Calcium intake is not associated with increased coronary artery calcification: the Framingham Study

Associations of Dietary Calcium and Phosphorus With Vascular and Valvular Calcification: The ARIC Study

Background

High dietary calcium and phosphorus may accelerate vascular calcification, but epidemiological data are inconsistent. Most of those studies assessed diet at one point and have not been systematically evaluated.

Objectives

The purpose of this study was to assess the associations of dietary calcium and phosphorus intakes in middle age with coronary artery and extra-coronary calcification at older age.

Methods

We studied 1,914 participants from the ARIC (Atherosclerosis Risk In Communities) study (mean age 80.5 years) without coronary heart disease who underwent chest computed tomography scans at visit 7 (2018-2019) and completed a 66-item food frequency questionnaire at 2 earlier visits (visit 1 [1987-1989] and visit 3 [1993-1995]). Dietary calcium and phosphorus intakes were averaged between these 2 visits. Calcification was quantified by the Agatston score in coronary artery, ascending aorta, descending aorta, aortic valve ring, aortic valve, and mitral valve.

Results

Dietary calcium intake was inversely associated with coronary artery and ascending aorta calcification, whereas the association was not significant for other measures of extra-coronary calcification. For example, the highest vs lowest quartile of calcium intake showed an adjusted OR of 0.66 (95% CI: 0.45-0.98) for coronary artery calcification (Agatston score ≥75th percentile). Dietary phosphorus intake demonstrated similar results, but the magnitude of the association was weaker than dietary calcium intake.

Conclusions

Dietary calcium and phosphorus intakes at middle age were not positively associated with vascular and valvular calcification at over 75 years old. Our findings did not support the link between a calcium or phosphorus-rich diet and vascular and valvular calcification.

Association between serum calcium level and in-hospital mortality in patients with acute myocardial infarction: a retrospective cohort study

The association between serum calcium levels and the prognosis of patients with acute myocardial infarction (AMI) remains controversial. This study aimed to explore the association between serum calcium and in-hospital mortality in patients with AMI. The data of this study were extracted from the Philips eICU Collaborative Research Database. A total of 7284 patients were eventually enrolled in this study, of which 799 (10.97%) died during hospitalization. For each patient, serum calcium, corrected to albumin, was calculated and categorized into four groups: Q1 ≤ 8.5, Q2 8.5-9.5, Q3 9.5-10.5, and Q4 > 10.5 mg/dL. Multivariate analysis demonstrated that corrected sCa was an independent predictor of in-hospital death (Q2 vs. Q1, OR 0.5, 95% CI 0.4-0.7, P < 0.001; Q3 vs. Q1, OR 0.8, 95% CI 0.6-1.0, P = 0.035; Q4 vs. Q1, OR 1.6, 95% CI 1.1-2.3, P = 0.008). The association remained stable in the fully adjusted model. A significant U-shaped association between corrected serum calcium and in-hospital mortality was observed in piecewise linear regression model (Corrected sCa < 9.4 mg/dL, OR 0.8, 95% CI 0.7-0.9, P < 0.001; corrected sCa > 9.4 mg/dL, OR 1.5, 95% CI 1.3-1.8, P < 0.001). In conclusion, both decreased and increased corrected serum calcium is associated with increased in-hospital mortality in patients with AMI, and patients may have the lowest risk of in-hospital death when corrected serum calcium is 9.4 mg/dL (2.35 mmol/L).

Associations between bone mineral density and coronary artery calcification: a systematic review and meta-analysis

Background:

The studies about the correlation between bone mineral density (BMD) and coronary arterial calcification (CAC) were still controversial. The aim of this study was to conduct a meta-analysis to evaluate the association between BMD and CAC.

Methods:

We systematically searched PubMed, Embase, Google scholar and Cochrane library for observational studies. We pooled odds ratio (OR) or correlation coefficient, and 95% confidence interval (CI) of the studies. Continuous data were pooled by mean difference (MD). Sub-group analysis was applied to investigate sources of heterogeneity. Funnel plots for publication bias was also performed.

Results:

Seventeen studies met the inclusion criteria. Pooled ORs for the prevalence of CAC in patients with low BMD versus patients with normal BMD was 2.11 (95% CI: 1.11 - 4.02, P = 0.02). The data pooled for comparing CAC score of low BMD and normal BMD patients is 33.77 (95% CI: 23.77 - 43.77, p = 0.000). The pooled ORs of multivariate logistic regression to predict the association were 1.00 (95% CI: 0.92 - 1.10, p = 0.95, age-adjusted), and 0.95 (95% CI: 0.86 - 1.05, p = 0.33, multivariable-adjusted). Cohort category and BMD assessment method were the main sources of heterogeneity.

Conclusions:

Low BMD is associated with higher prevalence and severity of CAC, especially in postmenopausal women. But the relation is not significant after adjusting age and other confounding variables. Low BMD and CAC may be two independent processes with aging. More large-scale studies with high-quality design are still needed to increase the understanding of them.

Gut Microbiome, Functional Food, Atherosclerosis, and Vascular Calcifications-Is There a Missing Link?

The gut microbiome is represented by the genome of all microorganisms (symbiotic, potential pathogens, or pathogens) residing in the intestine. These ecological communities are involved in almost all metabolic diseases and cardiovascular diseases are not excluded. Atherosclerosis, with a continuously increasing incidence in recent years, is the leading cause of coronary heart disease and stroke by plaque rupture and intraplaque hemorrhage. Vascular calcification, a process very much alike with osteogenesis, is considered to be a marker of advanced atherosclerosis. New evidence, suggesting the role of dietary intake influence on the diversity of the gut microbiome in the development of vascular calcifications, is highly debated. Gut microbiota can metabolize choline, phosphatidylcholine, and L-carnitine and produce vasculotoxic metabolites, such as trimethylamine-N-oxide (TMAO), a proatherogenic metabolite. This review article aims to discuss the latest research about how probiotics and the correction of diet is impacting the gut microbiota and its metabolites in the atherosclerotic process and vascular calcification. Further studies could create the premises for interventions in the microbiome as future primary tools in the prevention of atherosclerotic plaque and vascular calcifications.

Lower Leg Arterial Calcifications Assessed by High-Resolution Peripheral Quantitative Computed Tomography in Hypoparathyroid and Pseudohypoparathyroid Patients

Hypoparathyroidism (HypoPT) and pseudohypoparathyroidism (PHP) are diseases with abnormal calcium and phosphate homeostasis and low and high PTH levels, respectively. It has been hypothesized that this could dispose to vascular calcifications and thereby perhaps also cardiovascular morbidity. The aim of this study was to assess lower leg arterial calcifications (LLAC) in patients with HypoPT or PHP. Using a cross-sectional design, we measured the LLAC using a high-resolution peripheral quantitative computed tomography (HR-pQCT) scanner in 72 patients with HypoPT and 25 patients with PHP and compared them with findings in 61 controls. LLAC were found in only two (3%) of the controls. Compared to the controls, LLAC were significantly more prevalent in patients with HypoPT (N = 12, [17%], p < 0.01) and PHP (N = 4, [16%], p < 0.04). Compared to the patients without calcifications, patients with calcifications had higher plasma calcium levels and a lower eGFR, as well as they were older and more often males. Plasma phosphate levels and the calcium-phosphate product were not associated with LLAC. In conclusion, we found that HypoPT and PHP are associated with an increased prevalence of vascular calcifications.

Extra-skeletal effects of dietary calcium: Impact on the cardiovascular system, obesity, and cancer

Calcium is well known to be integral to bone and muscle health, with deleterious effects such as osteoporosis associated with inadequate calcium intake. Recent studies have also highlighted the significant effects of calcium in extra-musculoskeletal functioning, including the cardiovascular system, obesity, and cancer. Calcium impacts the cardiovascular system as an antagonist associated with a reduction in hypertension, increase vasodilation, and improvement in blood vessel function when obtained in the diet as an organic source, through food. However, the inorganic source of calcium, found in supplements, may be negatively associated with the cardiovascular system due to plaque deposits and atherogenesis when taken in excess. Some studies suggest that calcium intake may impact obesity by regulation of adipogenesis and reducing fat deposits with resulting weight loss. The pathogenesis of calcium for reducing obesity is thought to be related in part to its impact on gut microbiota profile, with the suggestion that calcium may have prebiotic properties. Animal and some human studies propose that calcium may also have a role in cancer prevention and/or treatment due to its function in the cell proliferation process and the impact on hormonal regulation, and thus warrants more investigations in the human population. Some prospective and small clinical studies suggest that calcium may be beneficial for colorectal cancer. Overall, emerging research in various areas continues to highlight the essentiality of dietary calcium for functioning at the molecular and biochemical level toward improvement in health and some chronic disease conditions.

Oral Calcium Supplements Associate With Serial Coronary Calcification: Insights From Intravascular Ultrasound

OBJECTIVES

This study sought to evaluate and assess the extent of serial coronary artery calcification in response to oral calcium supplementation.

BACKGROUND

Oral calcium supplements are frequently used despite their cardiovascular safety remaining controversial. Their effects on serial coronary calcification are not well established.

METHODS

In a post hoc patient-level analysis of 9 prospective randomized trials using serial coronary intravascular ultrasound, changes in serial percentage of atheroma volume (PAV) and calcium indices (CaI) were compared in matched segments of patients coronary artery disease who were receiving concomitant calcium supplements (n = 447) and in those who did not receive supplements (n = 4,700) during an 18- to 24-month trial period.

RESULTS

Patients (mean age 58 ± 9 years; 73% were men; 43% received concomitant high-intensity statins) demonstrated overall annualized changes in PAV and CaI with a mean of -0.02 ± 1.9% (p = 0.44) and a median of 0.02 (interquartile range: 0.00 to 0.06) (p < 0.001) from baseline, respectively. Following propensity-weighted mixed modeling adjusting for treatment and a range of demographic, clinical, ultrasonic, and laboratory parameters (including but not limited to sex, race, baseline, and annualized change in PAV, baseline CaI, concomitant high-intensity statins, diabetes mellitus, renal function), there were no significant between-group differences in annualized changes in PAV (least-squares mean: 0.09; 95% confidence interval [CI]: -0.20 to 0.37 vs. 0.01; 95% CI: -0.27 to 0.29; p = 0.092) according to calcium supplement intake. Per a multivariable logistic regression model accounting for the range of covariates described, calcium supplementation independently associated with an increase in annualized CaI (odds ratio: 1.15; 95% CI: 1.05 to 1.26; p = 0.004).

CONCLUSIONS

Oral calcium supplementation may increase calcium deposition in the coronary vasculature independent of changes in atheroma volume. The impact of these changes on plaque stability and cardiovascular outcomes requires further investigation.

Pharmacological and Nutritional Modulation of Vascular Calcification

Vascular calcification is an independent predictor of cardiovascular disease, and therefore, inhibition or regression of this processes is of clinical importance. The standard care regarding prevention and treatment of cardiovascular disease at this moment mainly depends on drug therapy. In animal and preclinical studies, various forms of cardiovascular drug therapy seem to have a positive effect on vascular calcification. In particular, calcium channel blockers and inhibitors of the renin-angiotensin-aldosteron system slowed down arterial calcification in experimental animals. In humans, the results of trials with these drugs are far less pronounced and often contradictory. There is limited evidence that the development of new atherosclerotic lesions may be retarded in patients with coronary artery disease, but existing lesions can hardly be influenced. Although statin therapy has a proven role in the prevention and treatment of cardiovascular morbidity and mortality, it is associated with both regression and acceleration of the vascular calcification process. Recently, nutritional supplements have been recognized as a potential tool to reduce calcification. This is particularly true for vitamin K, which acts as an inhibitor of vascular calcification. In addition to vitamin K, other dietary supplements may also modulate vascular function. In this narrative review, we discuss the current state of knowledge regarding the pharmacological and nutritional possibilities to prevent the development and progression of vascular calcification.

Osteoporosis and vascular calcification: A shared scenario

Osteoporosis is a systemic skeletal disease, characterised by low bone mass and deterioration in the micro-architecture of bone tissue, which causes increased bone fragility and consequently greater susceptibility to fractures. It is the most frequent metabolic bone disease in our population, and fractures resulting from osteoporosis are becoming more common. Furthermore, vascular calcification is a recognised risk factor of cardiovascular morbidity and mortality that historically has been considered a passive and degenerative process. However, it is currently recognised as an active process, which has histopathological characteristics, mineral composition and initiation and development mechanisms characteristic of bone formation. Paradoxically, patients with osteoporosis frequently show vascular calcifications. Traditionally, they have been considered as independent processes related to age, although more recent epidemiological studies have shown that there is a close relationship between the loss of bone mass and vascular calcification, regardless of age. In fact, both conditions share risk factors and pathophysiological mechanisms. These include the relationship between proteins of bone origin, such as osteopontin and osteoprotegerin (OPG), with vascular pathology, and the intercellular protein system RANK/RANKL/OPG and the Wnt signalling pathway. The mechanisms linked in both pathologies should be considered in clinical decisions, given that treatments for osteoporosis could have unforeseen effects on vascular calcification, and vice versa. In short, a better understanding of the relationship between both entities can help in proposing strategies to reduce the increasing prevalence of vascular calcification and osteoporosis in the aging population.

The Problematic Use of Dietary Reference Intakes to Assess Magnesium Status and Clinical Importance

Determination of the public health concern about magnesium (Mg) in health and disease has been confounded by the lack of a practical measure of status. This has resulted in a lack of consistency in associating Mg deficiency with specific pathological conditions. Some attempts at associating Mg with a chronic disease have used the Dietary Reference Intakes (DRIs) as a status assessment measure. Use of current DRIs for Mg is problematic because recent evidence suggests that they should be updated and based on body weight. An evidence-based suggested Estimated Average Requirement (EAR) and Recommended Dietary Allowance (RDA) for a 70-kg individual is 175 and 250 mg/day, respectively. However, numerous dietary and physiological factors can affect the need for Mg and thus affect the use of the current or suggested new DRIs to assess Mg status. Calcium intakes above normal requirements can decrease Mg balance and exacerbate signs of Mg deficiency. Mg deficiency apparently occurs often in obesity because of increased need to counteract the inflammatory stress induced by adipose tissue dysfunction. Deficiency in anti-oxidant nutrients such as vitamin E and selenium can exacerbate a response to low dietary Mg indicated by increased oxidative stress which can lead to chronic disease. Dietary modifiers of Mg absorption and excretion affect balance and thus the need for Mg. Factors decreasing Mg balance include low dietary protein and non-fermentable fiber, while factors that can increase balance include fructose and fermentable fiber and fructose-containing oligosaccharides. Use of the DRIs to assess the Mg status of a population or group needs to consider their physiological characteristics and dietary habits and be aware that the DRIs may need updating. The DRIs only can be considered a component of a toolbox that presently includes serum Mg concentration and the daily urinary Mg excretion to assess the Mg status of an individual.

Association between Dietary Intake and Coronary Artery Calcification in Non-Dialysis Chronic Kidney Disease: The PROGREDIR Study

Coronary artery calcification (CAC) is a widespread condition in chronic kidney disease (CKD). Diet may play an important role in CAC, but this role is not clear. This study evaluated the association between macro-and micronutrient intakes and CAC in non-dialysis CKD patients. We analyzed the baseline data from 454 participants of the PROGREDIR study. Dietary intake was evaluated by a food frequency questionnaire. CAC was measured by computed tomography. After exclusion of participants with a coronary stent, 373 people remained for the analyses. The highest tertile of CAC was directly associated with the intake of phosphorus, calcium and magnesium. There was a higher intake of pantothenic acid and potassium in the second tertile. After adjustments for confounding variables, the intake of pantothenic acid, phosphorus, calcium and potassium remained associated with CAC in the generalized linear mixed models. In order to handle the collinearity between these nutrients, we used the LASSO (least absolute shrinkage and selection operator) regression to evaluate the nutrients associated with CAC variability. In this approach, the nutrients that most explained the variance of CAC were phosphorus, calcium and potassium. Prospective studies are needed to confirm these findings and assess the role of interventions regarding these micronutrients on CAC prevention and progression.

No difference in acute effects of supplementalv.dietary calcium on blood pressure and microvascular function in obese women challenged with a high-fat meal: a cross-over randomised study

Recent studies suggest that supplemental Ca (SC) increases the risk of cardiovascular events, whereas dietary Ca (DC) decreases the risk of cardiovascular events. Although frequently consumed with meals, it remains unclear whether Ca can mitigate or aggravate the deleterious effects of a high-fat meal on cardiovascular risk factors. This study aimed to evaluate the effects of SC or DC on blood pressure (BP) and microvascular function (MVF) in the postprandial period in obese women challenged with a high-fat meal. In this cross-over controlled trial, sixteen obese women aged 20–50 years were randomly assigned to receive three test meals (2908 kJ (695 kcal); 48 % fat): high DC (HDCM; 547 mg DC), high SC (HSCM; 500 mg SC–calcium carbonate) and low Ca (LCM; 42 mg DC). BP was continuously evaluated from 15 min before to 120 min after meals by digital photoplethysmography. Before and 120 min after meals, participants underwent evaluation of serum Ca and microvascular flow after postocclusive reactive hyperaemia (PORH) by laser speckle contrast imaging. Ionised serum Ca rose significantly only after HSCM. Systolic BP increased after the three meals, whereas diastolic BP increased after LCM and HDCM. Hyperaemia peak, hyperaemia amplitude and AUC evaluated after PORH decreased with LCM. After HDCM, there was a reduction in hyperaemia peak and hyperaemia amplitude, whereas HSCM decreased only hyperaemia peak. However, comparative analyses of the effects of three test meals on serum Ca, BP and MVF revealed no significant meal×time interaction. This study suggests that in obese women SC and DC do not interfere with the effects of a high-fat meal on BP and MVF.

Calcium Intake From Diet and Supplements and the Risk of Coronary Artery Calcification and its Progression Among Older Adults: 10-Year Follow-up of the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Recent randomized data suggest that calcium supplements may be associated with increased risk of cardiovascular disease (CVD) events. Using a longitudinal cohort study, we assessed the association between calcium intake, from both foods and supplements, and atherosclerosis, as measured by coronary artery calcification (CAC).

METHODS AND RESULTS

We studied 5448 adults free of clinically diagnosed CVD (52% female; aged 45-84 years) from the Multi-Ethnic Study of Atherosclerosis. Baseline total calcium intake was assessed from diet (using a food frequency questionnaire) and calcium supplements (by a medication inventory) and categorized into quintiles. Baseline CAC was measured by computed tomography, and CAC measurements were repeated in 2742 participants ≈10 years later. At baseline, mean calcium intakes across quintiles were 313.3, 540.3, 783.0, 1168.9, and 2157.4 mg/day. Women had higher calcium intakes than men. After adjustment for potential confounders, among 1567 participants without baseline CAC, the relative risk (RR) of developing incident CAC over 10 years, by quintile 1 to 5 of calcium intake, were 1 (reference), 0.95 (0.79-1.14), 1.02 (0.85-1.23), 0.86 (0.69-1.05), and 0.73 (0.57-0.93). After accounting for total calcium intake, calcium supplement use was associated with increased risk for incident CAC (RR=1.22 [1.07-1.39]). No relation was found between baseline calcium intake and 10-year changes in log-transformed CAC among those participants with baseline CAC >0.

CONCLUSIONS

High total calcium intake was associated with a decreased risk of incident atherosclerosis over long-term follow-up, particularly if achieved without supplement use. However, calcium supplement use may increase the risk for incident CAC.

Low Relative Lean Mass is Associated with Increased Likelihood of Abdominal Aortic Calcification in Community-Dwelling Older Australians

Age-related loss of skeletal muscle is associated with increased risk of functional limitation and cardiovascular (CV) mortality. In the elderly abdominal aortic calcification (AAC) can increase CV risk by altering aortic properties which may raise blood pressure and increase cardiac workload. This study investigated the association between low muscle mass and AAC in community-dwelling older Australians. Data for this cross-sectional analysis were drawn from a 2010 sub-study of the Melbourne Collaborative Cohort Study in the setting of community-dwelling older adults. Three hundred and twenty-seven participants [mean age = 71 ± 6 years; mean BMI = 28 ± 5 kg/m(2); females n = 199 (62 %)] had body composition determined by dual-energy x-ray absorptiometry (DXA) and AAC determined by radiography. Participants were stratified into tertiles of sex-specific BMI-normalised appendicular lean mass (ALM). Those in the lowest tertile were considered to have low relative muscle mass. Aortic calcification score (ACS) was determined visually as the extent of calcification on the aortic walls between L1 and L4 vertebrae (range: 0-24). Severe AAC was defined as ACS ≥ 6. Prevalence of any AAC was highest in participants with low relative muscle mass (74 %) compared to the middle (65 %) and upper (53 %) tertiles (p trend = 0.006). The lower ALM/BMI tertile had increased odds (Odds ratio = 2.3; 95 % confidence interval: 1.1-4.6; p = 0.021) of having any AAC; and having more severe AAC (2.2; 1.2-4.0; p = 0.009) independent of CV risk factors, serum calcium and physical activity. AAC is more prevalent and severe in community-dwelling older adults with low relative muscle mass. Maintaining muscle mass could form part of a broader primary prevention strategy in reducing AAC.

The association of calcium supplementation and incident cardiovascular events in the Multi-ethnic Study of Atherosclerosis (MESA)

BACKGROUND AND AIMS

Many US adults use calcium supplements to address inadequate dietary intake and improve bone health. However, recent reports have suggested that use of calcium supplements may elevate cardiovascular disease (CVD) risk. In this study, we examined associations between baseline calcium supplement use and incident myocardial infarction (MI) (n = 208 events) and CVD events (n = 641 events) over 10.3 years in men and women from the Multi-Ethnic Study of Atherosclerosis (MESA) cohort (n = 6236), with dietary calcium intake at baseline also examined as a supplementary objective.

METHODS AND RESULTS

Using Cox proportional hazards models, no compelling associations between calcium intake from supplements or diet and incident CVD events were observed upon multivariate adjustment for potential confounders. An association with lower MI risk was observed comparing those with low levels of calcium supplement use (1-499 mg) to those using no calcium supplements (hazard ratio 0.69, 95% CI 0.48, 0.98, p = 0.039). Relationships were homogeneous by gender, race/ethnicity, or chronic kidney disease. Results were also similar when the analysis was limited to postmenopausal women only.

CONCLUSION

Analysis of incident MI and CVD events in the MESA cohort does not support a substantial association of calcium supplement use with negative cardiovascular outcomes.

The Impact of Different Amounts of Calcium Intake on Bone Mass and Arterial Calcification in Ovariectomized Rats

Reduced estrogen secretion and low calcium (Ca) intake are risk factors for bone loss and arterial calcification in female rodents. To evaluate the effects of Ca intake at different amounts on bone mass changes and arterial calcification, 8-wk-old female Wistar rats were randomly placed in ovariectomized (OVX) control and OVX with vitamin D3 plus nicotine (VDN) treatment groups. The OVX with VDN rats were then divided into six groups to receive different amounts of Ca in their diets: 0.01%, 0.1%, 0.3%, 0.6%, 1.2%, or 2.4% Ca. After 8 wk of administration, low Ca intake groups with 0.01% and 0.1% Ca diets had significantly reduced bone mineral density (BMD) and bone mechanical properties as compared with those of the other groups, whereas high Ca intake groups with 1.2% and 2.4% Ca diets showed no differences as compared with the 0.6% Ca intake group. For both the 0.01% and 2.4% Ca intake groups, Ca levels in their thoracic arteries were significantly higher as compared with those of the 0.6% Ca diet group, and that was highly correlated with serum PTH levels. An increase in relative BMP-2 mRNA expression in the arterial tissues of the 0.01% and 2.4% Ca diet groups was also observed. These results suggested that extremely low Ca intake during periods of estrogen deficiency may be a possible risk for the complications of reduced BMD and arterial calcification and that extremely high Ca intake may promote arterial calcification with no changes in BMD.

Calcium intake and mortality from all causes, cancer, and cardiovascular disease: the Cancer Prevention Study II Nutrition Cohort

BACKGROUND

Calcium intake may be important for bone health, but its effects on other outcomes, including cardiovascular disease (CVD) and cancer, remain unclear. Recent reports of adverse cardiovascular effects of supplemental calcium have raised concerns.

OBJECTIVE

We investigated associations of supplemental, dietary, and total calcium intakes with all-cause, CVD-specific, and cancer-specific mortality in a large, prospective cohort.

DESIGN

A total of 132,823 participants in the Cancer Prevention Study II Nutrition Cohort, who were followed from baseline (1992 or 1993) through 2012 for mortality outcomes, were included in the analysis. Dietary and supplemental calcium information was first collected at baseline and updated in 1999 and 2003. Multivariable-adjusted Cox proportional hazards models with cumulative updating of exposures were used to calculate RRs and 95% CIs for associations between calcium intake and mortality.

RESULTS

During a mean follow-up of 17.5 y, 43,186 deaths occurred. For men, supplemental calcium intake was overall not associated with mortality outcomes (P-trend > 0.05 for all), but men who were taking ≥1000 mg supplemental calcium/d had a higher risk of all-cause mortality (RR: 1.17; 95% CI: 1.03, 1.33), which was primarily attributed to borderline statistically significant higher risk of CVD-specific mortality (RR: 1.22; 95% CI: 0.99, 1.51). For women, supplemental calcium was inversely associated with mortality from all causes [RR (95% CI): 0.90 (0.87, 0.94), 0.84 (0.80, 0.88), and 0.93 (0.87, 0.99) for intakes of 0.1 to <500, 500 to <1000, and ≥1000 mg/d, respectively; P-trend < 0.01]. Total calcium intake was inversely associated with mortality in women (P-trend < 0.01) but not in men; dietary calcium was not associated with all-cause mortality in either sex.

CONCLUSIONS

In this cohort, associations of calcium intake and mortality varied by sex. For women, total and supplemental calcium intakes are associated with lower mortality, whereas for men, supplemental calcium intake ≥1000 mg/d may be associated with higher all-cause and CVD-specific mortality.

Effects of supplementation with a calcium-rich marine-derived multi-mineral supplement and short-chain fructo-oligosaccharides on serum lipids in postmenopausal women

Recent literature suggests that Ca supplements have adverse effects on cardiovascular health. The effects of a Ca-rich supplement administered alone or in combination with short-chain fructo-oligosaccharides (scFOS) on serum lipids in postmenopausal women were examined using secondary data from a 24-month double-blind randomised controlled study. A total of 300 postmenopausal women were randomly assigned to daily supplements of 800 mg of Ca (2·4 g Aquamin) (Ca), 800 mg of Ca with 3 g of scFOS (CaFOS) or control (maltodextrin) (MD). A full lipid profile, body composition, blood pressure and a range of cytokines were measured at baseline and after 24 months. Intention-to-treat ANCOVA assessed treatment effects between the groups. A significant time-by-treatment effect was observed for LDL and total cholesterol for the Ca and CaFOS groups, with both groups having lower LDL and total cholesterol concentrations compared with MD after 24 months. The control group had mean (5·2 mmol/l) total cholesterol concentrations above the normal range (≤5 mmol/l) at 24 months, whereas values remained within the normal range in the treatment groups. There was no significant treatment effect on HDL-cholesterol, TAG, body composition, blood pressure or cytokine concentrations at 24 months, with the exception of IL-4, where there was a significant increase in the CaFOS group compared with the placebo. This study demonstrates a lipid-lowering effect of both the Ca-rich supplement alone and the supplement with scFOS. At the 4-year follow-up, there was no significant difference between the groups for reported diagnosed cardiovascular conditions.

Effect of High-Calcium Diet on Coronary Artery Disease in Ossabaw Miniature Swine With Metabolic Syndrome

Background

Calcium is a shortfall essential nutrient that has been a mainstay of osteoporosis management. Recent and limited findings have prompted concern about the contribution of calcium supplementation to cardiovascular risk. A proposed mechanism is through the acceleration of coronary artery calcification. Determining causality between calcium intake and coronary artery calcification has been hindered by a lack of sensitive methodology to monitor early vascular calcium accumulation. The primary study aim was to assess the impact of high calcium intake on coronary artery calcification using innovative calcium tracer kinetic modeling in Ossabaw swine with diet-induced metabolic syndrome. Secondary end points (in vitro wire myography, histopathology, intravascular ultrasound) assessed coronary disease.

Methods and Results

Pigs (n =24; aged ≈15 months) were fed an atherogenic diet with adequate calcium (0.33% by weight) or high calcium (1.90% from calcium carbonate or dairy) for 6 months. Following 5 months of feeding, all pigs were dosed intravenously with ⁴¹Ca, a rare isotope that can be measured in serum and tissues at a sensitivity of 10⁻¹⁸ mol/L by accelerator mass spectrometry. Kinetic modeling evaluated early coronary artery calcification using ⁴¹Ca values measured in serial blood samples (collected over 27 days) and coronary artery samples obtained at sacrifice. Serum disappearance of ⁴¹Ca and total coronary artery ⁴¹Ca accumulation did not differ among groups. Secondary end points demonstrated no treatment differences in coronary artery disease or function.

Conclusion

There was no detectable effect of high calcium diets (from dairy or calcium carbonate) on coronary artery calcium deposition in metabolic syndrome swine.

Lack of association of oral calcium supplementation with coronary artery calcification in rheumatoid arthritis

OBJECTIVE

To investigate the association between oral calcium supplementation and coronary artery calcification among rheumatoid arthritis (RA) patients without known cardiovascular disease (CVD).

METHODS

This study was conducted as a nested, prospective cohort study of RA patients without known CVD. The daily supplemental calcium dose was ascertained from each patients' list of prescription and over-the-counter medications at baseline and at visit 2 (median 20 months postbaseline). The coronary artery calcium (CAC) score, a measure of coronary atherosclerosis, was assessed by cardiac multidetector row computed tomography at baseline and at visit 3 (median 39 months postbaseline). The association between calcium supplementation and CAC was explored.

RESULTS

Among the 145 RA patients studied, 42 (28%) were taking ≥1,000 mg/day of supplemental calcium at baseline. A CAC score of >100 units was seen in 44 patients (30%) at baseline and 50 patients (34%) at followup. Baseline CAC scores of >100 units were significantly less frequent in patients receiving the higher dosage (≥1,000 mg/day) of supplemental calcium than in those receiving the lower dosage (<1,000 mg/day) (odds ratio [OR] 0.28, 95% confidence interval [95% CI] 0.11-0.74); this association remained significant after adjustment for relevant confounders (adjusted OR 0.30, 95% CI 0.09-0.93). Similarly, at the third study visit, CAC scores of >100 units were less frequent in the higher supplemental calcium dose group compared to the lower dose group (OR 0.41, 95% CI 0.18-0.95); however, after adjustment for relevant confounders, the statistical significance of this association was lost (adjusted OR 0.39, 95% CI 0.14-1.12). No effect of sex heterogeneity was seen in the association of calcium supplementation with coronary artery calcification, and no change in the CAC score over time was observed.

CONCLUSION

Higher levels of oral calcium supplementation were not associated with an increased risk of coronary atherosclerosis, as measured by the CAC score, in this RA cohort.

Dietary calcium and Framingham Risk Score in vitamin D deficient male (KNHANES 2009-2011)

PURPOSE

The association between excess calcium intake and cardiovascular mortality has already been reported. In the present study, we investigated the relation between dietary calcium intake and Framingham Risk Score (FRS) according to serum 25-hydroxyvitamin D [25(OH)D] status.

MATERIALS AND METHODS

A total of 7809 subjects (3452 males and 4357 female) aged over 40 years were selected for this cross-sectional study from data obtained from the Korea National Health and Nutrition Examination Survey (2008-2011). Daily dietary calcium intake was categorized into <300, 300-600, 600-900, 900-1200, and >1200 mg/day and serum 25(OH)D concentration classified into <50, 50-75, >75 mmol/L. The FRS was compared by the daily dietary calcium intake categories according to 25(OH)D concentration after adjustment with relevant variables in both genders.

RESULTS

Higher FRS was observed in males with both <300 mg and >1200 mg of dietary calcium intake and females with <300 mg of dietary calcium intake without adjustment. The significantly higher FRS remained in the <300 mg and >1200 mg of dietary calcium intake groups in both genders after adjustments for relevant variables. FRS was significantly higher in the group with >1200 mg of dietary calcium intake and serum 25(OH)D <50 nmol/L, which was the male only vitamin D deficient group.

CONCLUSION

Very low (<300 mg/day) and excess (>1200 mg/day) dietary calcium intake were related with higher FRS in both genders. In particular, higher FRS was observed in the excess (>1200 mg/day) dietary calcium intake male group under vitamin D deficiency (<50 nmol/L).

A review of the effect of diet on cardiovascular calcification

Cardiovascular (CV) calcification is known as sub-clinical atherosclerosis and is recognised as a predictor of CV events and mortality. As yet there is no treatment for CV calcification and conventional CV risk factors are not consistently correlated, leaving clinicians uncertain as to optimum management for these patients. For this reason, a review of studies investigating diet and serum levels of macro- and micronutrients was carried out. Although there were few human studies of macronutrients, nevertheless transfats and simple sugars should be avoided, while long chain ω-3 fats from oily fish may be protective. Among the micronutrients, an intake of 800 μg/day calcium was beneficial in those without renal disease or hyperparathyroidism, while inorganic phosphorus from food preservatives and colas may induce calcification. A high intake of magnesium (≥380 mg/day) and phylloquinone (500 μg/day) proved protective, as did a serum 25(OH)D concentration of ≥75 nmol/L. Although oxidative damage appears to be a cause of CV calcification, the antioxidant vitamins proved to be largely ineffective, while supplementation of α-tocopherol may induce calcification. Nevertheless other antioxidant compounds (epigallocatechin gallate from green tea and resveratrol from red wine) were protective. Finally, a homocysteine concentration >12 µmol/L was predictive of CV calcification, although a plasma folate concentration of >39.4 nmol/L could both lower homocysteine and protect against calcification. In terms of a dietary programme, these recommendations indicate avoiding sugar and the transfats and preservatives found in processed foods and drinks and adopting a diet high in oily fish and vegetables. The micronutrients magnesium and vitamin K may be worthy of further investigation as a treatment option for CV calcification.

Calcium and bone health--goodbye, calcium supplements?

This review assesses (1) the potential role of calcium supplements in the prevention and treatment of osteoporosis and osteoporotic fractures, and (2) the safety of calcium supplements with respect to cardiovascular health as well. With regard to (1), a total calcium intake of < 800 mg/day is associated with increased loss of bone mineral density in peri- and postmenopausal women with an increase in fracture risk. Hereby, the effect of calcium supplements on fracture prevention is dependent primary on baseline calcium intake. The strongest protective effect has been reported in individuals with a calcium intake < 700 mg/day and in high-risk groups. A calcium intake of about 1000-1200 mg/day seems to be sufficient for general fracture prevention. With regard to (2), an analysis of the data based on the Hill criteria does not demonstrate convincing evidence that calcium supplements increase cardiovascular risk. In the long term, total calcium intake of 2500 mg/day (from food and supplements) continues to be classified as safe. This value should not be exceeded for an extended period of time.

Fasting serum CGRP levels are related to calcium concentrations, but cannot be elevated by short-term calcium/vitamin D supplementation

Calcitonin gene-related peptide (CGRP) is an important cardioprotective neuropeptide. Few studies have shown that calcium supplementation may increase CGRP levels transiently. However, the relationship between CGRP and calcium is poorly known. This study was to explore the correlation between serum calcium and CGRP in coronary artery disease (CAD), and observe whether short-term calcium/vitamin D supplementation would increase fasting serum CGRP. A randomized, placebo-controlled and double-blind clinical trial, and a supplementary study for further analysis of the correlations were conducted. The results showed that the correlation between serum calcium and CGRP was positive in CAD without myocardial infarction (MI) (r = 0.487, P = 0.029), but negative in acute and healing MI (r = -0.382, P = 0.003). Moreover, we found a positive correlation between lg (amino-terminal pro-B-type natriuretic peptide, NT-proBNP) and CGRP (r = 0.312, P = 0.027), but a negative correlation between lg (NT-proBNP) and serum calcium (r = -0.316, P = 0.025) in acute and healing MI. As to the clinical trial, participants subjected to CAD but without evolving or acute MI, together with blood calcium ≤ 2.4 mmol/L, were randomized into three groups. Among the groups of placebo, caltrate (600 mg elemental calcium; 125 IU vitamin D3, per tablet) 1 tablet/d and caltrate 2 tablets/d, there were no significant differences in baseline characteristics. After short-term (5 days) treatments, the results indicated that the effect of grouping was not statistically significant (P = 0.915). In conclusion, the correlations between serum calcium and CGRP in different types of CAD are inconsistent, and the main reason may be associated with elevated natriuretic peptides after acute MI. Further, our study shows that short-term calcium/vitamin D supplementation cannot significantly increase fasting serum CGRP levels.

The cardiovascular safety aspects of calcium supplementations: where does the truth lie? A personal perspective

Clinical guidelines may change with time, as more information from topline studies emerges. Calcium plus vitamin D supplementation became routine decades ago, especially in the older population, based on the assumption that it may promote bone health and prevent fractures, and perhaps induce additional favorable health outcomes. During the past years, an ongoing debate defies this paradigm, mainly because of a potential cardiovascular risk on the one hand, and uncertainty in regard to the extent of the beneficial bone effects on the other hand. The following article summarizes the main recent developments, trying to put some order into the controversial information and opinions which have been published in the medical literature. We conclude that the best current evidence supports a primary strategy of obtaining recommended intakes of calcium and vitamin D from dietary sources. But, since most western diets are inadequate in that regard, and since there is no clear evidence of harm from modest supplementation (up to 1000 mg of elemental calcium and 400 IU of vitamin D3), supplementation is appropriate when dietary intake is inadequate.

Calcium revisited: part II calcium supplements and their effects

Calcium supplements were tested in pregnancy and lactation, in childhood and adolescence, in pre- and postmenopausal women and in elderly persons with various effects on bone density and fracture incidence. They must be properly chosen and adequately used. In this case, the reported minor negative side-effects do not restrict their use. All these aspects are reviewed here.

Cross-sectional analysis of calcium intake for associations with vascular calcification and mortality in individuals with type 2 diabetes from the Diabetes Heart Study

BACKGROUND

The use of calcium supplements to prevent declines in bone mineral density and fractures is widespread in the United States, and thus reports of elevated cardiovascular disease (CVD) risk in users of calcium supplements are a major public health concern. Any elevation in CVD risk with calcium supplement use would be of particular concern in individuals with type 2 diabetes (T2D) because of increased risks of CVD and fractures observed in this population.

OBJECTIVE

In this study, we examined associations between calcium intake from diet and supplements and measures of subclinical CVD (calcified plaque in the coronary artery, carotid artery, and abdominal aorta) and mortality in individuals affected by T2D.

DESIGN

We performed a cross-sectional analysis in individuals affected by T2D from the family-based Diabetes Heart Study (n = 720).

RESULTS

We observed no significant associations of calcium from diet or supplements with any of our measures of calcified plaque, and no greater mortality risk was observed with increased calcium intake. Instead, calcium supplement use was modestly associated with reduced all-cause mortality in women (HR: 0.62; 95% CI: 0.42, 0.92; P = 0.017).

CONCLUSION

Our results do not support a substantial association between calcium intake from diet or supplements and CVD risk in individuals with T2D.

Controversy regarding the association of high calcium intake and increased risk for cardiovascular disease

Calcium intake has been shown to be associated with beneficial effects regarding hypertension, coronary heart disease (CHD), vascular disease, and stroke by several prospective cohort studies. However, recent studies have questioned the beneficial cardiovascular effects of calcium intake and instead have shown that high calcium intake is associated with an increased risk for CHD and stroke. These findings have created controversy and concern among physicians, because calcium is consumed by a large number of older men and women to prevent osteoporosis and bone fractures. Based on the methods of patient self-reporting of calcium intake and cardiovascular events, the conclusions drawn from the studies may not be entirely valid. Therefore, until more confirmatory data are available, physicians should not be dissuaded from prescribing calcium supplements to their patients. The best candidates are patients with low calcium intake, but their calcium supplementation should not exceed the recommended 1200 mg/d to 1500 mg/d.

Dietary intake of calcium and phosphorus and serum concentration in relation to the risk of coronary artery calcification in asymptomatic adults

OBJECTIVE

The current data regarding the association between calcium and phosphorus and cardiovascular disease are lacking. The aim of this study was to explore whether dietary calcium and phosphorus intake and their serum levels are associated with the prevalence of coronary artery calcification (CAC) using cardiac computed tomography in asymptomatic participants without a history of chronic kidney disease or cardiovascular disease.

APPROACH AND RESULTS

A cross-sectional study was performed in 23 652 Korean participants (40.8±7.3 years, male 83.5%) without chronic kidney disease (estimated glomerular filtration rate≥60 mL/min per 1.73 m(2)) or clinically overt cardiovascular disease, who underwent cardiac computed tomographic estimation of CAC scores as part of a general health checkup in addition to completing a self-administered food frequency questionnaire. We assessed the relationship of dietary calcium and phosphorus intake and serum levels with CAC scores using both multivariate-adjusted Tobit models and multinomial logistic regression models. Neither dietary calcium nor phosphorus intake was consistently associated with CAC scores. However, the serum calcium, phosphorus, and calcium-phosphorus product levels were significantly associated with the CAC score ratios. In multivariable-adjusted models, the CAC score ratios (95% confidence intervals) comparing the highest quartiles of serum calcium, phosphorus, and calcium-phosphorus product levels to the lowest quartiles were 1.89 (1.36-2.64), 3.33 (2.55-4.35), and 3.98 (3.00-5.28), respectively (P for trend <0.001).

CONCLUSIONS

Elevated serum levels of calcium, phosphorus, and calcium-phosphorus product, but not dietary consumption, are associated with increased CAC scores. Our findings should be explored in further research.

Calcium supplementation: is protecting against osteoporosis counter to protecting against cardiovascular disease?

Calcium is the dominant mineral in bone and is a shortfall nutrient in the diet. For those consuming inadequate dietary calcium, calcium supplements have been a standard strategy for prevention of osteoporosis. Recently, calcium supplementation has been linked to both increased and decreased cardiovascular disease risk creating considerable uncertainty. Moreover, recent reports have shed uncertainty over the effectiveness of calcium supplements to reduce risk of fracture. The evidence for calcium supplementation effects to both reduce risk of fracture and increase coronary heart disease and mortality are reviewed. Although the importance of good calcium nutrition is well known, determining the advantage of calcium supplementation to either bone or heart health has been hampered by poor subject compliance and study design flaws. At present, the current Recommended Dietary Allowances for calcium still appear to be a good target with potential risks for chronic disease if intakes fall too short or greatly exceed these recommendations.

Effects of a typical acute oral calcium load on arterial properties and endothelial function in healthy subjects

BACKGROUND/OBJECTIVES

Often recommended, calcium supplements have been incriminated as increasing the risk of cardiovascular events, whereas dietary calcium has generally been exonerated. As a first step to address the vascular safety of such dietary measures at the clinical nutritionist toolbox, we sought to determine and compare the acute effects of a typical oral calcium load, provided either as a supplement or as food, on vascular parameters assessed noninvasively in healthy subjects.

SUBJECTS/METHODS

In this acute, cross-over, random-order intervention, 11 young and healthy vitamin D-sufficient volunteers (8 women/3 men, 33±6.1 years, body mass index 22.6±2.3 kg/m(2)), ingested 600 mg of calcium twice, once as calcium citrate and the other time from dairy products. Biochemical, vascular and hemodynamic parameters, before and 2 h after each challenge, were compared. Arterial stiffness was studied by measuring pulse wave velocity, augmentation index and large (C1) and small (C2) arterial compliance. Endothelial function was assessed by flow-mediated dilation (FMD).

RESULTS

Despite effective calcium loading accompanied by a significant 60% parathyroid hormone level reduction on both occasions, there were no clinically significant changes in the vascular parameters neither in comparison with baseline, nor between the studies. A decrease in heart rate with no change in cardiac output was noticed after the supplement.

CONCLUSIONS

An effective calcium load has no clinically significant untoward effect on the vascular properties of young healthy subjects, regardless of its source. Additional studies should determine whether this holds true for chronic calcium supplementation, particularly in subjects with a priori vascular impairment.

Milk, dairy products, and their functional effects in humans: a narrative review of recent evidence

Milk is a widely consumed beverage that is essential to the diet of several millions of people worldwide because it provides important macro- and micronutrients. Milk is recognized as being useful during childhood and adolescence because of its composition; however, its relatively high saturated fat proportion raises issues of potential detrimental effects, namely on the cardiovascular system. This review evaluates the most recent literature on dairy and human health, framed within epidemiologic, experimental, and biochemical evidence. As an example, the effects of milk (notably skimmed milk) on body weight appear to be well documented, and the conclusions of the vast majority of published studies indicate that dairy consumption does not increase cardiovascular risk or the incidence of some cancers. Even though the available evidence is not conclusive, some studies suggest that milk and its derivatives might actually be beneficial to some population segments. Although future studies will help elucidate the role of milk and dairy products in human health, their use within a balanced diet should be considered in the absence of clear contraindications.

The effects of 3 years of calcium supplementation on common carotid artery intimal medial thickness and carotid atherosclerosis in older women: an ancillary study of the CAIFOS randomized controlled trial

Calcium is an essential nutrient for skeletal health; however, it has been suggested that supplemental calcium may be associated with adverse cardiovascular effects, raising widespread concern about their use. One suggested mechanism is via increasing carotid atherosclerosis, however few randomized controlled trials (RCT) of calcium supplements have assessed these mechanisms. The calcium intake fracture outcome study (CAIFOS) was a 5-year RCT (1998 to 2003) of 1.2 g of elemental calcium in the form of calcium carbonate in 1460 elderly women. An ancillary study of 1103 women assessed common carotid artery intimal medial thickness (CCA-IMT) and carotid atherosclerosis at year 3 (2001). The effects of supplementation were studied in intention-to-treat (ITT) and per-protocol (PP) analyses before and after adjustment for baseline cardiovascular risk factors. The mean age of participants at baseline was 75.2 ± 2.7 years. In ITT analyses, women randomized to calcium supplementation had no difference in multivariable-adjusted mean CCA-IMT (calcium 0.778 ± 0.006 mm, placebo 0.783 ± 0.006 mm, p = 0.491) and maximum CCA-IMT (calcium 0.921 ± 0.007 mm, placebo 0.929 ± 0.006 mm, p = 0.404). Women randomized to calcium did not have increased carotid atherosclerosis (calcium 47.2%, placebo 52.7%, p = 0.066). However, in women taking at least 80% of the supplements, a significant reduction in carotid atherosclerosis was observed in unadjusted but not in multivariate-adjusted models (p = 0.033 and p = 0.064, respectively). Participants in the highest tertile of total calcium (diet and supplements) had reduced carotid atherosclerosis in unadjusted and multivariable-adjusted analyses compared with participants in the lowest tertile (odds ratio [OR] = 0.67 [95% confidence interval (CI) 0.50-0.90], p = 0.008, and OR = 0.70 [95% CI 0.51-0.96], p = 0.028, respectively). In conclusion, these findings do not support the hypothesis that calcium supplementation increases carotid artery intimal medial thickness or carotid atherosclerosis, and high calcium intake may reduce this surrogate cardiovascular risk factor.

The structural consequences of calcium crystal deposition

Calcium pyrophosphate dihydrate and basic calcium phosphate (BCP) crystals are the most common calcium-containing crystals associated with rheumatic disease. Clinical manifestations of calcium crystal deposition include acute or chronic inflammatory and degenerative arthritides and certain forms of periarthritis. The intra-articular presence of BCP crystals correlates with the degree of radiographic degeneration. Calcium crystal deposition contributes directly to joint degeneration. Vascular calcification is caused by the deposition of calcium hydroxyapatite crystals in the arterial intima. These deposits may contribute to local inflammation and promote further calcification, thus aggravating the atherosclerotic process. Calcium crystal deposition results in substantial structural consequence in humans.

Vascular calcification

PURPOSE OF REVIEW

This review presents new evidence related to molecular mechanisms involved in the process of cardiovascular calcification, as well as to discuss new biomarkers and novel therapeutic strategies related to vascular calcification in chronic kidney disease (CKD) patients.

RECENT FINDINGS

microRNAs have emerged as potential players in the genesis of osteo-chondrogenic transformation, depending on the stimulus and the localization of vascular calcification. The disturbances of the fibroblast growth factor-23 (FGF23)/alpha-Klotho (Klotho) axis observed in CKD appear to play an important role in CKD-associated vascular calcification. Numerous studies have identified circulating biomarkers potentially responsible for vascular calcification and have evaluated their link with this process. The respective role of these biomarkers is not yet elucidated. Beyond phosphate binders, modulation of calcium-sensing receptor and vitamin K supplementation come into sight as new potential strategies to prevent cardiovascular calcification.

CONCLUSION

A better understanding of the molecular mechanisms which are responsible for cardiovascular calcification have led to a better detection and more adequate follow-up of this pathologic process, as well as the identification of novel therapeutic targets. Whether these new insights will lead to improved care and better survival of CKD patients with cardiovascular calcification remains to be demonstrated.

Anti-osteoporotic drugs and vascular calcification: the bidirectional calcium traffic

During the last years, numerous epidemiological studies have demonstrated a direct relationship between vascular calcification and low bone mineral density. This observation is in line with experimental data demonstrating the osteogenic characteristics of calcified arteries. Various common risk factors have been suggested to link vascular calcification and bone loss, including aging, estrogen deficiency, vitamin D and K deficiency, diabetes mellitus, renal failure, smoking, chronic inflammation and oxidative stress. Although the underlying pathogenetic mechanisms are not yet clear, current research is focusing on anti-osteoporotic agents that could potentially affect the deposition of calcium in the arterial wall and thus provide an additional therapeutic strategy in elderly osteoporotic women prone to calcific cardiovascular disease.

Clinical practice. Calcium supplements and fracture prevention

This Journal feature begins with a case vignette highlighting a common clinical problem. Evidence supporting various strategies is then presented, followed by a review of formal guidelines, when they exist. The article ends with the author’s clinical recommendations. A 62-year-old healthy woman presents for routine care. She has no history of fracture, but she is worried about osteoporosis because her mother had a hip fracture at 72 years of age. She exercises regularly and has taken over-the-counter calcium carbonate at a dose of 1000 mg three times a day since her menopause at 54 years of age. This regimen provides 1200 mg of elemental calcium per day. She eats a healthy diet with multiple servings of fruits and vegetables and consumes one 8-oz serving of low-fat yogurt and one glass of low-fat milk almost every day. She recently heard that calcium supplements could increase her risk of cardiovascular disease and wants your opinion about whether or not she should receive them. What would you advise?

Risk of high dietary calcium for arterial calcification in older adults

Concern has recently arisen about the potential adverse effects of excessive calcium intakes, i.e., calcium loading from supplements, on arterial calcification and risks of cardiovascular diseases (CVD) in older adults. Published reports that high calcium intakes in free-living adults have relatively little or no beneficial impact on bone mineral density (BMD) and fracture rates suggest that current recommendations of calcium for adults may be set too high. Because even healthy kidneys have limited capability of eliminating excessive calcium in the diet, the likelihood of soft-tissue calcification may increase in older adults who take calcium supplements, particularly in those with age or disease-related reduction in renal function. The maintenance of BMD and bone health continues to be an important goal of adequate dietary calcium consumption, but eliminating potential risks of CVDs from excessive calcium intakes needs to be factored into policy recommendations for calcium by adults.

Calcium and vitamin D supplementation and loss of bone mineral density in women undergoing breast cancer therapy

An unintended consequence of breast cancer therapies is an increased risk of osteoporosis due to accelerated bone loss. We conducted a systematic review of calcium and/or vitamin D (Ca±D) supplementation trials for maintaining bone mineral density (BMD) in women with breast cancer using the "before-after" data from the Ca±D supplemented comparison group of trials evaluating the effect of drugs such as bisphosphonates on BMD. Whether Ca±D supplements increase BMD in women undergoing breast cancer therapy has never been tested against an unsupplemented control group. However, results from 16 trials indicate that the Ca±D doses tested (500-1500mg calcium; 200-1000IU vitamin D) were inadequate to prevent BMD loss in these women. Cardiovascular disease is the main cause of mortality in women with breast cancer. Because calcium supplements may increase cardiovascular disease risk, future trials should evaluate the safety and efficacy of Ca±D supplementation in women undergoing breast cancer therapy.

Screening for subclinical atherosclerosis by noninvasive methods in asymptomatic patients with risk factors

Atherosclerosis is a leading cause of cardiovascular death due to the increasing prevalence of the disease and the impact of risk factors such as diabetes, obesity or smoking. Sudden cardiac death is the primary consequence of coronary artery disease in 50% of men and 64% of women. Currently the only available strategy to reduce mortality in the at-risk population is primary prevention; the target population must receive screening for atherosclerosis. The value of screening for subclinical atherosclerosis is still relevant, it has become standard clinical practice with the emergence of new noninvasive techniques (radio frequency [RF] measurement of intima-media thickness [RFQIMT] and arterial stiffness [RFQAS], and flow-mediated vasodilatation [FMV]), which have been used by our team since 2007 and are based on detection marker integrators which reflect the deleterious effect of risk factors on arterial remodeling before the onset of clinical events. These techniques allow the study of values according to age and diagnosis of the pathological value, the thickness of the intima media (RFQIMT), the speed of the pulse wave (RFQAS), and the degree of endothelial dysfunction (FMV). This screening is justified in asymptomatic patients with cardiovascular risk factors (hypertension, diabetes, obesity, dyslipidemia, and tobacco smoking). Studies conducted by RF coupled with two-dimensional echo since 2007 have led to a more detailed analysis of the state of the arterial wall. The various examinations allow an assessment of the degree of subclinical atherosclerosis and its impact on arterial remodeling and endothelial function. The use of noninvasive imaging in screening and early detection of subclinical atherosclerosis is reliable and reproducible and allows us to assess the susceptibility of our patients with risk factors and ensures better monitoring of atherosclerosis, thus reducing the occurrence of cardiovascular events in the long term.