Coronary calcium score in patients with post-surgical hypoparathyroidism

Objective

This study aimed to evaluate the cardiovascular risk of patients with post-surgical hypoparathyroidism through coronary calcium score (CACS) evaluation andcardiovascular risk calculators.

Subjects and methods

Patients with post-surgical hypoparathyroidism (HG = 29) were compared to a control group (CG = 29), matched by sex and age. Demographic and clinical data were captured by a questionnaire or patient files. Both groups performed a thoracic-computed tomography to evaluate the CACS and the cardiovascular risk was calculated by two risk calculators.

Results

In the HG, the supplementation of calcium varied between 500 to 2,000 mg/day and the mean calcitriol was 0.5 ± 0.29 mcg/day. The mean serum calcium and phosphorus were 8.32 ± 0.68 and 4.92 ± 0.87 mg/dL, respectively, and in the range recommended for hypoparathyroidism. The Brazilian Society of Cardiology's risk calculator showed a difference among groups, with no patient in the HG with low risk, but the CACS was similar. A positive CACS in the HG was associated with obesity and high BMI but not with calcium and/or vitamin D supplementation.

Conclusion

In conclusion, patients with hypoparathyroidism did not show increased CACS, and it was not related to supplementation.

Calcium supplementation for the prevention of pre-eclampsia: Challenging the evidence from meta-analyses

OBJECTIVE

To investigate the validity of the conclusion from Cochrane reviews and meta-analyses that treatment with calcium supplementation during pregnancy reduces the risk for pre-eclampsia by 55%, which has been influential in international guidelines and future research.

DESIGN

Sensitivity analysis of data from Cochrane reviews of trials evaluating high-dose calcium supplementation (of at least 1 g/day) for reduction of pre-eclampsia risk.

SETTING

Systematic review and meta-analysis.

POPULATION

The Cochrane reviews and meta-analyses included 13 trials enrolling a total of 15 730 women. Random-effects meta-analysis of these studies resulted in a mean risk ratio (RR, calcium/placebo) of 0.45 (95% confidence interval [CI] 0.31-0.65; p < 0.0001).

METHODS

We carried out a sensitivity analysis of evidence from the relevant Cochrane review, to examine the impact of study size.

MAIN OUTCOME MEASURES

pre-eclampsia.

RESULTS

In the three largest studies, accounting for 13 815 (88%) of total recruitment, mean RR was 0.92 (95% CI 0.80-1.06) and there was no evidence of heterogeneity between studies (I2  = 0). With inclusion of the smaller studies, mean RR decreased to 0.45 and I2 increased to 70%.

CONCLUSIONS

In assessment of the effect of calcium supplementation on pre-eclampsia risk, the naive focus on the mean of the random-effects meta-analysis in the presence of substantial heterogeneity is highly misleading.

Dilated cardiomyopathy in patients with hypoparathyroidism: A narrative review

Background

Hypoparathyroidism is a rare endocrine disorder characterized by low blood calcium levels, elevated phosphorus levels, and insufficient parathyroid hormone production. It can lead to dilated cardiomyopathy (DCM), a cardiac condition characterized by enlarged ventricles and reduced heart function. This review aims to explore the relationship between hypoparathyroidism and DCM, the impact of calcium on cardiac function, and the potential for DCM reversal with calcium supplementation.

Methods

A comprehensive literature search was conducted using PubMed, Google Scholar, and relevant keywords and Mesh terms. Case reports evaluating dilated cardiomyopathy in patients with Hypoparathyroidism were included in the study. Additionally, references cited in each study were carefully examined to identify relevant reports. The cases included in the review were analyzed, and common cardiac manifestations, diagnostic approaches, and management were identified.

Results

DCM in hypoparathyroidism presents with symptoms of heart failure, reduced ejection fraction, and impaired left ventricular function. Laboratory tests show low serum calcium levels and elevated phosphate levels. Prompt diagnosis and treatment with calcium and vitamin D supplementation can lead to improvements in cardiac function.

Conclusion

Hypoparathyroidism-induced DCM is reversible with timely calcium and vitamin D supplementation. Patient compliance with prescribed medications and supplements is crucial to prevent and manage cardiac complications. Regular follow-up check-ups and monitoring of calcium levels can aid in early detection and improve patient outcomes. Educating patients about the importance of treatment adherence can significantly reduce the risk of developing DCM and other cardiac symptoms associated with hypoparathyroidism. Routine follow-up of DCM among patients with endocrine disorders is recommended.

A randomized field trial assessing the timing of postpartum calcium bolus administration on milk yield of multiparous Holstein cows

Recent studies have shown that cows with subclinical hypocalcemia (SCH) at 4 d in milk (DIM), regardless of their blood Ca concentration before that time point, suffer from an increased early-lactation disease risk and reduced milk yield, whereas cows experiencing a transient reduction in blood Ca that regain normocalcemia by 4 DIM are at a reduced risk of disease and have greater milk yields. With a goal of improving outcomes for dyscalcemic cows with SCH at 4 DIM, our primary objective was to assess the effect of a herd-level oral Ca bolus strategy that delayed supplementation to 24 and 48 h postpartum on productive performance of multiparous Holstein cows. Our secondary objectives were to assess the effects of delayed Ca bolus supplementation on blood Ca concentration, disease incidence within 30 DIM, and pregnancy risk to first service. At calving, multiparous cows on a single commercial dairy farm in Iran were randomly assigned to 1 of 3 treatment groups: (1) control, no Ca bolus administration (CON; n = 95); (2) traditional bolus, one Ca bolus administered immediately following calving and a second Ca bolus administered 24 h after calving (TRD, n = 102); or (3) experimental bolus, one Ca bolus administered 24 h after calving with a second Ca bolus administered 48 h after calving (EXP, n = 99). Blood samples were collected at 0, 24, 48, 72, and 96 h, and 7 d after parturition, with sampling occurring before bolus administration for the TRD (0 and 24 h) and EXP (24 and 48 h) groups. A general linear mixed model was created to analyze the change milk yield over the first 4 monthly tests and serum Ca concentrations over 7 DIM. Given the lack of disease events diagnosed within 30 DIM, no statistical analysis was conducted for this outcome. The effect of treatment group on risk of pregnancy to first service was assessed using Poisson regression. The incidence of dyscalcemia within CON cows was 72%. We found no difference in mean monthly milk yield among treatment groups across the first 4 tests, with an average monthly production of 51.8 ± 8.8 kg/d for CON cows, 52.5 ± 8.7 kg/d for TRD cows, and 51.8 ± 8.7 kg/d for EXP cows. Mean blood Ca concentration also did not differ across 7 DIM among treatment groups and was 2.04 mmol/L [95% confidence interval (CI) = 2.00 to 2.07 mmol/L] for CON cows, 2.06 mmol/L (95% CI = 2.03 to 2.09 mmol/L) for TRD cows, and 2.09 mmol/L (95% CI = 2.05 to 2.12 mmol/L) for EXP cows. The risk of pregnancy to first service was numerically greater for CON than TRD and EXP cows but not statistically different; however, our study was underpowered for this outcome. Under the conditions of our study, our findings suggest that delaying oral Ca bolus supplementation to 24 and 48 h postpartum has no effect on milk production across the first 4 monthly tests.

All-cause and cause-specific mortality risks associated with calcium supplementation with or without Vitamin D: A nationwide population-based study

BACKGROUND

Current evidence regarding the mortality outcomes associated with calcium supplementation with or without low dose vitamin D is conflicting.

OBJECTIVES

To investigate the effects of calcium supplementation with or without vitamin D on all-cause and cause-specific mortalities in a large-scale cohort.

METHODS

This study used data from the Korean National Health Insurance System database and National Death Registry. A total of 27,846 participants aged >55 years who had taken calcium supplements with or without vitamin D for at least 90 days (calcium supplementation only [CaO], n = 6,256; calcium supplementation in combination with vitamin D [CaD], n = 21,590) were matched in a 1:1 ratio to those who did not take calcium or vitamin D supplements (control group) using propensity scores.

RESULTS

No difference in all-cause mortality risk was found between the CaO and control groups. [adjusted hazard ratio (HR) = 1.00; 95% confidence interval (CI): 0.92-1.10]. However, all-cause mortality was lower in the CaD group [HR = 0.85; 95% CI: 0.80-0.89] compared with that in the control group. Mortality risk associated with cardiovascular disease (CVD) was decreased in the CaD group when the daily vitamin D dose received was less than 1,000 IU [HR = 0.72; 95% CI: 0.64-0.81]. Subgroup analysis showed significant effect of vitamin D with calcium in individuals who were female, aged ≥65 years, or had previous history of cancer or CVD.

CONCLUSION

In combination with calcium, vitamin D supplementation provides better outcomes for all-cause mortality, particularly cardiovascular-associated mortality, in a duration-dependent manner. This article is protected by copyright. All rights reserved.

The effect of calcium supplementation in people under 35 years old: A systematic review and meta-analysis of randomized controlled trials

Background:

The effect of calcium supplementation on bone mineral accretion in people under 35 years old is inconclusive. To comprehensively summarize the evidence for the effect of calcium supplementation on bone mineral accretion in young populations (≤35 years).

Methods:

This is a systematic review and meta-analysis. The Pubmed, Embase, ProQuest, CENTRAL, WHO Global Index Medicus, Clinical Trials.gov, WHO ICTRP, China National Knowledge Infrastructure (CNKI), and Wanfang Data databases were systematically searched from database inception to April 25, 2021. Randomized clinical trials assessing the effects of calcium supplementation on bone mineral density (BMD) or bone mineral content (BMC) in people under 35 years old.

Results:

This systematic review and meta-analysis identified 43 studies involving 7,382 subjects. Moderate certainty of evidence showed that calcium supplementation was associated with the accretion of BMD and BMC, especially on femoral neck (standardized mean difference [SMD] 0.627, 95% confidence interval [CI] 0.338–0.915; SMD 0.364, 95% CI 0.134–0.595; respectively) and total body (SMD 0.330, 95% CI 0.163–0.496; SMD 0.149, 95% CI 0.006–0.291), also with a slight improvement effect on lumbar spine BMC (SMD 0.163, 95% CI 0.008–0.317), no effects on total hip BMD and BMC and lumbar spine BMD were observed. Very interestingly, subgroup analyses suggested that the improvement of bone at femoral neck was more pronounced in the peripeak bone mass (PBM) population (20–35 years) than the pre-PBM population (<20 years).

Conclusions:

Our findings provided novel insights and evidence in calcium supplementation, which showed that calcium supplementation significantly improves bone mass, implying that preventive calcium supplementation before or around achieving PBM may be a shift in the window of intervention for osteoporosis.

Funding:

This work was supported by Wenzhou Medical University grant [89219029].

Osteoporosis and bone fractures are common problems among older people, particularly older women. These conditions cause disability and reduce quality of life. Progressive loss of bone mineral density is usually the culprit. So far, strategies to prevent bone weakening with age have produced disappointing results. For example, taking calcium supplements in later life only slightly reduces the risk of osteoporosis or fracture. New approaches are needed.

Bone mass increases gradually early in life and peaks and plateaus around 20-35 years of age. After that period, bone mass slowly declines. Some scientists suspect that increasing calcium intake during this period of peak bone mass may reduce osteoporosis or fracture risk later in life.

A meta-analysis by Liu, Le et al. shows that boosting calcium intake in young adulthood strengthens bones. The researchers analyzed data from 43 randomized controlled trials that enrolled 7,382 participants. About half the studies looked at the effects of taking calcium supplements and the other half analyzed the effects of a high calcium diet. Boosting calcium intake in people younger than age 35 improved bone mineral density throughout the body. It also increased bone mineral density at the femoral neck, where most hip fractures occur. Calcium supplementation produced larger effects in individuals between the ages of 20 and 35 than in people younger than 20.

Both high calcium diets and calcium supplements with doses less than 1000 mg/d boosted bone strength. Higher dose calcium supplements did not provide any extra benefits. The analysis suggests people should pay more attention to bone health during early adulthood. Large randomized clinical trials are needed to confirm the long-term benefits of boosting calcium intake during early adulthood. But if the results are validated, taking calcium supplements, or eating more calcium-rich foods between the ages of 20 and 35 may help individuals build healthier bones and prevent fractures and osteoporosis later in life.

Metformin-induced vitamin B12 deficiency can cause or worsen distal symmetrical, autonomic and cardiac neuropathy in the patient with diabetes

Metformin blocks the absorption of vitamin B12 through a mechanism that has not been established but could be because of interference with the calcium-dependent binding of the intrinsic factor vitamin B12 complex to the cubam receptor in the terminal ileum. The subsequent deficiency of vitamin B12 may cause or accelerate distal symmetrical and autonomic neuropathy in the patient with diabetes. Several observational studies and meta-analyses have reported a significant association between metformin utilization and vitamin B12 deficiency. Prospective studies have shown that not only do metformin utilizers have lower vitamin B12 levels but they also have higher frequencies of distal symmetrical polyneuropathy and autonomic neuropathy (including cardiac denervation, which is associated with increased incidences of cardiac arrhythmias, cardiac events and mortality). Therefore, periodic monitoring of vitamin B12 is recommended in all patients who utilize metformin, particularly if metformin has been used for over 5 years at which stage hepatic stores of vitamin B12 would probably be depleted. Factors that accelerate the loss of hepatic vitamin B12 stores are proton pump inhibitors, bariatric surgery, being elderly and having an increased turnover of red blood cells. If serum vitamin B12 levels are borderline, measurement of methylmalonic acid and homocysteine levels can detect vitamin B12 deficiency at its earliest stage. Therapies include prophylactic calcium and vitamin B12 supplements, metformin withdrawal, replenishing vitamin B12 stores with intramuscular or oral vitamin B12 therapy and regular monitoring of vitamin B12 levels and vitamin B12 supplements if metformin continues to be utilized. With adequate vitamin B12 replacement, while symptoms of neuropathy may or may not improve, objective findings of neuropathy stabilize but do not improve.

Trauma-induced hypocalcemia

BACKGROUND

Trauma-induced hypocalcemia is an underappreciated complication of severe injury but is well known to result in the derangement of an array of physiological regulatory mechanisms. Existing literature provides a compelling link between hypocalcemia and worse trauma-induced coagulopathy and increased mortality after injury.

STUDY DESIGN AND METHODS

This narrative review evaluates available data related to the risk factors, mechanisms, and treatment of hypocalcemia after severe injury. The authors did not perform a systemic review or meta-analysis.

RESULTS AND DISCUSSION

The interplay of acidosis, hypothermia, and coagulopathy with hypocalcemia potentiates the bloody vicious cycle of hemorrhagic shock which has been the paradigm of trauma resuscitation for over half a century. However, current screening and treatment of postinjury hypocalcemia are relegated to a secondary consideration in trauma resuscitation. We conclude calcium supplementation should be a primary tier intervention for life-threatening injury.

Calcium Supplementation, Risk of Cardiovascular Diseases, and Mortality: A Real-World Study of the Korean National Health Insurance Service Data

Few studies have investigated the effects of calcium supplementation on cardiovascular outcomes in individuals with low calcium intake in real-world settings. This study examined the association between calcium supplementation and cardiovascular outcomes in the Korean population in a real-world setting. This large retrospective cohort study included patients aged ≥45 years first prescribed calcium supplements in 2010. Age- and sex-matched controls were recruited among those who had no prescription for calcium supplements. Longitudinal data were collected on 31 December 2018. Kaplan−Meier estimation and Cox proportional hazard regression analysis were performed. The cumulative incidence of acute myocardial infarction, ischemic stroke, and death was significantly higher in the calcium supplementation group than in the control group (p < 0.05 by log-rank test). The calcium supplementation group had a significantly higher risk of myocardial infarction, ischemic stroke, and death than the control group. Compared to the control group, the hazard ratios (95% confidence intervals) of the incidence of myocardial infarction, stroke, and death in the supplementation group were 1.14 (1.03−1.27), 1.12 (1.05−1.20), and 1.40 (1.32−1.50), respectively, after adjusting for confounding variables. Considering the associated cardiovascular risk, calcium supplementation for osteoporosis treatment should be administered cautiously.

Risk Analysis of Denosumab-Induced Hypocalcemia in Bone Metastasis Treatment: Renal Dysfunction Is Not a Risk Factor for Its Incidence in a Strict Denosumab Administration Management System with Calcium/Vitamin D Supplementation

We have reported that a strict denosumab administration management system with oral calcium/vitamin D supplementation attenuates denosumab-induced hypocalcemia in 158 cancer patients with bone metastasis. In this report, 27.8% of the patients experienced hypocalcemia, including 0.6% with grade 2. So far, the risk factors for ≥grade 2 hypocalcemia incidence have been identified in denosumab-treated cancer patients, including patients without calcium/vitamin D supplementation. Therefore, the present study aimed to reveal the factors that affect all-grade hypocalcemia incidence with calcium/vitamin D supplementation and team medical care according to the management system. A receiver operating characteristic curve analysis suggested that the cutoff of baseline serum calcium level for all-grade hypocalcemia incidence was 9.3 mg/dL. Multivariate analysis revealed that age ≥65 years (odds ratio, 95% confidence interval: 2.57, 1.11-5.95, p = 0.03), grade 1 or higher serum alkaline phosphatase elevation (3.70, 1.71-8.00, p < 0.01), an adjusted serum calcium level of less than 9.3 mg/dL (3.21. 1.25-8.24, p = 0.02) at baseline, and co-administration of cytotoxic agents (2.33, 1.06-7.11, p = 0.03) are risk factors for the incidence of all-grade hypocalcemia. However, renal dysfunction, which has been suggested to be a risk factor in previous reports, was not a factor. In conclusion, we revealed the risk factors for all-grade hypocalcemia in calcium/vitamin D supplementation and awareness, as demonstrated by the management system. Moreover, renal dysfunction was not a risk factor in our strict denosumab administration management system. Our results support the value of early detection of hypocalcemia incidence to guide the selection of an appropriate management strategy.

Calcium supplementation during pregnancy and maternal and offspring bone health: a systematic review and meta-analysis

Insufficient calcium intake during pregnancy may lead to maternal bone resorption and lower bone density of offspring. We evaluated the impact of supplementary calcium with or without vitamin D during pregnancy on maternal and offspring bone mineral density (BMD) and teeth firmness of the offspring. Randomized controlled trials (RCTs) were searched systematically in 11 databases. Two researchers independently screened the titles and abstracts of 3555 records and the full texts of 31 records to examine eligibility. The search yielded seven RCTs (11 reports, n = 1566).  No advantage of calcium supplementation was found on maternal BMD after delivery or during breastfeeding, or on offspring BMD, even when dietary calcium intake was low. The results were neither modified by the dose of calcium nor concomitant vitamin D administration. A suspicion of some long‐term harm of the intervention on maternal BMD and growth of female offspring was raised based on the data. One study suggested some benefit of high‐dose calcium supplementation on offspring teeth firmness at 12 years old. A low number of the studies and abundant missing data reduced the quality of the findings. The impact of calcium supplementation on maternal and offspring bone health was deemed unknown because of inconclusive research results.

Acute CTX-1 Suppression With Milk Calcium or Calcium Carbonate is Independent of Visceral Fat in A Randomized Crossover Study in Lean and Overweight Postmenopausal Women

BACKGROUND

Postmenopausal women with higher visceral adipose tissue (VAT) present with suppressed bone resorption (lower c-terminal cross-linking telopeptide of type I collagen, CTX-1) and turnover (lower osteocalcin) but whether this blunts the effect of calcium is unknown.

OBJECTIVE

The primary outcome of this study was the effect of VAT on changes in CTX-1 after intake of two forms of calcium. Secondary outcomes included changes in parathyroid hormone (PTH), serum calcium, phosphorus, and alkaline phosphatase (ALP).

DESIGN

Randomized open three period crossover trial conducted between 2017-2019 at the University of South Australia among 77 lean and overweight postmenopausal women (53-79 y) with body mass index (BMI) less than 25 kg/m2 and greater than 27 kg/m2, respectively. Participants received a single dose of milk (1000 mg calcium), calcium carbonate tablet (1000 mg calcium), and fruit juice (no calcium) in random order with a seven-day washout period. Blood samples were collected at baseline and hourly for 5h. Data was analysed by repeated measures analysis of variance (ANOVA) of log-transformed data.

RESULTS

At baseline, women with higher VAT had significantly lower CTX-1 and higher PTH (44% lower and 30% higher, respectively between Q4 and Q1, P < 0.0001). VAT had no influence on the acute changes in CTX-1 or PTH with calcium or juice. A suppression of 44% in CTX-1 was seen with calcium carbonate and milk and a suppression of 18% with juice. PTH was suppressed more with calcium carbonate (47%) compared to milk (22%). Milk calcium reduced PTH and CTX-1 at 2-hour while calcium carbonate reduced PTH in 1 hour. The suppression in CTX-1 was slower with lowest levels at 4-5 hour.

CONCLUSIONS

1000 mg calcium obtained from milk or from calcium carbonate is effective in acutely suppressing bone resorption in postmenopausal women irrespective of visceral fat.This trial is registered with the Australian New Zealand Clinical Trials Registry http://www.ANZCTR.org.au/ACTRN12617000779370.aspx (ACTRN 12617000779370).

[Pharmaceutical Intervention According to Strict Management System Can Normalize Decreased Serum Calcium Level by Denosumab and Prevent Its Aggravation]

Denosumab is a fully monoclonal antibody against the receptor activator of nuclear factor kappa-B ligand (RANKL), and prevents skeletal-related events by bone metastasis. Hypocalcemia is the most typical adverse effect of denosumab use. We have developed a management system for the more efficient and safer management of denosumab administration, and evaluated pharmaceutical interventions for the better control of hypocalcemia. All pharmaceutical interventions in the system from April 2016 to March 2020 were retrospectively evaluated. We have also assessed the incidence of hypocalcemia in 158 patients who were administered denosumab for six months or more in the period. A total of 282 pharmaceutical interventions (7.0% of the total administration) were conducted. The most conducted intervention was regarding hypocalcemia, which involved the suspension of the injection and/or the increase of calcium and vitamin D supplement with 65% adoption and 17% temporary treatment suspensions. Other interventions were about hypercalcemia, request of laboratory examination and ordering supplements, dental consultation, and poor renal function. A total of 199 interventions (70.6%) were adopted, with 33 administrations suspended. The frequency of hypocalcemia was 27.8% with just one patient having grade 2 hypocalcemia, suggesting that there were no severe cases. Moreover, hypocalcemia was significantly normalized following pharmaceutical intervention and/or handling by physicians (p=0.02) according to the system. Conversely, the normalization rate in hypercalcemia did not differ according to the countermeasures. In conclusion, pharmaceutical interventions according to our management system benefit safe denosumab treatment, especially in severe hypocalcemia prevention.

[G protein-coupled estrogen receptor increases vascular endothelial inflammatory response after ovariectomized mice]

OBJECTIVE

To investigate the effects of calcium supplementation on the inflammatory response of vascular endothelial cells and the possible role and mechanism of G protein-coupled estrogen receptor(GPER)under the physiological conditions of estrogen deficiency(ovary removal).

METHODS

Forty healthy 8-week-old female C57 BL/6 mice were divided into 4 groups by random number table according to body weight, which were respectively the control group, ovarian removal group, ovarian removal high calcium group, and G1 ovarian removal high calcium group, each group ten. One week after the basal diet, the control group underwent sham surgery, and the ovaries-removed group, ovarian-removed high-calcium group, and G1 ovarian-removed high-calcium group were treated for ovarian removal. The control group and the ovary-removed group were fed basic feed(AIN-93 G, calcium content 0. 5%), the ovarian-removed high-calcium group and the G1 implanted ovarian-removed high-calcium group were fed high-calcium feed(adjusted AIN-93 G, calcium content 1. 5%). Three months later, mice in the control, ovarian-removed, and ovarian-reduced high-calcium groups were implanted with a placebo subcutaneously, and G1 ovarian-removed high-calcium groups were implanted with a GPER specific agonist G1, intervention for 28 days, under the anesthesia state, collect blood from 40 mice, isolate serum to measure vascular endothelial adhesion factor-1(VCAM-1), tumor necrosis factor-α(TNF-α), estradiol and blood calcium concentration; take aortic arch for immunization histochemical detection of transient receptor potential channel 1(TRPC1), phosphorylated-extracellular regulated kinase(p-ERK)1/2, VCAM-1 and CD68 expression levels. SPSS software performs statistical analysis and draws conclusion.

RESULTS

The differences in weight gain between the three groups and the control group were statistically significant(P&lt;0. 05), while the differences in weight between the three groups were not statistically significant(P&gt;0. 05). There were statistically significant differences in serum estradiol levels between the three groups, the ovariectomized high calcium group, and the G1 ovariectomized group implanted with the control group(P&lt;0. 05). The difference was not statistically significant(P&gt;0. 05). The differences in serum VCAM-1 concentrations between the control group and the other three groups were statistically significant(P&lt;0. 05). The difference in serum VCAM-1 concentration was statistically significant between the ovariectomized group and the implanted G1 ovariectomized high calcium group and the ovariectomized high calcium group(P&lt;0. 05). There was no significant difference in serum VCAM-1 concentration in the group(P&gt;0. 05). There was no significant difference in TNF-α concentration between the four groups(P&gt;0. 05). By immunohistochemistry, the percentages of TRPC1, p-ERK1/2, VCAM-1, and CD68-positive cell areas in the ovarian high-calcium group were significantly higher than those in the ovarian-removed group and the G1-ovarian-removed high-calcium group. The difference was statistically significant(P&lt;0. 05), and the difference in the percentage of positive cell area between the ovarian-removed group and the G1-removed high-calcium group was not statistically significant(P&gt;0. 05).

CONCLUSION

In the state of estrogen deficiency, calcium supplementation causes an increase in inflammatory response, which may be related to the change in GPER activity, and then affect the TRPC1/ERK1/2 pathway.

The joint effect of energy reduction with calcium supplementation on the risk factors of type 2 diabetes in the overweight population: a two-year randomized controlled trial

Both excessive energy intake and low calcium intake are inversely associated with the aging-related diseases, particularly for type 2 diabetes mellitus(T2DM). This study examined whether energy reduction coupled with calcium supplementation aided in the prevention of T2DM among the overweight population. A randomized controlled trial(RCT) of 1021 overweight participants was performed, in which participants were randomly assigned to 4 groups: 1) energy-reduction group(ERG), 2) calcium supplementation group(CSG), 3) energy-reduction with calcium supplementation group(ER-CSG), 4) control group(CG). Nutritional habits, anthropometric and diabetes-related indicators were measured at baseline and each follow-up time. To analyze the separate effects of dietary energy reduction and calcium supplementation, ERG and ER-CSG were integrated into ERGs. Similarly, CSG and ER-CSG were integrated into CSGs. Compared to the non-energy-reduction groups(NERGs), ERGs had lower values of ΔBMI(-0.9kg/m²), ΔFSG (-0.34mmol/L), ΔHbA1c(0.16%), and ΔHOMA-IR(-0.13), and higher value of ΔGutt index(-5.82). Compared to the non-calcium supplementation groups(NCSGs), the ΔGutt index(-5.46) in CSGs showed a significant decrease. Moreover, these risk factors for T2DM were most effectively ameliorated in ER-CSG group with the decreased values of ΔFSG(-0.42mmol/L), ΔGutt index(-0.73), and the slowest increasing rate value of Δ2h-glucose(0.37mmol/L). This RCT demonstrated that energy-reduction with calcium supplementation was a useful dietary intervention strategy for preventing the development of T2DM in the overweight population.

Calcium intake from different food sources in Italian women without and with non-previously diagnosed osteoporosis

An adequate calcium and vitamin D intake may play a role in preventing osteoporosis, but the contribution of the different food sources of calcium with regards to the risk of osteoporosis been barely explored. This observational study evaluated the calcium intake through a food frequency questionnaire in 126 adult women with not previously diagnosed osteoporosis undergoing Dual-energy X-ray Absorptiometry (DXA) to screen for osteoporosis, and to correlate the calcium intake with parameters of bone density, measured by DXA. Total daily calcium intake and daily intake from food were similar among women found to have osteoporosis, osteopenia or normal condition. The main food source was milk and dairy products, while calcium supplementation was consumed by only 14% of subjects, irrespectively from osteoporosis conditions. DXA parameters were not significantly correlated with total daily calcium intake and calcium from food. The present study highlighted no qualitative and quantitative differences in the consumption of food groups contributing to calcium intakes in women with and without osteoporosis.

Calcium supplementation for improving bone density in lactating women: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Clinical trials evaluating the effect of calcium supplementation on bone loss in lactating women have been small, with inconsistent results.

OBJECTIVES

We aimed to determine the effect of calcium supplementation on bone mineral density (BMD) in lactating women.

METHODS

An electronic search of databases was conducted from inception to January 2020. Two authors screened studies, extracted data, and assessed the risk of bias of eligible studies. Percentage change in BMD was pooled using random-effects models and reported as weighted mean differences (WMDs) with 95% CIs. Risk of bias was assessed using the Cochrane risk of bias tool.

RESULTS

Five randomized controlled trials including 567 lactating women were included. All had a high risk of bias. Mean baseline calcium intake ranged from 562 to 1333 mg/d. Compared with control groups (placebo/no intervention), calcium supplementation (600/1000 mg/d) had no significant effect on BMD at the lumbar spine (WMD: 0.74%; 95% CI: -0.10%, 1.59%; I2 = 47%; 95% CI: 0%, 81%; n = 527 from 5 trials) or the forearm (WMD: 0.53%; 95% CI: -0.35%, 1.42%; I2 = 55%; 95% CI: 0%, 85%; n = 415 from 4 trials). BMD at other sites was assessed in single trials: calcium supplementation had a small to moderate effect on total-hip BMD (WMD: 3.3%; 95% CI: 1.5%, 5.1%) but no effect on total body or femoral neck BMD.

CONCLUSIONS

Overall, the meta-analysis indicates that calcium supplementation does not provide clinically important benefits for BMD in lactating women. However, there was adequate dietary intake before supplementation in some studies, and others did not measure baseline calcium intake. Advising lactating women to meet the current recommended calcium intakes (with supplementation if dietary intake is low) is warranted unless new high-certainty evidence to the contrary from robust clinical trials becomes available. More research needs to be done in larger samples of women from diverse ethnic and racial groups.This systematic review was registered at www.crd.york.ac.uk/prospero as CRD42015022092.

A Pilot Study To Evaluate The Effect Of A Novel Calcium And Vitamin D-Containing Oral Bolus On Serum Calcium Levels In Holstein Dairy Cows Following Parturition

Background

The initiation of lactation challenges the ability of the modern lactating cow to maintain calcium homeostasis, and typically results in a drop in blood calcium levels, leading to mobilization of calcium reserves from skeletal stores. As such, the recommendation to provide supplemental calcium at parturition to older cows has become an industry-standard practice.

Methods

Mature cows were treated at calving and 12 hrs later with either the novel calcium bolus (NB) or a commercially available calcium bolus (CB). Blood was collected from animals at 0, 1, 6, 12, 13, and 24 hrs following calving, and the resulting serum samples were analyzed.

Results

Overall, there was no statistical difference between the NB and CB groups for blood calcium levels within the first 24 hrs following parturition (P = 0.50). Cows in both groups experienced a significant increase in serum calcium by 1 hr after parturition; however, this increase was not sustained through subsequent sampling times.

Conclusion

This pilot study demonstrates that both boluses have a similar effect in the elevation of blood calcium.

Effectiveness of programme approaches to improve the coverage of maternal nutrition interventions in South Asia

The nutritional status of women before pregnancy, during pregnancy, and after delivery has far reaching consequences for maternal health and child survival, growth, and development. In South Asia, the high prevalence of short stature, thinness, and anaemia among women of reproductive age underlie the high prevalence of child undernutrition in the region, whereas overweight and obesity are rising concerns. A systematic review of evidence (2000-2017) was conducted to identify barriers and programme approaches to improving the coverage of maternal nutrition interventions in the region. The search strategy used 13 electronic bibliographic databases and 14 websites of development and technical agencies and identified 2,247 citations. Nine studies conducted in Bangladesh (n = 2), India (n = 5), Nepal (n = 1), and Pakistan (n = 1) were selected for the review, and outcomes included the receipt and consumption of iron and folic acid and calcium supplements and the receipt of information on dietary intake during pregnancy. The studies indicate that a range of barriers acting at the individual (maternal), household, and health service delivery levels affects intervention coverage during pregnancy. Programme approaches that were effective in improving intervention coverage addressed barriers at multiple levels and had several common features: use of formative research and client assessments to inform the design of programme approaches and actions; community-based delivery platforms to increase access to services; engagement of family members, as well as pregnant women, in influencing behavioural change; actions to improve the capacity, supervision, monitoring, and motivation of front-line service providers to provide information and counselling; and access to free supplements.

An update on the problem of osteoporosis in people with epilepsy taking antiepileptic drugs

INTRODUCTION

Antiepileptic drugs (AEDs) have been associated with a negative impact on bone health. Comorbid disorders in patients with epilepsy may require drugs exerting a pro-osteoporotic effect, so a possibility of untoward interactions with AEDs is probable.

AREAS COVERED

This review discusses evidence related to the deteriorating influence of AEDs on bone, demonstrating generally stronger negative effects of conventional AEDs. Lamotrigine seems to be a safer AED in this regard. Further, literature data indicate that generally AEDs can lower the serum concentration of vitamin D. Importantly, pediatric patients are of greater risk of bone problems during therapy with AEDs, which is probably due to their effects on bone-forming processes.

EXPERT OPINION

Supplementation with vitamin D and calcium is frequently recommended in patients taking AEDs chronically. Whether to add a bisphosphonate remains an open question due to the limited data on this issue. A possibility of negative interactions exists between AEDs and other pro-osteoporotic drugs: glucocorticoids, proton pump inhibitors and aromatase inhibitors. Depression is a frequent comorbidity in patients with epilepsy. Clinical data indicate that antidepressant drugs may also increase the risk of fractures. Again, patients with epilepsy and depression may be exposed to a greater risk of osteoporosis.

Ethiopian women's perspectives on antenatal care and iron-folic acid supplementation: Insights for translating global antenatal calcium guidelines into practice

After decades of global response to iron-deficiency anemia, lessons learned from antenatal iron-folic acid (IFA) supplementation can inform new micronutrient supplementation efforts. The World Health Organization recommends calcium supplementation for the prevention of preeclampsia; however, little is documented on how to design programs to integrate calcium into the standard of care. Twenty interviews with pregnant women and 22 interviews with health providers and volunteers in two districts in Ethiopia were conducted to examine how barriers and facilitators to antenatal care, IFA supplementation, and initial reactions to calcium supplements and regimen might influence adherence and inform future programs. Women viewed supplementation positively but cited lack of information on benefits and risks, forgetfulness, and inconsistent IFA supply as challenges. Though knowledge and awareness of anemia and IFA supplements were widespread, preeclampsia was mostly unknown. Some symptoms of preeclampsia were viewed as normal in pregnancy, making it difficult to convey risk to motivate supplement use. Some women viewed co-consumption of IFA and calcium as potentially harmful and were confused regarding the simultaneous risks of anemia and hypertension, understood as "low" and "high" blood levels in pregnancy. However, most said they would take both IFA and calcium supplements if provided with supplements and counseling on purpose and benefits. Strategies such as social support from families, stronger community-based counseling, and increased health care provider and community awareness of preeclampsia are critical for women to understand the benefits of supplementation and resolve confusion caused by current descriptors used for anemia and hypertension.

Body mass index, calcium supplementation and risk of colorectal adenomas

Calcium supplementation (1,200 mg/day) did not significantly reduce colorectal adenomas in our recent randomized, controlled trial (Vitamin D/Calcium Polyp Prevention Study, VCPPS, 2004-2013) in contrast to our previous trial (Calcium Polyp Prevention Study, CPPS, 1988-1996). To reconcile these findings, we identified participant characteristics that differed between the study populations and modified the effect of calcium supplementation on adenomas or high-risk findings (advanced or multiple adenomas). Compared to the CPPS, more participants in the VCPPS were obese (body mass index (BMI) ≥30 kg/m² ; 37.5% vs. 24.4%) and fewer had normal BMI (BMI <25 kg/m² ; 18.5% vs. 31%). BMI appeared to modify the effect of calcium supplementation on adenomas and especially on high risk-findings: in the VCPPS, there was a 44% reduction in high-risk findings among individuals whose BMI was normal (RR = 0.56, 95% CI = 0.26-1.23), but not among overweight (RR = 1.09, 95% CI = 0.62-1.91) or obese (RR = 1.54, 95% CI = 0.92-2.57) individuals (p_interaction = 0.03). Similarly, in the CPPS, there was a 56% reduction in high-risk findings among individuals whose BMI was normal (RR = 0.44, 95% CI = 0.26-0.74), but not among overweight (RR = 0.87, 95% CI = 0.55-1.39) or obese (RR = 1.02, 95% CI = 0.57-1.82) individuals (p_interaction = 0.02). Standardization of each trial's findings to the BMI distribution in the other attenuated calcium's protective effect on adenomas in the CPPS but enhanced it in the VCPPS. In conclusion, 1,200 mg/day calcium supplementation may reduce risk of colorectal adenomas among those with normal BMI but not in overweight or obese individuals; and differences in BMI distribution partially account for the apparent difference in calcium efficacy between the two trials.

Fortified tuna bone powder supplementation increases bone mineral density of lactating rats and their offspring

BACKGROUND

Breastfeeding leads to bone calcium loss for milk production, resulting in progressive maternal osteopenia. Calcium supplement from natural sources has been postulated to be more beneficial to bone health than purified CaCO₃ because natural sources also contain other nutrients such as certain amino acids that might enhance calcium metabolism. Herein, we examined the effect of calcium supplementation from tuna bone powder and CaCO₃ on bones of dams and the offspring.

RESULTS

Both forms of calcium supplement, i.e. tuna bone powder and CaCO₃ , increased maternal bone mineral density (BMD). However, bone histomorphometry revealed that only tuna bone had beneficial effect on maternal bone microstructure, i.e. increased bone formation, decreased bone resorption and increased in bone volume. Regarding the mechanical properties, the decreased ultimate load in non-supplement lactating mothers was restored to the load seen in nulliparous animals by calcium supplementation. Moreover, both tuna bone and CaCO₃ supplementation in mothers led to increased milk calcium concentration and consequently increased BMD in the growing offspring.

CONCLUSION

Calcium supplement from tuna bone powder was effective in preventing maternal osteopenia. Tuna bone, which is a readily available fishing industrial waste, is a good alternative source of calcium supplement that increases BMD in both lactating mothers and the neonates. © 2017 Society of Chemical Industry.

Field trial of 2 calcium supplements on early lactation health and production in multiparous Holstein cows

Our objectives were to measure serum Ca concentrations in the first 48 h postpartum in cows supplemented with oral Ca or subcutaneous Ca and nonsupplemented cows and evaluate the effect of these treatments on the incidence of metritis, displaced abomasum, mastitis, and early lactation disease (any of the diseases milk fever, retained placenta, metritis, or displaced abomasum), removal from the herd, pregnancy to first insemination, and average daily milk yield for the first 10 wk of lactation. We conducted 2 experiments on 1 commercial herd in New York State. In experiment 1, multiparous Holstein cows (n = 30) were blocked by parity (2 and ≥3) and sequentially assigned at calving to nontreated control (CON, n = 10), subcutaneous administration of 500 mL 23% Ca gluconate at calving (SC, n = 10), or administration of an oral Ca bolus containing 43 g of calcium at calving and again 12 h later (OB, n = 10). Blood was collected before treatment and at 1, 2, 4, 8, 12, 24, and 48 h thereafter for measurement of serum total Ca concentration. In experiment 2, 1,478 multiparous Holstein cows were sequentially assigned by calving date to the same 3 treatments (CON, n = 523; SC, n = 480; OB, n = 475). In experiment 1, SC cows had greater Ca concentrations from 1 through 12 h post-treatment and OB cows had greater Ca concentrations at 1 and 24 h post-treatment compared with CON cows. We found no difference in risk of metritis, displaced abomasum, early lactation disease diagnosis, or pregnancy to first insemination among treatments. Treatment with SC or OB had no effect on average daily milk yield compared with CON cows (CON = 46.7 kg; SC = 47.1 kg; OB = 47.0 kg). Cows treated with SC or OB that had a high relative herd milk rank in the previous lactation were almost half as likely to be diagnosed with mastitis in the first 60 DIM compared with CON cows [risk ratio (RR)_SC = 0.57, RR_OB = 0.54]; however, we found no difference in risk of mastitis among treatments for cows with low relative herd milk rank. Second-parity cows fed a negative prepartum dietary cation-anion difference ration and treated with SC or OB were more likely to be removed from the herd than CON cows (RR_SC = 3.91, RR_OB = 4.72); this difference was not observed in second-parity cows fed a neutral prepartum dietary cation-anion difference ration or in parity ≥3 cows. Although Ca supplementation increased serum Ca, this effect did not greatly improve milk production or health and reproductive outcomes.

A Simplified Regimen Compared with WHO Guidelines Decreases Antenatal Calcium Supplement Intake for Prevention of Preeclampsia in a Cluster-Randomized Noninferiority Trial in Rural Kenya

Background: To prevent preeclampsia, the WHO recommends antenatal calcium supplementation in populations with inadequate habitual intake. The WHO recommends 1500-2000 mg Ca/d with iron-folic acid (IFA) taken separately, a complex pill-taking regimen. Objective: The objective of this study was to test the hypothesis that simpler regimens with lower daily dosages would lead to higher adherence and similar supplement intake.Methods: In the Micronutrient Initiative Calcium Supplementation study, we compared the mean daily supplement intake associated with 2 dosing regimens with the use of a parallel, cluster-randomized noninferiority trial implemented in 16 primary health care facilities in rural Kenya. The standard regimen was 3 × 500 mg Ca/d in 3 pill-taking events, and the low-dose regimen was 2 × 500 mg Ca/d in 2 pill-taking events; both regimens included a 200 IU cholecalciferol and calcium pill and a separate IFA pill. We enrolled 990 pregnant women between 16 and 30 wk of gestation. The primary outcome was supplemental calcium intake measured by pill counts 4 and 8 wk after recruitment. We carried out intention-to-treat analyses with the use of mixed-effect models, with regimen as the fixed effect and health care facilities as a random effect, by using a noninferiority margin of 125 mg Ca/d.Results: Women in facilities assigned to the standard regimen consumed a mean of 1198 mg Ca/d, whereas those assigned to the low-dose regimen consumed 810 mg Ca/d. The difference in intake was 388 mg Ca/d (95% CI = 341, 434 mg Ca/d), exceeding the prespecified margin of 125 mg Ca/d. The overall adherence rate was 80% and did not differ between study arms.Conclusions: Contrary to our expectation, a simpler, lower-dose regimen led to significantly lower supplement intake than the regimen recommended by the WHO. Further studies are needed to precisely characterize the dose-response relation of calcium supplementation and preeclampsia risk and to examine cost effectiveness of lower and simpler regimens in program settings. This trial was registered at clinicaltrials.gov as NCT02238704.

Should women be advised to use calcium supplements during pregnancy? A decision analysis

Adequate calcium intake during pregnancy is important in the prevention of pre-eclampsia. A substantial proportion of pregnant women do not meet the recommended daily calcium intake, even in developed countries. Nonetheless, calcium supplementation is not routinely advised to pregnant women in most countries. We aimed to predict the impact of advising pregnant women to use calcium supplements (1,000 mg/day) on the number of cases of pre-eclampsia prevented and related health care costs. By use of a decision-analytic model, we assessed the expected impact of advising calcium supplementation to either (1) all pregnant women, (2) women at high risk of developing pre-eclampsia, or (3) women with a low dietary calcium intake compared with current care. Calculations were performed for a hypothetical cohort of 100,000 pregnant women living in a high-income country, although input parameters of the model can be adjusted so as to fit other settings. The incidence of pre-eclampsia could be reduced by 25%, 8%, or 13% when advising calcium supplementation to all pregnant women, women at high risk of pre-eclampsia, or women with a low dietary calcium intake, respectively. Expected net financial benefits of the three scenarios were of €4,621,465, €2,059,165, or €2,822,115 per 100,000 pregnant women, respectively. Advising pregnant women to use calcium supplements can be expected to cause substantial reductions in the incidence of pre-eclampsia as well as related health care costs. It appears most efficient to advise calcium supplementation to all pregnant women, not subgroups only.

A case report: hypercalcemia due to vitamin supplementation in a patient with neurofibromatosis

A 54-year-old female with history of neurofibromatosis who presented with severe hypercalcemia and renal failure secondary to over supplementation of calcium and vitamin D.

Hypochlorhydria-induced calcium malabsorption does not affect fracture healing but increases post-traumatic bone loss in the intact skeleton

Efficient calcium absorption is essential for skeletal health. Patients with impaired gastric acidification display low bone mass and increased fracture risk because calcium absorption is dependent on gastric pH. We investigated fracture healing and post-traumatic bone turnover in mice deficient in Cckbr, encoding a gastrin receptor that affects acid secretion by parietal cells. Cckbr-/- mice display hypochlorhydria, calcium malabsorption, and osteopenia. Cckbr-/- and wildtype (WT) mice received a femur osteotomy and were fed either a standard or calcium-enriched diet. Healed and intact bones were assessed by biomechanical testing, histomorphometry, micro-computed tomography, and quantitative backscattering. Parathyroid hormone (PTH) serum levels were determined by enzyme-linked immunosorbent assay. Fracture healing was unaffected in Cckbr-/- mice. However, Cckbr-/- mice displayed increased calcium mobilization from the intact skeleton during bone healing, confirmed by significantly elevated PTH levels and osteoclast numbers compared to WT mice. Calcium supplementation significantly reduced secondary hyperparathyroidism and bone resorption in the intact skeleton in both genotypes, but more efficiently in WT mice. Furthermore, calcium administration improved bone healing in WT mice, indicated by significantly increased mechanical properties and bone mineral density of the fracture callus, whereas it had no significant effect in Cckbr-/- mice. Therefore, under conditions of hypochlorhydria-induced calcium malabsorption, calcium, which is essential for callus mineralization, appears to be increasingly mobilized from the intact skeleton in favor of fracture healing. Calcium supplementation during fracture healing prevented systemic calcium mobilization, thereby maintaining bone mass and improving fracture healing in healthy individuals whereas the effect was limited by gastric hypochlorhydria. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1914-1921, 2016.

Increased Calcium Supplementation Postpartum Is Associated with Breastfeeding among Chinese Mothers: Finding from Two Prospective Cohort Studies

The calcium supplementation status during the postpartum period among Chinese lactating women is still unclear. The objective of this study is to utilize data from two population-based prospective cohort studies to examine the calcium supplementation status and to identify whether breastfeeding is associated with increased calcium supplementation among Chinese mothers after child birth. Information from 1540 mothers on breastfeeding and calcium supplementation measured at discharge, 1, 3, and 6 months postpartum were extracted to evaluate the association between breastfeeding and calcium supplementation postpartum. A generalized linear mixed model was applied to each study initially to account for the inherent correlation among repeated measurements, adjusting for socio-demographic, obstetric factors and calcium supplementation during pregnancy. In addition, breastfeeding status measured at different follow-up time points was treated as a time dependent variable in the longitudinal analysis. Furthermore, the effect sizes of the two cohort studies were pooled using fixed effect model. Based on the two cohort studies, the pooled likelihood of taking calcium supplementation postpartum among breastfeeding mothers was 4.02 times (95% confidence interval (2.30, 7.03)) higher than that of their non-breastfeeding counterparts. Dietary supplementation intervention programs targeting different subgroups should be promoted in Chinese women, given currently a wide shortage of dietary calcium intake and calcium supplementation postpartum.

Patterns of Non-adherence to Supplementation with Calcium and Vitamin D in Persistent Postmenopausal Women Are Similar at Start and 1 Year Later: A Qualitative Longitudinal Study

Background: Osteoporosis is a chronic disease and adherence can fluctuate over time. Therefore, longer observation is necessary to investigate the stability of patients' adherence. The study aim was to compare the overall adherence (OA) to supplementation with the fixed combination of calcium and vitamin D (Ca/D) in postmenopausal women at baseline and after 1 year, and to evaluate the fluctuation of the OA in individual months. Furthermore, we studied whether adherence is influenced by signing of informed consent and routine medical check-up.

Methods: This was a longitudinal, observational study. The data were obtained from the Osteocenter of University Hospital in Hradec Kralove, Czech Republic. Adherence was measured using electronic bottles type Medication Events Monitoring System (MEMS). The study was carried out in two 3-month periods; the baseline in 2013 (signing of informed consent while medical check-up) and the follow-up (medical check-up) in 2014. The adherence and adherence-related outcomes were studied in patients who had initiated osteoporosis treatment and were persistent.

Results: 21 (49%) out of 43 patients who avoided drug dispenser and were persistent both at baseline and at follow-up, completed the study and were included. Median age was 76. Evaluating the whole 3-month periods, the OA did not differ significantly at baseline and at follow-up, the OA was 71 and 68%, respectively. However, the adherence in month 1 at baseline was significantly higher than the adherence in month 2 at baseline (p < 0.001) and also than the adherence in month 1 at follow-up (p = 0.010). Analysing the study period without month 1, a stable adherence was observed in 48% of patients. About 33% of doses were omitted at baseline and 34% at follow-up. As many as 71% of the patients took drug holidays at baseline, and 76% at follow-up.

Conclusion: The OA was insufficient, around 70% both at baseline and at follow-up. One half of the patients showed a stable adherence. The patterns of non-adherence were very similar at follow-up. Signing of the informed consent seems to act as bias more than regular medical check-up.

Milk hypersensitivities: where is the grey line regarding their dietary management?

The proportion of people suffering or reporting to have a hypersensitivity caused by cow's milk consumption is increasing, and even health professionals often face difficulties into elaborating properly with a milk reaction due to misdiagnosis. The scope of this review is to present literature data that lead into putting the border line between cow's milk allergy and cow's milk intolerance, mainly focusing on how the different pathophysiology leads to their different dietary diagnosis and management.

Effects of oral calcium supplementation on productive and reproductive performance in Holstein cows

The objectives of this experiment were to determine the effects of oral Ca supplementation on milk yield, body condition, pregnancy per artificial insemination (P/AI), and days to pregnancy in Holstein cows considered to be of low (LRM; no calving assistance, live singleton without retained placenta) or high (HRM; at least one of the following: dystocia, twins, stillbirth, retained placenta, or vulvo-vaginal laceration) risk of developing metritis. The hypotheses were that oral Ca supplementation during the early postpartum period would reduce the loss of body condition and improve lactation performance and reproduction. Four hundred fifty Holstein cows were blocked by parity as primiparous cows (n=174) or multiparous cows (n=276). Within parity, a cow considered at HRM was matched with a cow of LRM and the pair was randomly assigned to control (no Ca supplementation), 86g of Ca on d 0 and 1 postpartum (CaS1), or 86g of Ca on d 0 and 1 postpartum followed by 43g/d on d 2 to 4 postpartum (CaS4). Body condition was scored at calving and 32 d postpartum and estrous cyclicity was evaluated at 38 and 52 d postpartum. Milk yield was recorded daily. Multiparous cows were classified as above or below the mean 305-d mature equivalent milk yield based on production in the previous lactation. Reproductive performance was evaluated for the first 210 d postpartum. Body condition did not differ among treatments, and cows lost on average 0.44 units of body condition in the first month of lactation. Calcium supplementation did not affect milk yield in the first 5 mo postpartum. For multiparous cows, Ca supplementation was beneficial to milk yield in the first 30 DIM in cows of greater production potential, but detrimental to multiparous cows with below average production potential. Calcium supplementation to primiparous cows reduced P/AI at first (control=55.8, CaS1=31.5, CaS4=37.0%) and all artificial inseminations (control=48.5, CaS1=34.6, CaS4=38.5%); however, Ca supplementation to multiparous cows improved P/AI at the first (control=32.1, CaS1=38.6, CaS4=41.3%) and all artificial inseminations (control=28.1, CaS1=35.3, CaS4=40.5%). These responses in P/AI to Ca supplementation resulted in extended median days to pregnancy (control=75, CaS1=100, CaS4=94 d) and smaller proportion of pregnant cows (control=89.3, CaS1=83.9, CaS4=83.9%) in primiparous cows, but shorter days to pregnancy (control=115, CaS1=94, CaS4=94 d) and increased proportion of pregnant cows in multiparous cows (control=67.0, CaS1=77.2, CaS4=74.3%). Risk of metritis depressed most measures of reproduction evaluated in the experiment. Results indicate that responses to oral Ca supplementation are conditional on parity and production potential of cows. Oral Ca supplementation was detrimental to reproduction in primiparous cows. On the other hand, Ca supplementation benefited reproduction in multiparous cows and milk yield in the cohort of multiparous cows of greater production potential.

Calcium reduces vitamin D and glucocorticoid receptors in the visceral fat of obese male rats

Rats overfed during lactation show higher visceral adipose tissue (VAT) mass and metabolic dysfunctions at adulthood. As both vitamin D and glucocorticoids change adipogenesis, parameters related to metabolism and action of these hormones in the adipocyte can be altered in rats raised in small litters (SL). We also studied the antiobesity effects of high calcium diet since it decreases visceral fat in obesity models. On postnatal day (PN) 3, litter size was adjusted to 3pups/dam (SL) to induce overfeeding. Control litters (NL) remained with 10pups/dam until weaning. From PN120 to PN180, half of the SL rats were fed standard chow (SL) and the other half was fed a calcium-supplemented chow (SL-Ca, 10g CaCO3/kg). Both SL groups were heavier and hyperphagic when compared with the NL group; however, SL-Ca rats ate less than SL. SL-Ca rats had decreased VAT mass and adipocyte size, associated with lower hypothalamic NPY content, VAT fat acid synthase content and leptinemia. At PN120, SL rats had increased plasma 25(OH)D3, Cyp27b1 mRNA and glucocorticoid receptor (GR-α) in the VAT, but lower vitamin D receptor (Vdr) mRNA. At PN180, Cyp27b1 and GR-α remained higher, while Vdr normalized in SL rats. SL-Ca rats had normal VAT Cyp27b1 and GR-α, but lower Vdr Thus, higher body mass and glucocorticoid receptors in the VAT of SL rats are normalized by calcium-enriched diet, and Vdr expression in this tissue is reduced, suggesting a possible role of glucocorticoids and vitamin D in calcium action in the adipocyte.

Calcium intake: good for the bones but bad for the heart? An analysis of clinical studies

The proper dietary calcium intake and calcium supplementation, when indicated, are important factors in the acquisition of peak bone mass during youth and in the prevention of fractures in old age. In addition to its deposition in bone, calcium confers an increase in its resistance and exhibits important activities in different enzymatic pathways in the body (e.g., neural, hormonal, muscle-related and blood clotting pathways). Thus, calcium supplementation can directly or indirectly affect important functions in the body, such as the control of blood pressure, plasma glucose, body weight, lipid profile and endothelial function. Since one publication reported increased cardiovascular risk due to calcium supplementation, many researchers have studied whether this risk actually exists; the results are conflicting, and the involved mechanisms are uncertain. However, studies that have evaluated the influence of the consumption of foods rich in calcium have reported no increase in the cardiovascular risk, which suggests that nutritional intake should be prioritized as a method for supplementation and that the use of calcium supplements should be reserved for patients who truly need supplementation and are unable to achieve the recommended daily nutritional intake of calcium.

Calcium intake and urinary stone disease

Calcium homeostasis is a complicated and incompletely understood process that is primarily regulated through an interaction between the intestines, kidneys, and bones. Intestinal calcium absorption is determined by many factors including the amount of regular calcium intake, as well as vitamin D and parathyroid hormone levels. Intestinal calcium absorption is likely different between stone formers and non-stone formers, with higher levels of calcium absorption in those with a history of stones independent of their calcium intake. We no longer recommend dietary calcium restriction as this may lead to bone demineralization and an increase in stone formation. Practitioners need to continue to educate patients to maintain moderate dietary calcium intake. The effect of calcium supplementation on stone formation is currently controversial. It is likely that large doses of supplemental calcium, especially if taken separate from a meal, may lead to stone formation. When necessary, stone forming patients should be encouraged to take their calcium supplements with a meal and their stone disease should be monitored.

Long-term changes in brain cholinergic system and behavior in rats following gestational exposure to lead: protective effect of calcium supplement

Our earlier studies showed that lactational exposure to lead (Pb) caused irreversible neurochemical alterations in rats. The present study was carried out to examine whether gestational exposure to Pb can cause long-term changes in the brain cholinergic system and behavior of rats. The protective effect of calcium (Ca) supplementation against Pb toxicity was also examined. Pregnant rats were exposed to 0.2% Pb (Pb acetate in drinking water) from gestational day (GD) 6 to GD 21. The results showed decrease in body weight gain (GD 6-21) of dams, whereas no changes were observed in offspring body weight at different postnatal days following Pb exposure. Male offspring treated with Pb showed marginal alterations in developmental landmarks such as unfolding of pinnae, lower and upper incisor eruption, fur development, eye slit formation and eye opening on postnatal day (PND) 1, whereas significant alterations were found in the righting reflex (PNDs 4-7), slant board behavior (PNDs 8-10) and forelimb hang performance (PNDs 12-16). Biochemical analysis showed decrease in synaptosomal acetylcholinesterase (AChE) activity and an increase in acetylcholine (ACh) levels in the cortex, cerebellum and hippocampus on PND 14, PND 21, PND 28 and in the four-month age group of rats following Pb exposure. Significant deficits were also observed in total locomotor activity, exploratory behavior and open field behavior in selected age groups of Pb-exposed rats. These alterations were found to be maximal on PND 28, corresponding with the greater blood lead levels observed on PND 28. Addition of 0.02% Ca to Pb reversed the Pb-induced impairments in the cholinergic system as well as in behavioral parameters of rats. In conclusion, these data suggest that gestational exposure to Pb is able to induce long-term changes in neurological functions of offspring. Maternal Ca administration reversed these neurological effects of Pb later in life, suggesting a protective effect of calcium in Pb-exposed animals.

Calcium Supplements and Cardiovascular Disease: A Review

Dietary or supplemental calcium intake has long been encouraged for optimal bone health. However, more recently, the safety of calcium supplementation has been questioned because of a possible association between supplemental calcium and cardiovascular risk. Whereas calcium may have a beneficial or neutral effect on cardiovascular risk factors such as blood pressure, cholesterol, weight, and diabetes, available evidence does not provide a definitive answer for an association with cardiovascular disease (CVD). To date, no calcium trials have studied cardiovascular disease as a primary end point, and larger trials with longer follow-up are needed. In this review, we present results from observational studies and randomized controlled trials (RCTs) that have evaluated calcium intake (dietary or supplemental) in relation to cardiovascular risk factors and cardiovascular disease as a secondary outcome. Results from RCTs are mixed regarding CVD risk in those using supplemental calcium with or without vitamin D, and more large-scale randomized trials designed specifically with CVD as the primary end point are needed. Evidence suggests that it is reasonable to encourage adequate dietary calcium intake, especially for postmenopausal women who are at greatest risk for osteoporotic fracture.

Core-Shell Collagen Peptide Chelated Calcium/Calcium Alginate Nanoparticles from Fish Scales for Calcium Supplementation

We report simple methods for preparing collagen peptide chelated calcium (cpcc) and a novel cpcc-loaded nanoparticle from marine fish scales for calcium supplementation. Cpcc nanoparticles have an average diameter of approximately 150 nm and a calcium content of up to 130.4 g/kg. Calcium alginate was selected to encapsulate cpcc for the preparation of core-shell cpcc/calcium alginate nanoparticles. The core-shell nanoparticles were mainly 200 to 500 nm in diameter. The ratio of calcium to sulfur was approximately 1.6:1. In vivo experiments indicated both cpcc and core-shell cpcc were able to improve calcium absorption and prevent calcium deficiency. Especially core-shell cpcc worked well to increase femur bone mineral density and femur calcium content in rats significantly. The study demonstrated that cpcc and core-shell cpcc nanoparticles were ideal for calcium supplementation.

PRACTICAL APPLICATION

Calcium deficiency has become an increasingly relevant health concern in the food industry. There is an urgent need for new effective calcium supplements. This study consisted of preparing and characterizing alginate nanoparticles loaded with collagen peptide chelated calcium. These nanoparticles can enhance calcium absorption significantly and prevent calcium deficiency. The data presented in this study can aid the food industry in developing a new ideal calcium supplement.

Drug holidays: the most frequent type of noncompliance with calcium plus vitamin D supplementation in persistent patients with osteoporosis

PURPOSE

All current recommendations include calcium and vitamin D (Ca-D) as an integrated part of osteoporosis treatment. The purpose of this pilot study was to analyze compliance with a fixed combination of Ca-D in women persistent with the treatment.

PATIENTS AND METHODS

An observational study was carried out in three osteocenters in the Czech Republic. Women with osteoporosis ≥55 years of age concurrently treated with oral ibandronate were eligible. Compliance was evaluated in a period of 3 months by Medication Event Monitoring System (MEMS), tablet count, and self-report. Nonpersistence was defined as a MEMS-based gap in the use of Ca-D to be 30 days or more.

RESULTS

A total of 73 patients were monitored, of which 49 patients were analyzed (target population). Based on MEMS, mean overall compliance was 71%; good compliance (≥80%) was observed in 59% of the patients. As many as 71% of the patients took drug holidays (≥3 consecutive days without intake); overall compliance of these patients was 59% and was slightly lower on Fridays and weekends. Patients without drug holidays were fully compliant (did not omit individual doses). Compliance differed according to daily time at which the patients mostly used the Ca-D. Afternoon/evening takers showed a mean overall compliance of 82% while morning/night takers only 51% (P=0.049). Based on MEMS, tablet count, and self-report, compliance ≥75% was observed in 59%, 100%, and 87% of the patients, respectively. Outcomes obtained by the three methods were not associated with each other. Undesirable concurrent ingestion of Ca-D and ibandronate was present only twice.

CONCLUSION

Despite almost perfect self-reported and tablet count-based compliance, MEMS-based compliance was relatively poor. Consecutive supplementation-free days were common; more than two-thirds of the patients took at least one drug holiday. This pilot study showed drug holiday to be the most important type of noncompliance with Ca-D in those who are persistent with the treatment.

The problem of osteoporosis in epileptic patients taking antiepileptic drugs

INTRODUCTION

Epilepsy is a common neurological disorder associated with recurrent seizures. Therapy with antiepileptic drugs (AEDs) helps achieve seizure remission in approximately 70% of epileptic patients. Treatment with AEDs is frequently lifelong and there are reports suggesting its negative influence on bone health. This is especially important in terms of general occurrence of osteoporosis, affecting over 50 million people worldwide.

AREAS COVERED

This study refers to two main groups of AEDs: hepatic enzyme inducers (carbamazepine, oxcarbazepine, phenobarbital, phenytoin, primidone and topiramate) and non-inducers (clobazam, clonazepam, ethosuximide, gabapentin, lacosamide, lamotrigine, levetiracetam, pregabalin, tiagabine, valproate, vigabatrin and zonisamide). Some reports indicate that enzyme inducers may exert a more negative influence on bone mineral density (BMD) compared to non-inducers. Bone problems may appear in both sexes during AED therapy, although women are additionally burdened with postmenopausal osteoporosis. Supplementation of vitamin D and calcium in patients on AEDs is recommended.

EXPERT OPINION

Apart from enzyme inducers, valproate (an even enzyme inhibitor) may also negatively affect BMD. However, the untoward effects of AEDs may depend upon their doses and duration of treatment. Although the problem of supplementation of vitamin D and calcium in epileptic patients on AEDs is controversial, there are recommendations to do so.

Evaluation of calcium supplementation with algae (Lithothamnion muelleri) on metabolic and inflammatory parameters in mice fed a high refined carbohydrate-containing diet

The aim of the present study was to evaluate the potential of calcium supplementation from Lithothamnium muelleri algae on metabolic and inflammatory parameters in mice with increased adiposity. Male mice were fed and divided during 8 weeks in: control (C), a high refined carbohydrate-containing diet (HC), HC diet supplemented with 1% of Lithothamnion muelleri algae (HC + A) and HC diet supplemented with 0.9% calcium carbonate (HC + C). Animals fed HC diet had increased body weight gain and adiposity, serum glucose and cholesterol, glucose intolerance and decreased insulin sensitivity, compared to control diet. However, the HC + A and HC + C groups did not prevent these aspects and were not able to change the CD14 + cells population in adipose tissue of animals fed HC diet. Calcium supplementation with Lithothamnium muelleri algae and calcium carbonate had no protective effect against the development of adiposity, metabolic and inflammatory alterations induced by HC diet.

Calcium ameliorates diarrhea in immunocompromised children

Treatment of infectious diarrheas remains a challenge, particularly in immunocompromised patients in whom infections usually persist and resultant diarrhea is often severe and protracted. Children with infectious diarrhea who become dehydrated are normally treated with oral or intravenous rehydration therapy. Although rehydration therapy can replace the loss of fluid, it does not ameliorate diarrhea. Thus, during the last decades, there has been continuous effort to search for ways to safely stop diarrhea. Herein, we report 3 immunocompromised children who developed severe and/or protracted infectious diarrhea. Their diarrheas were successfully "halted" within 1 to 2 days following the administration of calcium.

Hot flashes in breast cancer survivors and an association with calcium supplement use

AIMS

In breast cancer survivors, we aimed to describe the frequency of hot flashes and night sweats, frequency and type of treatment, and the association of hot flashes and use of calcium supplements.

METHODS

Charts of breast cancer survivors were reviewed for information about hot flashes, treatment for hot flashes, and calcium supplementation. Associations between variables were explored using the Chi-square test and Fisher's Exact test.

RESULTS

Eighty-six charts were reviewed. Mean age of the women was 58 years and 79% were postmenopausal. Forty-two (49%) of women had hot flashes and 18 (21%) had night sweats. Thirty-one (36%) were treated for hot flashes. Treatment included selective serotonin reuptake inhibitors/serotonin-norepinephrine reuptake inhibitors (n = 19), clonidine (n = 7), Bellergal-S(®) (n = 8), sleep-aid (n = 7), and other (n = 5). Calcium supplementation was recorded in 31%. Of women with hot flashes, 44% took calcium supplements; of women without hot flashes, 18% took calcium supplements (Chi-square P = 0.02).

CONCLUSION

Hot flashes were recorded in 49% of this group of primarily postmenopausal breast cancer survivors. Women with hot flashes were more likely to be taking calcium supplements. Further exploration of the association between hot flashes and calcium supplementation is warranted.

Is excess calcium harmful to health?

Most current guidelines recommend that older adults and the elderly strive for a total calcium intake (diet and supplements) of 1,000 to 1,300 mg/day to prevent osteoporosis and fractures. Traditionally, calcium supplements have been considered safe, effective and well tolerated, but their safety has recently been questioned due to potential adverse effects on vascular disease which may increase mortality. For example, the findings from a meta-analysis of randomized controlled trials (currently published in abstract form only) revealed that the use of calcium supplements was associated with an ~30% increased risk of myocardial infarction. If high levels of calcium are harmful to health, this may alter current public health recommendations with regard to the use of calcium supplements for preventing osteoporosis. In this review, we provide an overview of the latest information from human observational and prospective studies, randomized controlled trials and meta-analyses related to the effects of calcium supplementation on vascular disease and related risk factors, including blood pressure, lipid and lipoprotein levels and vascular calcification.

Predictors of adherence in the Women's Health Initiative Calcium and Vitamin D Trial

The authors analyzed data from the Women's Health Initiative (WHI) Calcium and Vitamin D Supplementation Trial (CaD) to learn more about factors affecting adherence to clinical trial study pills (both active and placebo). Most participants (36,282 postmenopausal women aged 50-79 years) enrolled in CaD 1 year after joining either a hormone trial or the dietary modification trial of WHI. The WHI researchers measured adherence to study pills by weighing the amount of remaining pills at an annual study visit; adherence was primarily defined as taking > or = 80% of the pills. The authors in this study examined a number of behavioral, demographic, procedural, and treatment variables for association with study pill adherence. They found that relatively simple procedures (ie, phone contact early in the study [4 weeks post randomization] and direct social contact) later in the trial may improve adherence. Also, at baseline, past pill-use experiences, personal supplement use, and relevant symptoms may be predictive of adherence in a supplement trial.

Efficacy of different doses and time intervals of oral vitamin D supplementation with or without calcium in elderly nursing home residents

The effect of equivalent oral doses of vitamin D3 600 IU/day, 4200 IU/week and 18,000 IU/month on vitamin D status was compared in a randomized clinical trial in nursing home residents. A daily dose was more effective than a weekly dose, and a monthly dose was the least effective.

INTRODUCTION

It is assumed that equivalent daily, weekly or monthly doses of vitamin D3 equally influence vitamin D status. This was investigated in a randomized clinical trial in nursing home residents.

METHODS

The study was performed in ten nursing homes including 338 subjects (76 male and 262 female), with a mean age of 84 (+/- SD 6.3 years). They received oral vitamin D3 either 600 IU/day, or 4200 IU/week, or 18,000 IU/month or placebo. After 4 months, calcium was added during 2 weeks, 320 mg/day or 640 mg/day or placebo.

OUTCOME

serum levels of 25-hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH) and bone turnover markers. Statistical approach: linear multilevel analysis.

RESULTS

At baseline, mean serum 25(OH)D was 25.0 nmol/L (SD 10.9), and in 98%, it was lower than 50 nmol/L. After 4 months, mean serum 25(OH)D levels increased to 62.5 nmol/L (after daily vitamin D3 69.9 nmol/L, weekly 67.2 nmol/L and monthly 53.1 nmol/L, P < 0.001 between groups). Median serum PTH levels decreased by 23% (p < 0.001). Bone turnover markers did not decrease. Calcium supplementation had no effect on serum PTH and bone turnover.

CONCLUSION

Daily vitamin D was more effective than weekly, and monthly administration was the least effective.

Health-behavior induced disease: return of the milk-alkali syndrome

The milk-alkali syndrome is a well-documented consequence of excessive calcium and alkali intake first recognized in association with early 20th century antacid regimens. The syndrome became rare after widespread implementation of modern peptic ulcer disease therapies. With recent trends in osteoporosis therapy coupled with widely available calcium-containing supplements, the milk-alkali syndrome has reemerged as an important clinical entity. Our case illustrates a patient who self-medicated his peptic ulcer disease with a regimen resembling a common early 20th century dyspepsia regimen. When superimposed upon chronic high calcium supplementation, the patient became acutely ill from the milk-alkali syndrome. When taken to excess, or used inappropriately, medications and supplements ordinarily considered beneficial, can have harmful effects. Our case underscores the importance of obtaining a thorough medication history including use of over-the-counter supplementation.

Blood lead changes during pregnancy and postpartum with calcium supplementation

Pregnancy and lactation are times of physiologic stress during which bone turnover is accelerated. Previous studies have demonstrated that there is increased mobilization of lead from the maternal skeleton at this time and that calcium supplementation may have a protective effect. Ten immigrants to Australia were provided with either calcium carbonate or a complex calcium supplement (approximately 1 g/day) during pregnancy and for 6 months postpartum. Two immigrant subjects who did not conceive acted as controls. Sampling involved monthly venous blood samples throughout pregnancy and every 2 months postpartum, and quarterly environmental samples and 6-day duplicate diets. The geometric mean blood lead at the time of first sampling was 2.4 microg/dL (range, 1.4-6.5). Increases in blood lead during the third trimester, corrected for hematocrit, compared with the minimum value observed, varied from 10 to 50%, with a geometric mean of 25%. The increases generally occurred at 6-8 months gestation, in contrast with that found for a previous cohort, characterized by very low calcium intakes, where the increases occurred at 3-6 months. Large increases in blood lead concentration were found during the postpartum period compared with those during pregnancy; blood lead concentrations increased by between 30 and 95% (geometric mean 65%; n = 8) from the minimum value observed during late pregnancy. From late pregnancy through postpartum, there were significant increases in the lead isotopic ratios from the minimum value observed during late pregnancy for 3 of 8 subjects (p < 0.01). The observed changes are considered to reflect increases in mobilization of lead from the skeleton despite calcium supplementation. The identical isotopic ratios in maternal and cord blood provide further confirmation of placental transfer of lead. The extra flux released from bone during late pregnancy and postpartum varies from 50 to 380 microg lead (geometric mean, 145 microg lead) compared with 330 microg lead in the previous cohort. For subjects replete in calcium, the delay in increase in blood lead and halving of the extra flux released from bone during late pregnancy and postpartum may provide less lead exposure to the developing fetus and newly born infant. Nevertheless, as shown in several other studies on calcium relationships with bone turnover, calcium supplementation appears to provide limited benefit for lead toxicity during lactation.