Rapid assessment of dietary calcium intake

Recommended calcium intake in adults and children with chronic kidney disease-a European consensus statement

Mineral and bone disorders (MBD) are common in patients with chronic kidney disease (CKD), contributing to significant morbidity and mortality. For several decades, the first-line approach to controlling hyperparathyroidism in CKD was by exogenous calcium loading. Since the turn of the millennium, however, a growing awareness of vascular calcification risk has led to a paradigm shift in management and a move away from calcium-based phosphate binders. As a consequence, contemporary CKD patients may be at risk of a negative calcium balance, which, in turn, may compromise bone health, contributing to renal bone disease and increased fracture risk. A calcium intake below a certain threshold may be as problematic as a high intake, worsening the MBD syndrome of CKD, but is not addressed in current clinical practice guidelines. The CKD-MBD and European Renal Nutrition working groups of the European Renal Association (ERA), together with the CKD-MBD and Dialysis working groups of the European Society for Pediatric Nephrology (ESPN), developed key evidence points and clinical practice points on calcium management in children and adults with CKD across stages of disease. These were reviewed by a Delphi panel consisting of ERA and ESPN working groups members. The main clinical practice points include a suggested total calcium intake from diet and medications of 800-1000 mg/day and not exceeding 1500 mg/day to maintain a neutral calcium balance in adults with CKD. In children with CKD, total calcium intake should be kept within the age-appropriate normal range. These statements provide information and may assist in decision-making, but in the absence of high-level evidence must be carefully considered and adapted to individual patient needs.

Approach to nutritional rickets

Rickets is the disease of a growing skeleton and results from impaired apoptosis of hypertrophic chondrocytes and mineralization of the growth plate. Nutritionally induced rickets, secondary to vitamin D and/or calcium deficiency, remains a major global problem. In this review, we discuss pathogenesis, clinical signs, investigation and management of nutritional rickets.

Uncoupling of Bone Turnover may Compromise Skeletal Health of Young Patients With Haemophilia A

There is evidence that bone mass is decreased and bone metabolism is dysregulated in children with haemophilia (CWH). The objective of this study was to investigate the impact of haemophilia on skeletal health in children, with regards to bone mineral density (BMD) and metabolic bone profile. This study included 51 male CWH A. Dual-energy X-ray absorptiometry (DXA) was performed to assess BMD in lumbar spine (LS) and total body less head (TBLH) and Z-scores were calculated (low BMD Z-score<-2, low-normal BMD Z-score between -1 and -2). Serum levels of osteocalcin (OC), procollagen type I C-terminal propeptide (PICP), bone alkaline phosphatase (bALP), bone tartrate-resistant acid phosphatase 5b (TRAP5b), vitamin D, parathormone (PTH), urinary calcium/creatinine (uCa/uCr) and urine deoxypyridinoline/creatinine (uDPD/uCr) were measured. Mean BMD Z-scores were lower than predicted at both sites of measurement. More specifically, 10% of CWH A had low and 20% low-normal BMD Z-scores in LS, whereas 9.1% had low-normal TBLH BMD Z-scores and there were no patients with low BMD Z-scores at this site of measurement. 36.7% of CWH had low vitamin D levels and 19.6% had a history of fracture. Also, patients with haemophilia had lower OC and higher uDPD/uCr levels while OC positively correlated to BMD Z-scores and uDPD/uCr negatively correlated to BMD Z-scores at both sites. No statistically significant differences were observed with regards to mode of treatment, number of haemorrhages and the presence of target-joints. CWH A had decreased BMD Z-scores at both sites with an uncoupling of bone turnover LS BMD seemed to be more affected than TBLH BMD.

Nutritional rickets & osteomalacia: A practical approach to management

Defective mineralization of the growth plate and preformed osteoid result in rickets and osteomalacia, respectively. The leading cause of rickets worldwide is solar vitamin D deficiency and/or dietary calcium deficiency collectively termed as nutritional rickets. Vitamin D deficiency predominates in high-latitude countries in at-risk groups (dark skin, reduced sun exposure, infants and pregnant and lactating women) but is emerging in some tropical countries due to sun avoidance behaviour. Calcium deficiency predominates in tropical countries, especially in the malnourished population. Nutritional rickets can have devastating health consequences beyond bony deformities (swollen wrist and ankle joints, rachitic rosary, soft skull, stunting and bowing) and include life-threatening hypocalcaemic complications of seizures and, in infancy, heart failure due to dilated cardiomyopathy. In children, diagnosis of rickets (always associated with osteomalacia) is confirmed on radiographs (cupping and flaring of metaphyses) and should be suspected in high risk individuals with the above clinical manifestations in the presence of abnormal blood biochemistry (high alkaline phosphatase and parathyroid hormone, low 25-hydroxyvitamin D and calcium and/or low phosphate). In adults or adolescents with closed growth plates, osteomalacia presents with non-specific symptoms (fatigue, malaise and muscle weakness) and abnormal blood biochemistry, but only in extreme cases, it is associated with radiographic findings of Looser's zone fractures. Bone biopsies could confirm osteomalacia at earlier disease stages, for definitive diagnosis. Treatment includes high-dose cholecalciferol or ergocalciferol daily for a minimum of 12 wk or stoss therapy in exceptional circumstances, each followed by lifelong maintenance supplementation. In addition, adequate calcium intake through diet or supplementation should be ensured. Preventative approaches should be tailored to the population needs and incorporate multiple strategies including targeted vitamin D supplementation of at-risk groups and food fortification with vitamin D and/or calcium. Economically, food fortification is certainly the most cost-effective way forward.

Validation of a six-item dietary calcium screening tool among HIV patients in China

OBJECTIVE

Individuals with HIV are at increased risk for osteoporosis. A healthy diet with adequate Ca is recommended to promote bone health. However, lengthy nutritional assessments pose barriers to routine screenings in clinical practice. This study aimed to examine the validity and reproducibility of a six-item dietary Ca screening tool among Chinese individuals with HIV.

DESIGN

We conducted a two time-point study in an outpatient setting. Volunteers self-administered the six-item tool upon enrolment and again at 1-month follow-up. At baseline, participants also completed a validated FFQ and surveys regarding demographic and clinical risk factors.

SETTING

Beijing, China; Shenzhen, Guangdong, China.

PARTICIPANTS

Upon enrolment, 127 individuals with HIV participated in the study, of whom 83 completed the follow-up screening.

RESULTS

Mean age of participants was 35·2 (sd 9·3) years, average BMI was 22·8 (sd 3·8) kg/m2 and 89 % were men. Among the participants, 54·7 % reported Ca intake less than 800 mg/d. The six-item tool demonstrated fair-to-moderate relative validity with a correlation of 0·39 and 75·7 % of subjects classified in same/adjacent quartiles as the reference, and moderate-to-good reproducibility with a correlation of 0·60 and 83·1 % of subjects classified in same/adjacent quartiles. Finally, receiver operating characteristic analyses yielded a sensitivity of 87·0 % and a specificity of 39·4 % with optimised cut-off level.

CONCLUSIONS

The six-item tool presented adequate validity and reproducibility to identify individuals with low Ca intake among the target population, providing a convenient instrument for categorising Ca intake in clinical practice, prompting referrals for further assessment, and raising awareness of dietary Ca in bone disease prevention.

The dietary management of calcium and phosphate in children with CKD stages 2-5 and on dialysis-clinical practice recommendation from the Pediatric Renal Nutrition Taskforce

In children with chronic kidney disease (CKD), optimal control of bone and mineral homeostasis is essential, not only for the prevention of debilitating skeletal complications and achieving adequate growth but also for preventing vascular calcification and cardiovascular disease. Complications of mineral bone disease (MBD) are common and contribute to the high morbidity and mortality seen in children with CKD. Although several studies describe the prevalence of abnormal calcium, phosphate, parathyroid hormone, and vitamin D levels as well as associated clinical and radiological complications and their medical management, little is known about the dietary requirements and management of calcium (Ca) and phosphate (P) in children with CKD. The Pediatric Renal Nutrition Taskforce (PRNT) is an international team of pediatric renal dietitians and pediatric nephrologists, who develop clinical practice recommendations (CPRs) for the nutritional management of various aspects of renal disease management in children. We present CPRs for the dietary intake of Ca and P in children with CKD stages 2-5 and on dialysis (CKD2-5D), describing the common Ca- and P-containing foods, the assessment of dietary Ca and P intake, requirements for Ca and P in healthy children and necessary modifications for children with CKD2-5D, and dietary management of hypo- and hypercalcemia and hyperphosphatemia. The statements have been graded, and statements with a low grade or those that are opinion-based must be carefully considered and adapted to individual patient needs based on the clinical judgment of the treating physician and dietitian. These CPRs will be regularly audited and updated by the PRNT.

Shedding Light on Vitamin D Status and Its Complexities during Pregnancy, Infancy and Childhood: An Australian Perspective

Ensuring that the entire Australian population is Vitamin D sufficient is challenging, given the wide range of latitudes spanned by the country, its multicultural population and highly urbanised lifestyle of the majority of its population. Specific issues related to the unique aspects of vitamin D metabolism during pregnancy and infancy further complicate how best to develop a universally safe and effective public health policy to ensure vitamin D adequacy for all. Furthermore, as Australia is considered a “sunny country”, it does not yet have a national vitamin D food supplementation policy. Rickets remains very uncommon in Australian infants and children, however it has been recognised for decades that infants of newly arrived immigrants remain particularly at risk. Yet vitamin D deficiency rickets is entirely preventable, with the caveat that when rickets occurs in the absence of preexisting risk factors and/or is poorly responsive to adequate treatment, consideration needs to be given to genetic forms of rickets.

Assessment of dietary calcium intake of university students: a pilot study in Turkey

The aim of this study was to adapt the rapid assessment method (RAM) and International Osteoporosis Foundation Food Frequency Questionnaire (IOF FFQ) tools, used for the assessment of daily calcium intake in university students, and to compare the data obtained using 24-h recall (24-HR) data. There was a moderate positive correlation between the RAM and IOF.

PURPOSE/INTRODUCTION

Calcium is an essential mineral that plays vital roles in metabolism and it is very important to accurately assess the amount of calcium intake on the diet. It was aimed to assess the daily calcium intake of university students by two different food frequency questionnaires (FFQs) developed specifically for evaluating calcium intake, and 24-h recall method.

METHOD

The study was conducted with a total of 183 female university students aged 18-31. In the study, a questionnaire including sociodemographic information, a calcium calculator, IOF FFQ, prepared in seven different languages, and RAM was applied. In addition, 1-day food consumption records were obtained using 24-HR method.

RESULTS

The daily average calcium intakes of individuals according to two different food frequency questionnaires (RAM FFQ and IOF FFQ) and 24-h food consumption records are respectively 1594.2 ± 810.9, 897.9 ± 368.4, and 605.6 ± 278.3 mg. When the daily average calcium intake was compared with the other two methods, RAM was found to be statistically higher (p < 0.001). There was a moderate positive correlation between the RAM and IOF FFQ methods (Pearson r = 0.528, p < 0.01) and the intra-class correlation coefficient between these two methods was found to be significant and moderate (ICC r = 0.452, p < 0.01).

CONCLUSION

In terms of protecting and improving health, it is important to make suggestions using fast and short tools to ensure adequate calcium intake from young age. It is thought that FFQs are the most appropriate methods in assessing daily calcium intake for this study group because it is observed that the list of foods and the amount of portions in FFQs reduce the problem of remembering at 24-h method to a great extent.

Rickets

Rickets is a bone disease associated with abnormal serum calcium and phosphate levels. The clinical presentation is heterogeneous and depends on the age of onset and pathogenesis but includes bowing deformities of the legs, short stature and widening of joints. The disorder can be caused by nutritional deficiencies or genetic defects. Mutations in genes encoding proteins involved in vitamin D metabolism or action, fibroblast growth factor 23 (FGF23) production or degradation, renal phosphate handling or bone mineralization have been identified. The prevalence of nutritional rickets has substantially declined compared with the prevalence 200 years ago, but the condition has been re-emerging even in some well-resourced countries; prematurely born infants or breastfed infants who have dark skin types are particularly at risk. Diagnosis is usually established by medical history, physical examination, biochemical tests and radiography. Prevention is possible only for nutritional rickets and includes supplementation or food fortification with calcium and vitamin D either alone or in combination with sunlight exposure. Treatment of typical nutritional rickets includes calcium and/or vitamin D supplementation, although instances infrequently occur in which phosphate repletion may be necessary. Management of heritable types of rickets associated with defects in vitamin D metabolism or activation involves the administration of vitamin D metabolites. Oral phosphate supplementation is usually indicated for FGF23-independent phosphopenic rickets, whereas the conventional treatment of FGF23-dependent types of rickets includes a combination of phosphate and activated vitamin D; an anti-FGF23 antibody has shown promising results and is under further study.

Nutritional Rickets and Osteomalacia in the Twenty-first Century: Revised Concepts, Public Health, and Prevention Strategies

PURPOSE OF REVIEW

Nutritional rickets and osteomalacia are common in dark-skinned and migrant populations. Their global incidence is rising due to changing population demographics, failing prevention policies and missing implementation strategies. The calcium deprivation spectrum has hypocalcaemic (seizures, tetany and dilated cardiomyopathy) and late hypophosphataemic (rickets, osteomalacia and muscle weakness) complications. This article reviews sustainable prevention strategies and identifies areas for future research.

RECENT FINDINGS

The global rickets consensus recognises the equal contribution of vitamin D and dietary calcium in the causation of calcium deprivation and provides a three stage categorisation for sufficiency, insufficiency and deficiency. For rickets prevention, 400 IU daily is recommended for all infants from birth and 600 IU in pregnancy, alongside monitoring in antenatal and child health surveillance programmes. High-risk populations require lifelong supplementation and food fortification with vitamin D or calcium. Future research should identify the true prevalence of rickets and osteomalacia, their role in bone fragility and infant mortality, and best screening and public health prevention tools.