Evidence that calcium supplements reduce fracture risk is lacking

Risk of fracture according to temporal changes of low body weight changes in adults over 40 years: a nationwide population-based cohort study

BACKGROUND

Low body weight is associated with an increased risk of fractures. However, the effect of temporal changes in the low body weight status on the risk of fracture remains unknown. This study aimed to evaluate the relationships between temporal changes in low body weight status and the risk of fractures in adults over the age of 40 years.

METHODS

This study included data on adults over 40 years old who underwent two biannual consecutive general health examinations between January 1, 2007 and December 31, 2009 extracted from the National Health Insurance Database, a large nationwide population database. Fracture cases in this cohort were monitored from the time of the last health examination to the end of the designated follow-up period (from January 1, 2010 to December 31, 2018) or the participant's death. Fractures were defined as any fracture resulting in hospitalization or outpatient treatment claim after the date of general health screening. The study population was then separated into four groups based on the temporal changes in low body weight status as follows: low body weight to low body weight (L-to-L), low body weight to non-low body weight (L-to-N), non-low body weight to low body weight (N-to-L), and non-low body weight to non-low body weight (N-to-N). The hazard ratios (HRs) for new fractures, depending on weight changes over time, were calculated using Cox proportional hazard analysis.

RESULTS

Adults in the L-to-L, N-to-L, and L-to-N groups had a substantially increased risk of fractures after multivariate adjustment (HR, 1.165; 95% confidence interval [CI], 1.113-1.218; HR, 1.193; 95% CI, 1.131-1.259; and HR, 1.114; 95% CI, 1.050-1.183, respectively). Although the adjusted HR was greater in participants who changed into having a low body weight, followed by those with consistently low body weight, those with low body weight remained to have an elevated risk of fracture independent of weight fluctuation. Elderly men (aged over 65 years), high blood pressure, and chronic kidney disease were significantly associated with an increase in fractures (p < 0.05).

CONCLUSION

Individuals aged over 40 years with low body weight, even after regaining normal weight, had an increased risk of fracture. Moreover, having a low body weight after having a normal body weight increased the risk of fractures the most, followed by those with consistently low body weight.

Incidence of hip fracture in underweight individuals: a nationwide population-based cohort study in Korea

BACKGROUND

Hip fracture is a major public health problem worldwide and being underweight is a risk factor for fractures. Few studies have investigated the association between being underweight and hip fracture in the general population. The present study investigated the incidence of hip fracture in a large population cohort based on detailed information about the degree of underweight.

METHODS

A nationwide retrospective cohort study of adults ≥40 years of age included 962,533 subjects who were not overweight or obese in 2009. The incidence and risk of hip fracture occurring between 2010 and 2018 was assessed based on the degree of underweight. Based on body mass index (BMI), the study population was categorized into normal (18.50-22.99 kg/m² ), mild (17.00-18.49 kg/m² ), moderate (16.00-16.99 kg/m² ), and severe underweight (<16.00 kg/m² ) groups. Cox proportional hazards analyses were performed to calculate the hazard ratio (HR) for the hip fracture based on the degree of underweight in reference to the normal weight.

RESULTS

Compared with subjects who were normal weight, those who were classified as mild underweight (1.03/1000 person-years (PY) increase in incidence rate (IR); adjusted HR (aHR) 1.61; 95% confidence interval (CI) 1.48-1.76), moderate underweight (2.04/1000 PY increase in IR; aHR 1.85; 95% CI 1.65-2.08), or severe underweight (4.58/1000 PY increase in IR; aHR 2.33; 95% CI 2.03-2.66) were at significantly increased risk of hip fracture.

CONCLUSIONS

The severity of underweight was significantly associated with risk of hip fracture. The subdivision of underweight helps to estimate fracture risk more accurately.

Changes in Underweight Status and Risk of Hip Fracture: A Korean Nationwide Population-Based Cohort Study

Being underweight is associated with a high risk of hip fracture. However, the impact of change in underweight status on the risk of hip fracture is unknown. This study is performed to investigate the relationship between change in underweight status and risk of hip fracture. This study included 1,713,225 subjects aged ≥40 years who underwent two consecutive national health screenings between 2007 and 2009. We prospectively assessed the risk of hip fracture between 2010 and 2018 according to changes in underweight status. We divided the participants into four groups according to the change in underweight status: consistent non-underweight (non-underweight to non-underweight), became non-underweight (underweight to non-underweight), became underweight (non-underweight to underweight), and consistent underweight (underweight to underweight). Compared with the consistent non-underweight group, the became non-underweight (0.74/1000 person years (PY) increase in incidence rate (IR); adjusted hazard ratio (HR) 1.72; 95% confidence interval (CI) 1.42−2.07), became underweight (1.71/1000 PY increase in IR; adjusted HR 2.22; 95% CI 1.96−2.53), and consistent underweight (1.3/1000 PY increase in IR; adjusted HR 2.18; 95% CI 1.89−2.53) groups had a significantly increased risk of hip fracture (p < 0.001). Change in underweight status was significantly associated with a risk of hip fracture.

Dairy foods and bone health throughout the lifespan: a critical appraisal of the evidence

The consumption of high-Ca, high-protein dairy foods (i.e. milk, cheese, yogurt) is advocated for bone health across the lifespan to reduce the risk of low-trauma fractures. However, to date, the anti-fracture efficacy of dairy food consumption has not been demonstrated in randomised controlled trials but inferred from cross-sectional and prospective studies. The anti-fracture efficacy of dairy food consumption is plausible, but testing this requires a robust study design to ensure outcomes are suitably answering this important public health question. The evidence of skeletal benefits of dairy food consumption is equivocal, not because it may not be efficacious but because the study design and execution are often inadequate. The key issues are compliance with dietary intervention, dropouts, sample sizes and most importantly lack of deficiency before intervention. Without careful appraisal of the design and execution of available studies, precarious interpretations of outcomes may be made from these poorly designed or executed studies, without consideration of how study design may be improved. Dairy food interventions in children are further hampered by heterogeneity in growth: in particular sex and maturity-related differences in the magnitude, timing, location and surface-specific site of bone accrual. Outcomes of studies combining children of different sexes and maturity status may be masked or exaggerated by these differences in growth, so inaccurate conclusions are drawn from results. Until these critical issues in study design are considered in future dairy food interventions, the anti-fracture efficacy of dairy food consumption may remain unknown and continue to be based on conjecture.

STOPPFrail (Screening Tool of Older Persons Prescriptions in Frail adults with limited life expectancy): consensus validation

Objective

to validate STOPPFrail, a list of explicit criteria for potentially inappropriate medication (PIM) use in frail older adults with limited life expectancy.

Design

a Delphi consensus survey of an expert panel comprising academic geriatricians, clinical pharmacologists, palliative care physicians, old age psychiatrists, general practitioners and clinical pharmacists.

Setting

Ireland.

Subjects

seventeen panellists.

Methods

STOPPFrail criteria were initially created by the authors based on clinical experience and literature appraisal. Criteria were organised according to the physiological system; each criterion accompanied by an explanation. Using Delphi consensus methodology, panellists ranked their agreement with each criterion on a 5-point Likert scale and provided written feedback. Criteria with a median Likert response of 4/5 (agree/strongly agree) and a 25th centile of ≥4 were included in the final list.

Results

all panellists completed three Delphi rounds. Thirty criteria were proposed, 27 were accepted. The first two criteria suggest deprescribing medications without indication or where compliance is poor. The remaining 25 criteria include lipid-lowering therapies, alpha-blockers for hypertension, anti-platelets, neuroleptics, memantine, proton-pump inhibitors, H2-receptor antagonists, anti-spasmodic agents, theophylline, leukotriene antagonists, calcium supplements, bone anti-resorptive therapy, selective oestrogen receptor modulators, non-steroidal anti-inflammatories, corticosteroids, 5-alpha-reductase inhibitors, alpha-1-selective blockers, muscarinic antagonists, oral diabetic agents, ACE-inhibitors, angiotensin receptor blockers, systemic oestrogens, multivitamins, nutritional supplements and prophylactic antibiotics. Consensus could not be reached on the inclusion of acetylcholinesterase inhibitors. Full consensus was reached on the exclusion of anticoagulants and antidepressants from the list.

Conclusion

STOPPFrail comprises 27 criteria relating to medications that are potentially inappropriate in frail older patients with limited life expectancy. STOPPFrail may assist physicians in deprescribing medications in these patients.

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.

Impact and risk factors of post-stroke bone fracture

Bone fracture occurs in stroke patients at different times during the recovery phase, prolonging recovery time and increasing medical costs. In this review, we discuss the potential risk factors for post-stroke bone fracture and preventive methods. Most post-stroke bone fractures occur in the lower extremities, indicating fragile bones are a risk factor. Motor changes, including posture, mobility, and balance post-stroke contribute to bone loss and thus increase risk of bone fracture. Bone mineral density is a useful indicator for bone resorption, useful to identify patients at risk of post-stroke bone fracture. Calcium supplementation was previously regarded as a useful treatment during physical rehabilitation. However, recent data suggests calcium supplementation has a negative impact on atherosclerotic conditions. Vitamin D intake may prevent osteoporosis and fractures in patients with stroke. Although drugs such as teriparatide show some benefits in preventing osteoporosis, additional clinical trials are needed to determine the most effective conditions for post-stroke applications.

Calcium plus vitamin D supplementation and risk of fractures: an updated meta-analysis from the National Osteoporosis Foundation

The aim was to meta-analyze randomized controlled trials of calcium plus vitamin D supplementation and fracture prevention. Meta-analysis showed a significant 15 % reduced risk of total fractures (summary relative risk estimate [SRRE], 0.85; 95 % confidence interval [CI], 0.73-0.98) and a 30 % reduced risk of hip fractures (SRRE, 0.70; 95 % CI, 0.56-0.87).

INTRODUCTION

Calcium plus vitamin D supplementation has been widely recommended to prevent osteoporosis and subsequent fractures; however, considerable controversy exists regarding the association of such supplementation and fracture risk. The aim was to conduct a meta-analysis of randomized controlled trials [RCTs] of calcium plus vitamin D supplementation and fracture prevention in adults.

METHODS

A PubMed literature search was conducted for the period from July 1, 2011 through July 31, 2015. RCTs reporting the effect of calcium plus vitamin D supplementation on fracture incidence were selected from English-language studies. Qualitative and quantitative information was extracted; random-effects meta-analyses were conducted to generate summary relative risk estimates (SRREs) for total and hip fractures. Statistical heterogeneity was assessed using Cochran's Q test and the I (2) statistic, and potential for publication bias was assessed.

RESULTS

Of the citations retrieved, eight studies including 30,970 participants met criteria for inclusion in the primary analysis, reporting 195 hip fractures and 2231 total fractures. Meta-analysis of all studies showed that calcium plus vitamin D supplementation produced a statistically significant 15 % reduced risk of total fractures (SRRE, 0.85; 95 % confidence interval [CI], 0.73-0.98) and a 30 % reduced risk of hip fractures (SRRE, 0.70; 95 % CI, 0.56-0.87). Numerous sensitivity and subgroup analyses produced similar summary associations. A limitation is that this study utilized data from subgroup analysis of the Women's Health Initiative.

CONCLUSIONS

This meta-analysis of RCTs supports the use of calcium plus vitamin D supplements as an intervention for fracture risk reduction in both community-dwelling and institutionalized middle-aged to older adults.

Vertebral fracture prevalence among Greek healthy middle-aged postmenopausal women: association with demographics, anthropometric parameters, and bone mineral density

BACKGROUND CONTEXT

The prevalence of skeletal fractures shows a marked geographic variability; however, data regarding the Greek population remain limited.

PURPOSE

To evaluate the frequency of asymptomatic vertebral fractures (VFs), and potential risk factors, in a large sample of Greek postmenopausal women.

STUDY DESIGN

A cross-sectional study at the University Menopause Clinic.

PATIENT SAMPLE

Four hundred fifty-four postmenopausal women aged 35 to 80 years, with an average menopausal age of 9.2±7.1 years.

OUTCOME MEASURES

They included medical history, anthropometric and biochemical parameters, bone mineral density (BMD) at lumbar spine (LS) and femoral neck (FN), and LS lateral radiographs.

METHODS

Lumbar spine lateral radiographs were evaluated according to quantitative procedures, aiming to identify VFs. Anthropometric and biochemical parameters and values of BMD were compared according to the presence of VFs.

RESULTS

A total of 37 (8.15%) women had at least one VF. Lumbar spine and FN-osteoporosis was identified in up to 23.1% and 40.9% subjects with prevalent VFs, respectively. The prevalence of VFs was largely associated with age, with women aged 60 years or more presenting an up to fourfold risk compared with younger women. Moreover, the presence of VFs was associated with higher menopausal age, advanced age at menarche, a history of early menopause, and prolonged lactation. Lower LS-BMD and, especially, FN-BMD were negatively associated with VF prevalence (prevalent VF vs. no VF: LS-BMD, 0.89±0.16 g/cm(2) vs. 0.98±0.16 g/cm(2), p=.010; FN-BMD, 0.72±0.10 g/cm(2) vs. 0.81±0.12 g/cm(2), p=.008).

CONCLUSIONS

Asymptomatic VFs are common among Greek healthy middle-aged postmenopausal women. More than 50% subjects with prevalent VFs present with normal BMD or osteopenia. Age and bone density classification at the FN presented the strongest association with the prevalence of VFs.

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.

Supplementation with calcium and short-chain fructo-oligosaccharides affects markers of bone turnover but not bone mineral density in postmenopausal women

This 24-mo randomized, double-blind, controlled trial aimed to examine whether supplementation with a natural marine-derived multi-mineral supplement rich in calcium (Ca) taken alone and in conjunction with short-chain fructo-oligosaccharide (scFOSs) has a beneficial effect on bone mineral density (BMD) and bone turnover markers (BTMs) in postmenopausal women. A total of 300 non-osteoporotic postmenopausal women were randomly assigned to daily supplements of 800 mg of Ca, 800 mg of Ca with 3.6 g of scFOS (CaFOS), or 9 g of maltodextrin. BMD was measured before and after intervention along with BTMs, which were also measured at 12 mo. Intention-to-treat ANCOVA identified that the change in BMD in the Ca and CaFOS groups did not differ from that in the maltodextrin group. Secondary analysis of changes to BTMs over time identified a greater decline in osteocalcin and C-telopeptide of type I collagen (CTX) in the Ca group compared with the maltodextrin group at 12 mo. A greater decline in CTX was observed at 12 mo and a greater decline in osteocalcin was observed at 24 mo in the CaFOS group compared with the maltodextrin group. In exploratory subanalyses of each treatment group against the maltodextrin group, women classified with osteopenia and taking CaFOS had a smaller decline in total-body (P = 0.03) and spinal (P = 0.03) BMD compared with the maltodextrin group, although this effect was restricted to those with higher total-body and mean spinal BMD at baseline, respectively. Although the change in BMD observed did not differ between the groups, the greater decline in BTMs in the Ca and CaFOS groups compared with the maltodextrin group suggests a more favorable bone health profile after supplementation with Ca and CaFOS. Supplementation with CaFOS slowed the rate of total-body and spinal bone loss in postmenopausal women with osteopenia-an effect that warrants additional investigation. This trial was registered at www.controlled-trials.com as ISRCTN63118444.

Calcium balance and negative impact of calcium load in peritoneal dialysis patients

Like hemodialysis patients, peritoneal dialysis (PD) patients are facing an excessively increased burden of vascular and valvular calcification. According to some surveys, more than 80% of prevalent PD patients are complicated with vascular calcification, and more than one third have heart valve calcification. Dysregulated phosphate metabolism is well recognized to play an important role in inducing vascular calcification, but increasing evidence is suggesting that dysregulated calcium metabolism also promotes vascular calcification and might in fact be more potent than phosphate in inducing that calcification. Growing evidence from randomized controlled trials shows more progression of vascular calcification and higher mortality among chronic kidney disease (CKD) patients receiving calcium-based phosphate binders than among those receiving non-calcium-containing phosphate binders. Those results raise important safety concern about the use of high-dose calcium-based phosphate binders in the CKD population, including both non-dialysis and dialysis patients (especially anuric dialysis patients), who have markedly reduced urinary calcium excretion. To prevent calcium overload, this review recommends restricting the dose of calcium-based phosphate binders in CKD patients, especially those who are elderly, who have increased cardiovascular risk, who already have baseline vascular or valvular calcification, or who have low intact parathyroid hormone and adynamic bone disease.

The Auckland calcium study: 5-year post-trial follow-up

Five years after completion of a randomised placebo-controlled trial of calcium supplements, there was no effect of calcium on total fracture incidence, a significant reduction in vertebral and forearm fractures and, in a subset, no effect on bone density. There was no increased risk of cardiovascular events after discontinuation of calcium.

INTRODUCTION

The Auckland calcium study was a 5-year randomised controlled trial of 1 g/day calcium citrate in 1,471 postmenopausal women. Calcium did not reduce total, vertebral or forearm fracture incidence, increased hip fracture incidence and had beneficial effects on bone mineral density (BMD). A secondary analysis raised concerns about the cardiovascular safety of calcium. The purpose of this study was to determine whether the effects of calcium on fracture incidence, BMD and cardiovascular endpoints persisted after supplement discontinuation.

METHODS

Approximately 5-years post-trial, we collected information on the 1,408 participants alive at trial completion from the national databases of hospital admissions and deaths. We contacted 1,174 women by phone, and from these we obtained information on medical events and post-trial calcium use. We undertook BMD measurements at 10 years in a selected subset of 194 women who took study medication for 5 years in the original trial, and did not take bone-active medications post-trial.

RESULTS

Over the 10-year period, there was no effect on total fracture (HR 0.90, 95% CI 0.75-1.07) or hip fracture incidence (1.40, 0.89-2.21), but significant reductions in forearm (0.62, 0.43-0.89) and vertebral fractures (0.52, 0.32-0.85) in those assigned to calcium. There were no between-group differences in BMD at 10 years at any site. The adverse cardiovascular outcomes observed in the 5-year trial did not persist post-trial.

CONCLUSION

Calcium supplementation for 5 years had no effect on total fracture incidence at 10 years. The positive benefits on BMD and the adverse cardiovascular effects did not persist once supplements were stopped.

The exchangeable calcium pool: physiology and pathophysiology in chronic kidney disease

Excessive soft tissue and vascular calcifications are typical complications of chronic kidney disease (CKD) and disorders of phosphate homeostasis are considered to be a major contributor to the pathogenesis. However, at least in some individuals, calcium administration also increases the risk, and furthermore, it is widely accepted that there is a link between bone disease and vascular pathology. In this review, we discuss the role of the bone exchangeable calcium pool (ECP) in the acute regulation of the serum calcium concentration (Ca(s)) in health and CKD. This pool is able to buffer an acute calcium load as well as to maintain a stable Ca(s) during acute calcium deprivation. Indeed, the minute-to-minute regulation of Ca(s) appears to depend exclusively on this mechanism without any obvious contribution of other factors like parathyroid hormone, which nonetheless define the Ca(s) steady state set point. It is tempting to speculate that a reduction of the bone ECP plasticity in some patients with CKD leads to short-lasting increases in Ca(s) above the individual mid- to long-term set point as observed during haemodialysis or after the ingestion of calcium-containing phosphate binders. This could contribute to and partially explain the propensity of these subjects to develop extraosseous calcifications. An improved understanding of the processes involved and the availability of new techniques to assess the capacity of this pool, at least in dialysis patients, will make this area an attractive target for new investigations.

Nutrition and human health from a sex-gender perspective

Nutrition exerts a life-long impact on human health, and the interaction between nutrition and health has been known for centuries. The recent literature has suggested that nutrition could differently influence the health of male and female individuals. Until the last decade of the 20th century, research on women has been neglected, and the results obtained in men have been directly translated to women in both the medicine and nutrition fields. Consequently, most modern guidelines are based on studies predominantly conducted on men. However, there are many sex-gender differences that are the result of multifactorial inputs, including gene repertoires, sex steroid hormones, and environmental factors (e.g., food components). The effects of these different inputs in male and female physiology will be different in different periods of ontogenetic development as well as during pregnancy and the ovarian cycle in females, which are also age dependent. As a result, different strategies have evolved to maintain male and female body homeostasis, which, in turn, implies that there are important differences in the bioavailability, metabolism, distribution, and elimination of foods and beverages in males and females. This article will review some of these differences underlying the impact of food components on the risk of developing diseases from a sex-gender perspective.