1-alpha-Hydroxyvitamin D3 treatment decreases bone turnover and modulates calcium-regulating hormones in early postmenopausal women

Vitamin D Supplementation and Its Impact on Mortality and Cardiovascular Outcomes: Systematic Review and Meta-Analysis of 80 Randomized Clinical Trials

BACKGROUND

The impact of vitamin D supplementation on cardiovascular outcomes and mortality risk reduction remains unclear due to conflicting study findings.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs), published between 1983 and 2022, that reported the effect of vitamin D supplementation in adults versus placebo or no treatment on all-cause mortality (ACM), cardiovascular mortality (CVM), non-cardiovascular mortality (non-CVM), and cardiovascular morbidities. Only studies with a follow-up period longer than one year were included. The primary outcomes were ACM and CVM. Secondary outcomes were non-CVM, myocardial infarction, stroke, heart failure, and major or extended adverse cardiovascular events. Subgroup analyses were performed according to low-, fair- and good-quality RCTs.

RESULTS

Eighty RCTs were assessed, including 82,210 participants receiving vitamin D supplementation and 80,921 receiving placebo or no treatment. The participants' mean (SD) age was 66.1 (11.2) years, and 68.6% were female. Vitamin D supplementation was associated with a lower risk of ACM (OR: 0.95 [95%CI 0.91-0.99] p = 0.013), was close to statistical significance for a lower risk of non-CVM (OR: 0.94 [95%CI 0.87-1.00] p = 0.055), and was not statistically associated with a lower risk of any cardiovascular morbi-mortality outcome. Meta-analysis of low-quality RCTs showed no association with cardiovascular or non-cardiovascular morbi-mortality outcomes.

CONCLUSIONS

The emerging results of our meta-analysis present evidence that vitamin D supplementation appears to decrease the risk of ACM (especially convincing in the fair- and good-quality RCTs), while not showing a decrease in the specific cardiovascular morbidity and mortality risk. Thus, we conclude that further research is warranted in this area, with well-planned and executed studies as the basis for more robust recommendations.

Plain vitamin D or active vitamin D in the treatment of osteoporosis: where do we stand today?

Osteoporosis is a major cause of morbidity and mortality worldwide and its prevention in order to avert fractures was considered of great importance in maintaining well-being and independence among the elderly. Strategies for osteoporosis prevention are well delineated, but research shows that the treatment options offered today could still be improved. The role of plain vitamin D (cholecalciferol) in bone health and the prevention of osteoporosis are well documented; however, as a treatment for osteoporosis, either with or without calcium, it has been shown to be ineffective. This is due in part to the strong negative feedback mechanisms in place in vitamin D-replete patients. However, other factors linked directly to ageing such as oestrogen depletion, reduced kidney or liver function may also be involved in reducing the body's capability to activate plain vitamin efficiently. This is why active vitamin D analogues such as alfacalcidol, 1-α-(OH)D3, are of clinical interest. Alfacalcidol requires only one hydroxylation reaction to become active 1,25-(OH)2-vitamin D3, and the 25-hydroxylase catalyzing this reaction is found in the liver and also interestingly in osteoblasts suggesting a local effect. Registered for use in postmenopausal osteoporosis, in most countries worldwide, alfacalcidol has also shown efficacy in glucocorticoid-induced and male osteoporosis. The present review provides compelling evidence for the efficacy of this compound in the treatment of osteoporosis and prevention of fractures both in monotherapy and when combined with other osteoporotic drugs where additive effects are clear. The safety profile of alfacalcidol is shown to be highly acceptable and it is considered less likely to induce hypercalcaemia than another more widely used analogue, calcitriol. Therefore, it remains unclear as to why alfacalcidol is not more widely used in clinical practice.

Impact of calcium, vitamin D, vitamin K, oestrogen, isoflavone and exercise on bone mineral density for osteoporosis prevention in postmenopausal women: a network meta-analysis

The aim of this network meta-analysis is to compare bone mineral density (BMD) changes among different osteoporosis prevention interventions in postmenopausal women. We searched MEDLINE, Embase and Cochrane Library from inception to 24 February 2019. Included studies were randomised controlled trials (RCT) comparing the effects of different treatments on BMD in postmenopausal women. Studies were independently screened by six authors in three pairs. Data were extracted independently by two authors and synthesised using Bayesian random-effects network meta-analysis. The results were summarised as mean difference in BMD and surface under the cumulative ranking (SUCRA) of different interventions. A total of ninety RCT (10 777 participants) were included. Ca, vitamin D, vitamin K, oestrogen, exercise, Ca + vitamin D, vitamin D + vitamin K and vitamin D + oestrogen were associated with significantly beneficial effects relative to no treatment or placebo for lumbar spine (LS). For femoral neck (FN), Ca, exercise and vitamin D + oestrogen were associated with significantly beneficial intervention effects relative to no treatment. Ranking probabilities indicated that oestrogen + vitamin D is the best strategy in LS, with a SUCRA of 97·29 % (mean difference: +0·072 g/cm2 compared with no treatment, 95 % credible interval (CrI) 0·045, 0·100 g/cm2), and Ca + exercise is the best strategy in FN, with a SUCRA of 79·71 % (mean difference: +0·029 g/cm2 compared with placebo, 95 % CrI –0·00093, 0·060 g/cm2). In conclusion, in postmenopausal women, many interventions are valuable for improving BMD in LS and FN. Different intervention combinations can affect BMD at different sites diversely.

Association of vitamin D3 with alveolar bone regeneration in dogs

Designed sockets prepared on the mandibles of nine Beagle dogs were divided into three groups: Calcitriol +Alloplast, Alloplast and Empty. Five of the nine dogs received Vit.D₃ and calcium supplement (Vit.D/Ca group), while the other four dogs without supplements were assigned to Non-Vit.D/Ca group. After 4 weeks, the extent of vertical ridge resorption (VRR), bone density (density), new bone formation (NBF) and implant stability quotient (ISQ) were measured. Following systemic Vit.D/Ca administration, the Empty subgroup showed significant differences from the Calcitriol + Alloplast subgroup on variants NBF/Density/VRR and the Alloplast subgroup on items NBF/Density/ISQ/VRR. Alternatively, the Calcitriol + Alloplast subgroup revealed higher values of NBF/Density/ISQ (P < 0.001) and a lower VRR value (P = 0.001) than the Alloplast subgroup. Although there were no significant differences in NBF (P = 0.349), density (P = 0.796), ISQ (P = 0.577) and VRR (0.979) comparisons on alloplast treatment between the Vit.D/Ca and Non-Vit.D/Ca groups, local application with Calcitriol + Alloplast demonstrated better NBF/Density/ISQ (P = 0.02 to <0.001) effects than which of Alloplast subgroups. Consequently, the results showed that both systemic and local vitamin D₃ treatment might accelerate bone regeneration in dogs. Within the using dose, systemic vitamin D₃ treatment displayed a superior stimulating effect than local vitamin D₃ application did.

Vitamin D and vitamin D analogues for preventing fractures in post-menopausal women and older men

BACKGROUND

Vitamin D and related compounds have been used to prevent osteoporotic fractures in older people. This is the third update of a Cochrane review first published in 1996.

OBJECTIVES

To determine the effects of vitamin D or related compounds, with or without calcium, for preventing fractures in post-menopausal women and older men.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (to December 2012), the Cochrane Central Register of Controlled Trials (2012, Issue 12), MEDLINE (1966 to November Week 3 2012), EMBASE (1980 to 2012 Week 50), CINAHL (1982 to December 2012), BIOSIS (1985 to 3 January 2013), Current Controlled Trials (December 2012) and reference lists of articles.

SELECTION CRITERIA

Randomised or quasi-randomised trials that compared vitamin D or related compounds, alone or with calcium, against placebo, no intervention or calcium alone, and that reported fracture outcomes in older people. The primary outcome was hip fracture.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial risk of selection bias and aspects of methodological quality, and extracted data. Data were pooled, where possible, using the fixed-effect model, or the random-effects model when heterogeneity between studies appeared substantial.

MAIN RESULTS

We included 53 trials with a total of 91,791 participants. Thirty-one trials, with sample sizes ranging from 70 to 36,282 participants, examined vitamin D (including 25-hydroxy vitamin D) with or without calcium in the prevention of fractures in community, nursing home or hospital inpatient populations. Twelve of these 31 trials had participants with a mean or median age of 80 years or over.Another group of 22 smaller trials examined calcitriol or alfacalcidol (1-alphahydroxyvitamin D3), mostly with participants who had established osteoporosis. These trials were carried out in the setting of institutional referral clinics or hospitals.In the assessment of risk of bias for random sequence generation, 21 trials (40%) were deemed to be at low risk, 28 trials (53%) at unclear risk and four trials at high risk (8%). For allocation concealment, 22 trials were at low risk (42%), 29 trials were at unclear risk (55%) and two trials were at high risk (4%).There is high quality evidence that vitamin D alone, in the formats and doses tested, is unlikely to be effective in preventing hip fracture (11 trials, 27,693 participants; risk ratio (RR) 1.12, 95% confidence intervals (CI) 0.98 to 1.29) or any new fracture (15 trials, 28,271 participants; RR 1.03, 95% CI 0.96 to 1.11).There is high quality evidence that vitamin D plus calcium results in a small reduction in hip fracture risk (nine trials, 49,853 participants; RR 0.84, 95% confidence interval (CI) 0.74 to 0.96; P value 0.01). In low-risk populations (residents in the community: with an estimated eight hip fractures per 1000 per year), this equates to one fewer hip fracture per 1000 older adults per year (95% CI 0 to 2). In high risk populations (residents in institutions: with an estimated 54 hip fractures per 1000 per year), this equates to nine fewer hip fractures per 1000 older adults per year (95% CI 2 to 14). There is high quality evidence that vitamin D plus calcium is associated with a statistically significant reduction in incidence of new non-vertebral fractures. However, there is only moderate quality evidence of an absence of a statistically significant preventive effect on clinical vertebral fractures. There is high quality evidence that vitamin D plus calcium reduces the risk of any type of fracture (10 trials, 49,976 participants; RR 0.95, 95% CI 0.90 to 0.99).In terms of the results for adverse effects: mortality was not adversely affected by either vitamin D or vitamin D plus calcium supplementation (29 trials, 71,032 participants, RR 0.97, 95% CI 0.93 to 1.01). Hypercalcaemia, which was usually mild (2.6 to 2.8 mmol/L), was more common in people receiving vitamin D or an analogue, with or without calcium (21 trials, 17,124 participants, RR 2.28, 95% CI 1.57 to 3.31), especially for calcitriol (four trials, 988 participants, RR 4.41, 95% CI 2.14 to 9.09), than in people receiving placebo or control. There was also a small increased risk of gastrointestinal symptoms (15 trials, 47,761 participants, RR 1.04, 95% CI 1.00 to 1.08), especially for calcium plus vitamin D (four trials, 40,524 participants, RR 1.05, 95% CI 1.01 to 1.09), and a significant increase in renal disease (11 trials, 46,548 participants, RR 1.16, 95% CI 1.02 to 1.33). Other systematic reviews have found an increased association of myocardial infarction with supplemental calcium; and evidence of increased myocardial infarction and stroke, but decreased cancer, with supplemental calcium plus vitamin D, without an overall effect on mortality.

AUTHORS' CONCLUSIONS

Vitamin D alone is unlikely to prevent fractures in the doses and formulations tested so far in older people. Supplements of vitamin D and calcium may prevent hip or any type of fracture. There was a small but significant increase in gastrointestinal symptoms and renal disease associated with vitamin D and calcium. This review found that there was no increased risk of death from taking calcium and vitamin D.

Evaluating hormonal mechanisms of vitamin D receptor agonist therapy in diabetic kidney disease: the VALIDATE-D study

BACKGROUND

Insufficient vitamin D status and increased renin-angiotensin system (RAS) activity have been associated with renal-vascular disease and nephropathy in diabetes. Accumulating evidence indicates that vitamin D receptor (VDR) activation lowers unfavorable RAS activity; however, more human intervention studies evaluating whether this mechanism could influence diabetic kidney disease are needed. We previously reported that both vitamin D levels and genetic variation at the VDR predict human RAS activity, and that vitamin D therapy can lower RAS activity in non-diabetics. The VALIDATE-D study is a randomized, placebo-controlled, intervention study designed to extend these findings by evaluating whether direct VDR activation in diabetes lowers circulating and local renal-vascular tissue RAS activity (Aims 1 and 2) in a manner similar to the action of ACE inhibitors (Aim 3).

METHODS/DESIGN

Forty subjects with type 2 diabetes, microalbuminuria, and without chronic kidney disease will be recruited to undergo detailed assessment of the RAS before and after randomization to calcitriol 0.75 mcg/day or placebo. Primary analyses will evaluate whether calcitriol therapy reduces circulating and renal-vascular tissue-RAS activity in comparison to placebo. All subjects will thereafter be treated with lisinopril and followed for 3.5 months to evaluate whether combination therapy (calcitriol + lisinopril vs. placebo + lisinopril) additively or synergistically improves renal-vascular function, and lowers proteinuria.

DISCUSSION

The VALIDATE-D study is the first human intervention study to evaluate whether direct VDR activation can lower the human RAS in diabetes, compared to the effect of an ACE inhibitor, and whether this mechanism can translate to clinically relevant endpoints for diabetic kidney disease. The outcomes of VALIDATE-D will have major implications for the recommendation of vitamin D supplementation for the primary prevention of kidney complications in diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01635062.

The potential effects of cholecalciferol on bone regeneration in dogs

OBJECTIVES

The aim of this investigation was to evaluate the potential effects of the systemically delivered combination of calcium supplementation and cholecalciferol and of the locally applied biphasic calcium alloplast on the surgically produced alveolar sockets at the early healing stage in a dog model.

MATERIALS AND METHODS

The mandibular pre-molars of nine Beagle dogs were extracted first. Three months later, four standardized sockets with a 4 mm in diameter and 6 mm deep cylinder were created bilaterally at healed extraction sites. The sockets on one side were grafted with biphasic calcium phosphate alloplast, whereas the defects on the other side were left un-grafted. The dogs were then randomly divided into two groups; five dogs received oral calcium and cholecalciferol combination (Vit.D/Ca) and were assigned to the test group (Vit.D/Ca Group). The other four dogs without Vit.D/Ca supplement were distributed to the control group (Non-Vit.D/Ca Group). The bone density (Density) and the implant stability quotient (ISQ) at prepared sites were measured 4 weeks later. The drawn bone cores were examined by a histomorphometric analysis for measurement of new bone formation (NBF). The amount of vertical ridge resorption (VRR) was evaluated.

RESULTS

The Vit.D/Ca-treated subjects revealed significantly more NBF (P < 0.05), higher bone density (P < 0.05) and significantly less vertical ridge reduction (P < 0.05) in the healing sockets than those without Vit.D/Ca treatment. The non-grafted sockets demonstrated significantly more NBF (P < 0.05), higher bone density (P < 0.05), better ISQ value (P < 0.05) and more vertical ridge reduction (P < 0.05) than those in the grafted sockets. There was no significant difference between the serum data determined before and 4 weeks after experiment in Vit.D/Ca Group or Non-Vit.D/Ca Group. However, the changed value (post-op vs. pre-op) between the two groups was significant in the serum level of phosphate and parathyroid hormone (P = 0.05).

CONCLUSION

The results of the present study indicated that the examined calcium phosphate alloplast may perform a function in alveolar ridge preservation while reducing the potential of NBF potential in the healing extraction socket. Also, the combination of calcium supplementation and cholecalciferol may have systemic effects on accelerating bone regeneration.

A nonsecosteroidal vitamin D receptor ligand with improved therapeutic window of bone efficacy over hypercalcemia

Vitamin D(3) analogues were shown to be beneficial for osteoporosis and other indications, but their narrow therapeutic window between efficacy and hypercalcemia has limited their clinical utility. A nonsecosteroidal, tissue-selective, orally bioavailable, vitamin D receptor (VDR) ligand was ascertained to be efficacious in bone while having modest calcemic effects in vivo. This compound (VDRM2) potently induced Retinoid X Receptor alpha (RXR)-VDR heterodimerization (EC(50) = 7.1 +/- 1.6 nM) and induced osteocalcin promoter activity (EC(50) = 1.9 +/- 1.6 nM). VDRM2 was less potent in inducing Ca(2+) channel transient receptor potential cation channel, subfamily V, member 6 (TRPV6) expression (EC(50) = 37 +/- 12 nM). VDRM2 then was evaluated in osteopenic ovariectomized (OVX) rats and shown to dose-dependently restore vertebral bone mineral density (BMD) from OVX to sham levels at 0.08 microg/kg per day. Hypercalcemia was observed at a dose of 4.6 microg/kg per day of VDRM2, suggesting a safety margin of 57 [90% confidence interval (CI) 35-91]. 1alpha,25-dihydroxyvitamin D(3) [1alpha,25(OH)(2)D], ED71, and alfacalcidol restored BMD at 0.030, 0.0055, and 0.046 microg/kg per day, respectively, whereas hypercalcemia was observed at 0.22, 0.027, and 0.23 microg/kg per day, indicating a safety margin of 7.3, 4.9, and 5.0, respectively (90% CIs 4.1-13, 3.2-7.7, and 3.5-6.7, respectively). Histomorphometry showed that VDRM2 increased cortical bone area and stimulated the periosteal bone-formation rate relative to OVX at doses below the hypercalcemic dose. By contrast, ED71 increased the periosteal bone-formation rate only above the hypercalcemic dose. VDRM2 suppressed eroded surface on trabecular bone surfaces at normal serum calcium dosage levels, suggesting dual anabolic and antiresorptive activity. In summary, vitamin D analogues were more potent than VDRM2, but VDRM2 had a greater safety margin, suggesting possible therapeutic potential.

The bone mass density in postmenopausal women using hormonal replacement therapy in relation to polymorphism in vitamin D receptor and estrogen receptor genes

The aims of the study were as follows: (1) To identify the differences in spinal body mass density (BMD) in relation to polymorphism in vitamin D receptor (VDR) and estrogen receptor-alpha (ERalpha) genes in untreated women with postmenopausal osteoporosis. (2) To assess the efficacy of treatment in women with postmenopausal osteoporosis in relation to polymorphism in VDR and ERalpha genes. (3) To find the estradiol concentration necessary to protect bone tissue in patients with a given polymorphism in VDR and ERalpha genes.

METHODS

The study included 44 postmenopausal women with primary osteoporosis who used cyclic hormonal replacement therapy (HRT) for a year. The polymorphism of ERalpha and VDR genes were evaluated. We also determined the age, body mass index and spinal BMD before and after 12 months of administration the HRT.

RESULTS

We found a significant spinal BMD increase, what is connected with ERalpha genotype and both VDR and ERalpha genes. There is no such a correlation observed in polymorphism of VDR gene.

CONCLUSIONS

(1) There is no relationship between VDR and ERalpha genes polymorphism and the stage of osteoporosis related to the spinal BMD value before treatment. (2) The XX, PP or Bb markers or only X, P, B alleles are connected with a significant decrease of treatment efficacy. (3) Estradiol serum concentration before and during HRT is not dependent on the polymorphism of VDR and ERalpha genes.

Vitamin D and vitamin D analogues for preventing fractures associated with involutional and post-menopausal osteoporosis

BACKGROUND

Vitamin D and related compounds have been used to prevent osteoporotic fractures in older people.

OBJECTIVES

To determine the effects of vitamin D or related compounds, with or without calcium, for preventing fractures in older people.

SEARCH STRATEGY

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials (The Cochrane Library 2007, Issue 3), MEDLINE, EMBASE, CINAHL, and reference lists of articles. Most recent search: October 2007.

SELECTION CRITERIA

Randomised or quasi-randomised trials comparing vitamin D or related compounds, alone or with calcium, against placebo, no intervention, or calcium alone, reporting fracture outcomes in older people.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality, and extracted data. Data were pooled, where admissible, using the fixed-effect model, or random-effects model if heterogeneity between studies appeared high.

MAIN RESULTS

Forty-five trials were included. Vitamin D alone appears unlikely to be effective in preventing hip fracture (nine trials, 24,749 participants, RR 1.15, 95% CI 0.99 to 1.33), vertebral fracture (five trials, 9138 participants, RR 0.90, 95% CI 0.42 to 1.92) or any new fracture (10 trials, 25,016 participants, RR 1.01, 95% CI 0.93 to 1.09).Vitamin D with calcium reduces hip fractures (eight trials, 46,658 participants, RR 0.84, 95% CI 0.73 to 0.96). Although subgroup analysis by residential status showed a significant reduction in hip fractures in people in institutional care, the difference between this and the community-dwelling subgroup was not significant (P = 0.15).Overall hypercalcaemia is significantly more common in people receiving vitamin D or an analogue, with or without calcium (18 trials, 11,346 participants, RR 2.35, 95% CI 1.59 to 3.47); this is especially true of calcitriol (four trials, 988 participants, RR 4.41, 95% CI 2.14 to 9.09). There is a modest increase in gastrointestinal symptoms (11 trials, 47,042 participants, RR 1.04, 95% CI 1.00 to 1.08, P = 0.04) and a small but significant increase in renal disease (11 trials, 46,537 participants, RR 1.16, 95% CI 1.02 to 1.33).

AUTHORS' CONCLUSIONS

Frail older people confined to institutions may sustain fewer hip fractures if given vitamin D with calcium. Vitamin D alone is unlikely to prevent fracture. Overall there is a small but significant increase in gastrointestinal symptoms and renal disease associated with vitamin D or its analogues. Calcitriol is associated with an increased incidence of hypercalcaemia.

Effect of vitamin K2 treatment on carboxylation of osteocalcin in early postmenopausal women

OBJECTIVE

We examined the serum level of undercarboxylated osteocalcin (uc OC), which is a sensitive marker of vitamin K status, and levels of bone turnover markers in early postmenopausal women receiving vitamin K2 treatment with or without vitamin D3.

METHODS

Thirty-four postmenopausal women with a mean age of 53 years whose bone mineral density (BMD) was less than 0.809 g/cm2 (osteopenia and osteoporosis) were treated with vitamin K2 or with a combination of vitamin K2 and vitamin D3. Seventeen women received daily oral administration of 45 mg vitamin K2 and 17 women received daily oral administration of 45 mg vitamin K2 plus 0.75 microg 1alpha-hydroxyvitamin D3. Serum levels of uc OC, intact osteocalcin (OC) and bone alkaline phosphatase (BAP), urinary deoxypyridinoline (DPD) levels and BMD at the lumbar spine were measured before and at 1 and 2 years after the start of treatment.

RESULTS

Serum uc OC levels in women treated with vitamin K2 alone and with both vitamin K2 and vitamin D3 decreased significantly (p < 0.05). Serum levels of intact OC and BAP in women treated with vitamin K2 did not show significant changes, while those in women who received the combined treatment decreased significantly (p < 0.05). On the other hand, urinary DPD level in women treated with vitamin K2 did not change, while that in women who received the combined treatment tended to decrease (p < 0.1).

CONCLUSION

Serum uc OC levels in early postmenopausal women who received vitamin K2 decreased due to carboxylation of uc OC. Combined treatment with vitamin K2 and vitamin D3 may be effective for sustaining BMD in early postmenopausal women whose bone turnovers are highly activated.

Effects of alfacalcidol alone or in combination with elcatonin on incidence of osteoporotic vertebral fractures in postmenopausal women with spondylosis

Osteoporosis and spondylosis often occur simultaneously. However, there are no previous reports about the effects of osteoporosis medication on incidence of vertebral fractures in people with spondylosis. In this study, we conducted a retrospective investigation of the effects of alfacalcidol alone or in combination with elcatonin on incidence of osteoporotic vertebral fractures in women with spondylosis. The present subjects were 101 postmenopausal women with osteoporosis aged >60 years, divided into three groups: D group (n = 45), treated for >5 years with alfacalcidol; D+ECT group (n = 26), treated for >5 years with alfacalcidol plus elcatonin; control group (n = 30), who received no medications for >5 years. Over the 5-year treatment period, bone mineral density (BMD) of the lumbar spine and proximal femur did not significantly change in the D and D+ECT groups, but they significantly decreased in the control group (P < 0.05). The number of incident vertebral fractures per patient was significantly higher in the control group (2.9) than in the D group (1.2) and D+ECT group (1.5) (P < 0.01). There was no significant difference in BMD or incident vertebral fractures between the D and D+ECT groups. In all three groups, the number of incident vertebral fractures positively correlated with the number of prevalent vertebral fractures (0.303 </= r </= 0.434), and negatively correlated with baseline BMD (-0.703 </= r </= -0.326) and the osteophyte score representing the degree of spondylosis (-0.769 </= r </= -0.365). Further multiple regression analysis revealed that the medication (D or D+ECT, P < 0.001) and the osteophyte score (P < 0.001) were the most significant contributors for the number of incident vertebral fractures. In conclusion, elcatonin had no additive effects on BMD or prevention of vertebral fractures in postmenopausal women receiving alfacalcidol. Presence of spondylosis (indicated by a high osteophyte score) appears to have an effect on prevention of vertebral fractures.

Effect of Vitamin D and Calcium on Periodontitis

The anthropological record indicates that we are exposed to considerably less ultraviolet radiation (required for the synthesis of vitamin D) and consume considerably less calcium than did our early ancestors. Most U.S. citizens have calcium intakes and serum levels of vitamin D far below recommended values. This is despite there having been extensive evidence that optimal calcium and vitamin D intakes not only benefit our postcranial bone health but also have many other health benefits. Numerous articles indicate that vitamin D and calcium deficiencies result in bone loss and increased inflammation, which are well recognized symptoms of periodontal disease. For more than 40 years, investigators have suggested that calcium intake may be associated with alveolar bone resorption, and more recently there have been a number of studies in which investigators have suggested that calcium and vitamin D may benefit periodontal health, and it has been suggested that calcium deficiency may be a risk factor for periodontal disease. There has not, however, been a vitamin-D-calcium-periodontitis clinical trial in which randomization and masking were carefully controlled, the periodontal disease status of patients known, periodontal disease measures were the primary outcomes, and levels of intake optimized to produce maximal effects. Such research might demonstrate that calcium and vitamin D are important adjuncts to standard treatments for preventing and treating periodontal disease.

Vitamin D and vitamin D analogues for preventing fractures associated with involutional and post-menopausal osteoporosis

BACKGROUND

Vitamin D and related compounds have been used to prevent fractures.

OBJECTIVES

To determine the effects of vitamin D or analogues, with or without calcium, in the prevention of fractures in older people.

SEARCH STRATEGY

We searched the Cochrane Bone, Joint and Muscle Trauma Group trials register, the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 1, 2005), MEDLINE, EMBASE, CINAHL, and reference lists of articles. Most recent search: March 2005.

SELECTION CRITERIA

Randomised or quasi-randomised trials comparing vitamin D or an analogue, alone or with calcium, against placebo, no intervention, or calcium, reporting fracture outcomes, in older people.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality, and extracted data. Data were pooled, where admissible, using the fixed-effect model, or random-effects model if the relative risks were heterogeneous.

MAIN RESULTS

Vitamin D alone showed no statistically significant effect on hip fracture (seven trials, 18,668 participants, RR 1.17, 95% CI 0.98 to 1.41), vertebral fracture (four trials, 5698 participants, RR (random effects) 1.13, 95% CI 0.50 to 2.55) or any new fracture (eight trials, 18,903 participants, RR 0.99, 95% CI 0.91 to 1.09). Vitamin D with calcium marginally reduced hip fractures (seven trials, 10,376 participants, RR 0.81, 95% CI 0.68 to 0.96), non-vertebral fractures (seven trials, 10,376 participants, RR 0.87, 95% CI 0.78 to 0.97), but there was no evidence of effect of vitamin D with calcium on vertebral fractures. The effect appeared to be restricted to those living in institutional care. Hypercalcaemia was more common when vitamin D or its analogues was given compared with placebo or calcium (14 trials, 8035 participants, RR 2.38, 95% CI 1.52 to 3.71). The risk was particularly high with calcitriol (three trials, 742 participants, RR 14.94, 95% CI 2.95 to 75.61). There was no evidence that vitamin D increased gastro-intestinal symptoms (seven trials, 10,188 participants, RR (random effects) 1.03, 95% CI 0.79 to 1.36) or renal disease (nine trials, 10,107 participants, RR 0.80, 95% CI 0.34 to 1.87).

AUTHORS' CONCLUSIONS

Frail older people confined to institutions may sustain fewer hip and other non-vertebral fractures if given vitamin D with calcium supplements. Effectiveness of vitamin D alone in fracture prevention is unclear. There is no evidence of advantage of analogues of vitamin D compared with vitamin D. Calcitriol may be associated with an increased incidence of adverse effects. Dose, frequency, and route of administration of vitamin D in older people require further investigation.

D-hormone analog alfacalcidol: an update on its role in post-menopausal osteoporosis and rheumatoid arthritis management

Alfacalcidol (1-alpha-hydroxyvitamin D3) is a non-endogenous analog of vitamin D which can bypass the renal and intestinal regulatory mechanisms that control the production of calcitriol (1,25-hydroxyvitamin D3, the active form of vitamin D, D-Hormone). Alfacalcidol may be metabolized into calcitriol with a limited risk of hypercalcemia. Alfacalcidol and calcitriol have been evaluated in animal and human studies assessing their effects on bone mineral density and fracture rates. More recently, they have been shown to produce beneficial effects in muscle, immune system, and autoimmune diseases, including rheumatoid arthritis. This paper discusses the therapeutic efficacy of alfacalcidol in reports in which it has been proposed as an interesting alternative to vitamin D or calcitriol. Some recent findings about general metabolism and regulation of vitamin D and its analogs are discussed. The biological and clinical effects of alfacalcidol in post-menopausal osteoporosis are reviewed, followed by critical appraisal of its efficacy in preventing bone loss and falls in the elderly. The last two sections discuss the role of D analogs in regulating the immune system, with particular regard to rheumatoid arthritis. The main results of this review show that alfacalcidol may have a wider range of therapeutic applicability, beyond simply restricting it to patients in hemodialysis or peritoneal dialysis with high serum levels of intact PTH.

Human races and pharmacogenomics of effective bone treatments

Osteoporosis and its complications represent one of the most important causes of morbidity and mortality around the world. Moreover, its management presents an important economic problem. Although osteoporosis is a worldwide health problem, there are many differences in ethnic groups regarding disease morbidity and drug treatment efficacy. This review analyzed clinical response data of two major osteoporotic treatments (vitamin D and estrogens) regarding four major human races (Asian, Caucasian, Hispanic and Negroid). From clinical studies, Asians seem to be more vitamin-D-sensitive while Caucasians appear more estrogen-sensitive than other human races. Different drug responses may be related to allelic variants in their signaling genes such as those for the vitamin D receptor (VDR) and estrogen receptor-alpha (ER alpha). Some polymorphisms of VDR and ER alpha loci appear to be genetic determinants of osteoporotic risk: ApaI-BsmI-TaqI, FokI variants and poly(A) repeats in VDR; PvuII-XbaI variants and (TA) repeats in ER alpha. Also, because of specific ethnic allele distributions, these VDR and ER alpha polymorphisms may be involved in race differences of osteoporosis treatment responses. Future studies and preventive strategies for the management of osteoporosis need to take into account these racial and genetic factors.

Effects of alendronate on bone mineral density and bone metabolic markers in postmenopausal asthmatic women treated with inhaled corticosteroids

We have recently shown that long-term use of inhaled corticosteroids decreases bone mineral density (BMD) of the lumbar spine in postmenopausal asthmatic women. The present study aimed to evaluate the efficacy of alendronate in comparison with that of alfacalcidol (1-alpha-hydroxyvitamin D(3)) for the treatment of BMD reduction in postmenopausal asthmatic patients who had inhaled corticosteroid therapy without regular use of systemic corticosteroids. Twenty-eight postmenopausal asthmatic patients with BMD T score of -1.0 or less were randomized to receive alendronate (5 mg/d) or alfacalcidol (1 microg/d). Bone mineral density was determined at baseline and 12 months after the treatment, and biochemical markers of bone metabolism were measured at baseline and after 6 and 12 months of treatment. The mean (+/-SD) BMD values at the lumbar spine, the total hip, and the Ward's triangle significantly increased by 4.9 +/- 4.5% (P = .0005), 2.4 +/- 2.2% (P = .0005), and 3.6 +/- 5.2% (P = .02) at 12 months in the alendronate group, whereas the corresponding values did not significantly change in the alfacalcidol group. In the alendronate group, urinary N-telopeptide (NTx), serum osteocalcin, and serum alkaline phosphatase concentrations significantly decreased, and serum intact parathyroid (PTH) level significantly increased, from baseline at both 6 and 12 months. In the alfacalcidol group, urinary NTx showed modest but significant decrease, although the extent of the change was smaller than that in the alendronate group. We concluded that alendronate was effective to improve reduced BMD in postmenopausal asthmatic patients on inhaled corticosteroid therapy through the mechanism of inhibiting bone resorption.

Estrogen and/or Calcium Plus Vitamin D Increase Mandibular Bone Mass

BACKGROUND

We have previously reported that estrogen/hormone replacement therapy (E/HRT) has beneficial effects on oral bone density over 3 years and that calcium and vitamin D supplementation has a lesser effect. Here we report on mandibular bone mass for 49 women (of the original cohort of 135) who continued in an additional 2-year, open-label extension.

METHODS

Postmenopausal women were randomly assigned to receive calcium and vitamin D plus E/HRT, or calcium and vitamin D only. Regression analysis of mandibular bone mass over time was performed for each woman.

RESULTS

Twenty-two of 26 women who took calcium and vitamin D plus E/HRT for 5 years had small mandibular bone mass increases (0.35 +/- 0.38%, P<0.001). Seventeen of 19 women who took only calcium and vitamin D for 3 years had increases in mandibular bone mass (0.74 +/- 0.89%, P<0.002). The largest gains in mandibular bone mass occurred during the first 3 years of the study.

CONCLUSIONS

The data of this study indicate that E/HRT and/or calcium and vitamin D may result in increases of mandibular bone mass in postmenopausal women. Because of the long-term risks associated with E/HRT, caution should be exercised in prescribing E/HRT for prevention of chronic menopausal conditions.

Prevention of postmenopausal bone loss with exchange for short-term HRT for 1alpha-hydroxycholecalciferol

OBJECTIVE

The present study investigated bone turnover with exchange of hormone replacement therapy (HRT) by treatment with 1alpha-hydroxycholecalciferol in early postmenopausal women.

METHODS

Subjects included a total of 75 postmenopausal women between 49 and 59 years of age who visited the Department of Obstetrics and Gynecology at Osaka Medical College Hospital for regular gynecological checkups and menopausal disorder, postmenopausal osteoporosis or hyperlipidemia, and were diagnosed with menopausal disorder or osteopenia. Changes in bone turnover and vertebral bone mineral density (BMD) in 28 patients who had undergone HRT; conjugated equine estrogen 0.625 mg daily and medroxyprogesterone acetate 2.5 mg daily) for at least 2 years and then switched to 1alpha-hydroxycholecalciferol (0.5 microg orally twice daily) and in 26 patients who were observed without drug administration after discontinuation of HRT were compared with those in 37 patients who continued HRT. BMD of the lumbar spine (L2-4) was determined using Dual Energy X-ray Absorptiometry.

RESULTS

While we observed a significant decrease in vertebral bone mass in the HRT-no medication group at 12 months (P=0.049) and 18 months (P=0.013), there was no significant decrease in vertebral bone mass in either the continuous HRT group or the group with change of HRT to 1alpha-hydroxycholecalciferol. In the group with change of HRT to 1alpha-hydroxycholecalciferol, although urinary pyridinoline level increased significantly from the baseline level throughout the study period (P<0.05), serum propeptide of type-1 procollagen (P1CP) level also increased significantly from the baseline level throughout this period (P<0.001). Furthermore, significant increase from the baseline value (P<0.01) was observed in serum osteocalcin level at 6, 12 and 18 months.

CONCLUSIONS

These results indicate that switching to 1alpha-hydroxycholecalciferol therapy after short-term HRT increased both bone resorption and bone formation, and permitted maintenance of increase in bone mass due to HRT for at least 18 months, though this switching accelerated bone turnover. This may have occurred because stimulation of bone formation induced by HRT was maintained by 1alpha-hydroxycholecalciferol, though bone turnover was slightly promoted because of withdrawal of HRT. This method was thus found to be very effective in preventing bone loss in patients who have discontinued HRT and are considered relatively contraindicated for use of estrogen.

Effects of 5-year treatment with elcatonin and alfacalcidol on lumbar bone mineral density and the incidence of vertebral fractures in postmenopausal women with osteoporosis: a retrospective study

The purpose of this retrospective study was to compare the effects of long-term treatment (5 years) with elcatonin and alfacalcidol on bone mineral density (BMD) and the incidence of vertebral fractures in postmenopausal women with osteoporosis. Fifty-six osteoporotic women, more than 5 years after menopause and 58-79 years of age, were enrolled in the study and allocated to an elcatonin treatment group (20 units IM, weekly; n = 30) or an alfacalcidol treatment group (1 micro g/day, daily; n = 26). BMD of the lumbar spine (L2-L4) was measured by dual energy X-ray absorptiometry at baseline and every year for 5 years. There were no significant differences in age, body mass index, years since menopause, BMD, or number of prevalent vertebral fractures at baseline between the two groups. One-way analysis of variance with repeated measurements showed no significant longitudinal changes in BMD in either group, suggesting that both treatments sustained the BMD over 5 years. Two-way analysis of variance with repeated measurements also showed no significant differences in longitudinal changes in BMD between the two groups, suggesting that the effects of the two treatments on BMD were similar. However, the number of incident vertebral fractures per patient was significantly lower in the alfacalcidol treatment group than in the elcatonin treatment group (0.80 +/- 1.19 and 2.08 +/- 2.73, respectively; P < 0.05). These findings indicate that both treatments appeared to sustain lumbar BMD similarly over a 5-year period in postmenopausal women with osteoporosis, but alfacalcidol treatment may be superior to elcatonin treatment regarding the incidence of vertebral fractures. Further study with prospective observations are needed to confirm the results of the present study.

Effects of chronic administration of zonisamide, an antiepileptic drug, on bone mineral density and their prevention with alfacalcidol in growing rats

We investigated the effects of chronic administration of zonisamide, an antiepileptic agent, on bone metabolism in growing rats. Administration of zonisamide at a dose of 80 mg/kg per day, s.c. for 5 weeks significantly decreased bone mineral density (BMD) at the tibial metaphysis and the diaphysis. The percent rate of decrease in BMD at the tibial metaphysis and the tibial diaphysis was 9.2% and 5.0%, respectively. There was no significant difference between these groups in the growth of the rats. Treatment with zonisamide at a dose of 80 mg/kg increased serum pyridinoline level, a marker of bone resorption, while it does not affect the serum intact osteocalcin level, a marker of bone formation. Combined administration of alfacalcidol, an active vitamin D(3) metabolite, at a dose of 0.1 microg/kg per day with zonisamide prevented a decrease in BMD and showed an increase of serum pyridinoline levels. These results suggest that zonisamide may cause bone loss by accelerating bone resorption rather than inhibiting bone formation. Moreover, the bone loss induced by zonisamide could be prevented by combining zonisamide with alfacalcidol.

Role of the vitamin D-endocrine system in the pathophysiology of postmenopausal osteoporosis

Impaired calcium absorption and impaired adaptation to a low calcium diet are common features of aging in women and these processes are even more severely impaired in patients with osteoporotic fractures. The calcium absorption defects are associated with several abnormalities of the vitamin D-endocrine system including secondary hyperparathyroidism, intestinal resistance to 1,25-dihydroxyvitamin D (1,25(OH)(2)D) action, decreased 1,25(OH)(2)D production due to impaired 25(OH)D 1alpha-hydroxylase activity, and, in some elderly persons, nutritional deficiency of vitamin D. However, in postmenopausal women, most of these abnormalities are normalized by administration of physiologic replacement dosages of estrogen and, thus, appear to be secondary consequences of estrogen deficiency. Nonetheless, a minority of them, especially nutritional vitamin D deficiency and impaired 25(OH)D 1alpha-hydroxylase activity late in life, appear to be primary and are independent of estrogen deficiency.

Comparison of incadronate and alfacalcidol on increased bone turnover caused by ovariectomy in rats

Mineral density of trabecular bone at the metaphyses of right tibiae was measured by peripheral quantitative computed tomography (pQCT) in ovariectomized rats. Bone mineral density (BMD) decreased dramatically in the 4 weeks following ovariectomy, suggesting that the method is sensitive enough to detect decreased bone mineral density within a short period. Orally administered incadronate dose dependently inhibited the decrease in trabecular bone mineral density induced by ovariectomy, as assessed 4 weeks after surgery. Significant inhibition was observed at doses of more than 0.3 mg/kg/day. Moreover, incadronate at doses of 1 mg/kg or more inhibited the increase in urinary deoxypyridinoline levels induced by ovariectomy, and although slightly increased serum intact parathyroid hormone (PTH) levels were observed, no significant alteration in serum calcium ion levels or urinary calcium excretion occurred. In contrast, while alfacalcidol inhibited the decrease in bone mineral density and the increase in urinary deoxypyridinoline levels at a dose of 300 ng/kg, it significantly lowered serum intact PTH levels and elevated serum free calcium levels as well as urinary calcium excretion. These results suggest that incadronate exerts its pharmacological effect (inhibition of bone resorption and increase in bone mass) by a mechanism different from that of alfacacidol.

Effects of the combined use of calcitonin and 1 alpha-hydroxycholecalciferol on vertebral bone loss and bone turnover in women with postmenopausal osteopenia and osteoporosis: a prospective study of long-term and continuous administration with low dose calcitonin

OBJECTIVES

The present study investigates the effect of long-term and continuous treatment with low dose calcitonin in combination with 1 alpha-hydroxycholecalciferol on vertebral bone mass in early postmenopausal women.

METHODS

A total of 202 postmenopausal women between 53 and 58 years of age were recruited individually and randomly assigned to one of four groups. Comparisons were made among groups of women receiving calcitonin alone (10 IU i.m. twice a month), 1 alpha-hydroxycholecalciferol alone (0.5 microg orally twice daily), a combination of the above two agents, or no treatment. Bone mineral density (BMD) of lumber spine (L2-4) was determined using Dual Energy X-ray Absorptiometry. The study was carried out prospectively over a 2-year period.

RESULTS

We observed a significant increase in vertebral bone mass in the combined treatment regimen of calcitonin and 1 alpha-hydroxycholecalciferol (3.44% at 12 months in the combination group vs 1.40,0.92, and -0.70% in the calcitonin alone, 1 alpha-hydroxycholecalciferol alone, and control groups, respectively; 4.51% at 24 months in the combination group vs 2.21,1.04, and -3.61% in the calcitonin alone, 1 alpha-hydroxycholecalciferol alone, and control groups, respectively). Serum PTH, osteocalcin levels and alkaline phosphatase activity decreased significantly within 12 months whereas urinary pyridinoline/creatinine ratio decreased at 24 months in the combination group. We observed mild adverse effects in 25.0% (7/28) and 30.0% (6/20) of combination regimen and calcitonin treatment cases, respectively.

CONCLUSIONS

The results of the study suggest that the combination treatment regimen increased vertebral bone loss in early postmenopausal women to a greater extent than did calcitonin alone or 1 alpha-hydroxycholecalciferol alone.

Effect of exercise training and detraining on bone mineral density in postmenopausal women with osteoporosis

We examined the effect of exercise training and detraining on bone mineral density (BMD) in postmenopausal women with osteoporosis. Thirty-five postmenopausal women with osteoporosis, aged 53-77 years, were randomly assigned to three groups: a control group (n = 20), a 2-year exercise training group (n = 8), and an 1-year exercise training plus 1-year detraining group (n = 7). Exercise training consisted of daily brisk walking and gymnastic training. Calcium lactate, 2.0 g, and 1alpha-hydroxyvitamin D3, 1 microg were supplied daily to all subjects. No significant differences in initial lumbar BMD, measured by dual-energy X-ray absorptiometry (DXA) were found among the three groups. The mean percent change in BMD compared with the baseline was significantly higher at 1 and 2 years in the exercise training group and at 1 year in the detraining group than in the control group, and did not differ significantly at 2 years between the detraining and control groups. These findings indicate that our exercise training program led to a significant increase in lumbar BMD in postmenopausal women with osteoporosis compared with the control, but that the BMD reverted toward a level that was not significantly different from the control with detraining. Continued exercise training is needed to maintain the bone mass gained through exercise training.

Urinary free deoxypyridinoline by chemiluminescence immunoassay: analytical and clinical evaluation

We evaluated an automated chemiluminescence immunoassay (CLIA) developed for the measurement of urinary free deoxypyridinoline (DPD). The new DPD method by CLIA is based on the competition of DPD with particle-bound pyridinoline for a limited amount of monoclonal mouse anti-DPD antibody. Total imprecision (CV) was 3.2–9.0% at 30–270 nmol/L. Regression analysis of urinary DPD concentration (second morning-void) measured by CLIA (y) and enzyme immunoassay (EIA) for adult volunteers (n = 449) with and without bone disease revealed a best fit equation of: y = 1.08 ± 0.03x − 1.15 ± 0.98 nmol/L (r = 0.964, Sy‖x = 14 nmol/L). CLIA and EIA methods were correlated with HPLC measurement of urinary free DPD (r = 0.846 and 0.871, respectively). For healthy adults, the creatinine-normalized excretion of DPD (mean ± SD) measured by CLIA for 61 men (4.1 ± 1.2 μmol DPD/mol creatinine) and 76 premenopausal women (5.3 ± 1.8 μmol DPD/mol creatinine) did not differ significantly (P &gt;0.05) from DPD excretion measured by EIA, and both immunoassays showed a significant gender difference (P &lt;0.001) in reference intervals. In a clinical trial, DPD excretion (μmol DPD/mol creatinine) measured by CLIA differed substantially from the reference population for 54 untreated pagetic (12.7 ± 8.0 SD), 255 untreated osteoporotic (7.5 ± 4.1), 21 osteomalacic (12.4 ± 8.5), 17 primary hyperparathyroid (9.4 ± 4.4), and 14 secondary hyperparathyroid (9.2 ± 5.1) patients. Clinical sensitivities of the CLIA and EIA methods range from 38% to 80% in bone disorders and limit the use of the DPD measurement in disease detection. DPD excretion after pamidronate treatment in a subgroup of the pagetic patients fell dramatically as assessed by CLIA or EIA. We conclude that the automated CLIA method for DPD is a convenient and reliable method that may aid in the evaluation and management of bone disease and is applicable to high volume testing in the routine clinical laboratory.