had a significantly higher LS- and FN-BMD compared with healthy controls. Patients with dRTA had similar BMD compared with patients without dRTA. We postulate that an explanation for the higher BMD in pSS patients may be the frequent use of HCQ.

A Randomized Controlled Trial to Examine the Effect of 2-Year Vitamin B12 and Folic Acid Supplementation on Physical Performance, Strength, and Falling: Additional Findings from the B-PROOF Study

Elevated homocysteine concentrations are associated with a decline in physical function in elderly persons. Homocysteine-lowering therapy may slow down this decline. This study aimed to examine the effect of a 2-year intervention of vitamin B12 and folic acid supplementation on physical performance, handgrip strength, and risk of falling in elderly subjects in a double-blind, randomized placebo-controlled trial. Participants aged ≥65 years with elevated plasma homocysteine concentrations [12-50 µmol/L (n = 2919)] were randomly assigned to daily supplementation of 500 µg vitamin B12, 400 µg folic acid, and 600 IU vitamin D3, or to placebo with 600 IU vitamin D3. Physical performance (range 0-12) and handgrip strength (kg) were measured at baseline and after 2 years. Falls were reported prospectively on a research calendar. Intention-to-treat (primary) and per-protocol (secondary) analyses were performed. Physical performance level and handgrip strength significantly decreased during the follow-up period, but this decline did not differ between groups. Moreover, time to first fall was not significantly different (HR: 1.0, 95% CI 0.9-1.2). Secondary analyses on a per-protocol base identified an interaction effect with age on physical performance. In addition, the treatment was associated with higher follow-up scores on the walking test (cumulative OR: 1.3, 95% CI 1.1-1.5). Two-year supplementation of vitamin B12 and folic acid was neither effective in reducing the age-related decline in physical performance and handgrip strength, nor in the prevention of falling in elderly persons. Despite the overall null-effect, the results provide indications for a positive effect of the intervention on gait, as well as on physical performance among compliant persons >80 years. These effects should be further tested in future studies.

Arterial stiffness is not associated with bone parameters in an elderly hyperhomocysteinemic population

Several studies have observed positive associations between bone disease and cardiovascular disease. A potential common pathway is hyperhomocysteinemia; however, to date, there is a lack of data regarding hyperhomocysteinemic populations. Therefore, we examined both cross-sectionally and longitudinally, whether there is an association between bone parameters and arterial stiffness in a hyperhomocysteinemic population, and investigated the potential common role of homocysteine (hcy) level on these associations. Cross-sectional and longitudinal data of the B-PROOF study were used (n = 519). At both baseline and 2-year follow-up we determined bone measures-incident fractures and history of fractures, bone-mineral density (BMD) and quantitative ultrasound (QUS) measurement. We also measured arterial stiffness parameters at baseline-pulse wave velocity, augmentation index and aortic pulse pressure levels with applanation tonometry. Linear regression analysis was used to examine these associations and we tested for potential interaction of hcy level. The mean age of the study population was 72.3 years and 44.3 % were female. Both cross-sectionally and longitudinally there was no association between arterial stiffness measures and BMD or QUS measurements or with incident fractures (n = 16) within the 2-3 years of follow-up. Hcy level did not modify the associations and adjustment for hcy did not change the results. Arterial stiffness was not associated with bone parameters and fractures, and hcy neither acted as a pleiotropic factor nor as a mediator. The potential association between bone and arterial stiffness is therefore not likely to be driven by hyperhomocysteinemia.

Life-course approach to nutrition

This narrative review summarizes the role that nutrition plays in the development and maintenance of a healthy skeleton throughout the life-course. Nutrition has a significant influence on bone health throughout the life cycle. This narrative review summarizes current knowledge and guidance pertaining to the development and maintenance of a healthy skeleton. The primary objectives proposed for good bone health at the various stages of life are the following: Children and adolescents: achieve genetic potential for peak bone mass Adults: avoid premature bone loss and maintain a healthy skeleton Seniors: prevention and treatment of osteoporosis Findings from cohort studies, randomized controlled trials, systematic reviews and meta-analyses, in addition to current dietary guidelines, are summarized with the intention of providing clear nutritional guidance for these populations and pregnant women.

B-vitamin status and bone mineral density and risk of lumbar osteoporosis in older females in the United States

BACKGROUND

Previous data suggest that elevated serum total homocysteine (tHcy) may be a risk factor for bone fracture and osteoporosis. Nutritional causes of elevated tHcy are suboptimal B-vitamin status. To our knowledge, this is the first nationally representative report on the relation of B vitamins and bone health from a population with folic acid fortification.

OBJECTIVE

The purpose of this analysis was to examine the relation between B-vitamin status biomarkers and bone mineral density (BMD), risk of osteoporosis, and biomarkers of bone turnover.

DESIGN

We examined the relation of tHcy, methylmalonic acid (MMA), and serum/red blood cell folate and total-body and lumbar spine BMD in women aged ≥50 y participating in the NHANES 1999-2004 (n = 2806), a nationally representative cross-sectional survey. These are the only years with concurrent measurement of tHcy and whole-body dual-energy X-ray absorptiometry. We also examined B-vitamin biomarkers relative to bone turnover markers, bone alkaline phosphatase, and urinary N-terminal cross-linked telopeptide of type I collagen in a 1999-2002 subset with available data (n = 1813).

RESULTS

In comparison with optimal concentrations, women with elevated tHcy were older with lower serum vitamin B-12, red blood cell folate, and dietary micronutrient intakes and had significantly higher mean ± SE markers of bone turnover (bone alkaline phosphatase: 15.8 ± 0.59 compared with 14.0 ± 0.25 μg/L; urinary N-terminal cross-linked telopeptide of type I collagen: 48.2 ± 2.9 compared with 38.9 ± 0.90 nmol bone collagen equivalents per mmol creatinine/L). Elevated MMA (OR: 1.88; 95% CI: 1.10, 3.18) and tHcy (OR: 2.17; 95% CI: 1.14, 4.15) were related to increased risk of lumbar osteoporosis. When examined as a continuous variable, tHcy was negatively associated, serum folates were positively associated, and MMA and vitamin B-12 were not significantly associated with lumbar and total-body BMD.

CONCLUSION

In this nationally representative population of older US women with high exposure to B vitamins through food fortification and dietary supplements, only elevated tHcy and MMA were independently associated with risk of lumbar spine osteoporosis.