Phosphorus and calcium: a review for the adult nutrition support clinician

A Comprehensive Review on Shilajit: What We Know about Its Chemical Composition

Shilajit, a natural material known for thousands of years, is primarily famous because it was the main constituent used for the mummification of bodies by dynastic Egyptians. However, for millennia, it has also been an important drug and supplement in traditional and modern medicine. A full search of Shilajit in the literature, reveals that its chemical composition is not known with certainty. That's due to the fact that surprisingly, no comprehensive chemical analysis has ever been performed to find all the chemicals and species present in it. Moreover, its source is not known; some believe that it is formed from dead plant residues or animal excrements, and some others believe it is a mineral secreted from rocks gradually. In this review article, it is tried to gather chemical property information available regarding this soft, mysterious black material to clarify what it is composed of and what formulation commercial supplements and drugs based on Shilajit may have. While there are many differences in the chemical compositions of Shilajit from various regions, it has been discovered that more than 80% of weight of Shilajit is mainly composed of humic substances and almost 20% of its weight consists of calcium, potassium, and magnesium. It also contains amino acids (mainly glycine) and proteins, fatty acids, bioactive compounds such as caffeic acid and gallic acid, and heavy metals including chromium, selenium, and cobalt.

Diet-Wide Association, Genetic Susceptibility and Colorectal Cancer Risk: A Prospective Cohort Study

BACKGROUND

Both genetic and dietary factors play significant roles in the etiology of colorectal cancer (CRC). To evaluate the relationship between certain food exposures and the risk of CRC, we carried out a large-scale association analysis in the UK Biobank.

METHODS

The associations of 139 foods and nutrients' intake with CRC risk were assessed among 118,210 participants. A polygenic risk score (PRS) of CRC was created to explore any interaction between dietary factors and genetic susceptibility in CRC risk. The hazard ratio (HR) and 95% confidence interval (CI) of CRC risk linked to dietary variables and PRS were estimated using Cox regression models. Multiple comparisons were corrected using the error discovery rate (FDR).

RESULTS

During a mean follow-up of 12.8 years, 1466 incidents of CRC were identified. In the UK Biobank, alcohol and white bread were associated with increased CRC risk, and their HRs were 1.08 (95% CI: 1.03-1.14; FDRP = 0.028) and 1.10 (95% CI: 1.05-1.16; FDRP = 0.003), whereas dietary fiber, calcium, magnesium, phosphorus, and manganese intakes were inversely associated. We found no evidence of any PRS-nutrient interaction relationship in relation to CRC risk.

CONCLUSIONS

Our results show that higher intakes of alcohol and white bread are associated with increased CRC risk, whilst dietary fiber, calcium, magnesium, phosphorus, and manganese are inversely associated.

Admission Serum Calcium Level and Short-Term Mortality After Acute Ischemic Stroke: A Secondary Analysis Based on a Norwegian Retrospective Cohort

Background

Disturbed serum calcium levels are related to the risk of stroke. However, previous studies exploring the correlation between serum calcium and the clinical outcome of ischemic stroke (IS) have shown inconsistent results.

Object

The study aimed to investigate the relationship between admission serum calcium and 30-day mortality in patients with IS.

Methods

A total of 876 IS patients from a Norwegian retrospective cohort were included for secondary analysis. The exposure variable and the primary outcome were albumin-corrected serum calcium (ACSC) at baseline and all-cause mortality within 30 days after the first admission, respectively. Multivariable logistic regression analysis was used to estimate the risk of 30-day mortality according to ACSC levels. Moreover, the potential presence of a non-linear relationship was evaluated using two-piecewise linear regression with a smoothing function and threshold level analysis. The stability of the results was evaluated by unadjusted and adjusted models.

Results

The result of multiple regression analysis showed that ACSC at baseline was positively associated with the incidence of 30-day mortality after adjusting for the potential confounders (age, gender, serum glucose, hypertension, atrial fibrillation/atrial flutter, renal insufficiency, heart failure, chronic obstructive pulmonary disease, pneumonia, paralysis, and aphasia) (OR = 2.43, 95% CI 1.43–4.12). When ACSC was translated into a categorical variable, the ORs and 95% CIs in the second to the fourth quartile vs. the first quartile were 1.23 (0.56, 2.69), 1.16 (0.51, 2.65), and 2.13 (1.04, 4.38), respectively (P for trend = 0.03). Moreover, the results of two-piecewise linear regression and curve-fitting revealed a linear relationship between ACSC and 30-day mortality.

Conclusion

ACSC is positively associated with 30-day mortality in IS patients, and the relationship between them is linear.

Multielemental Analysis of Bee Pollen, Propolis, and Royal Jelly Collected in West-Central Poland

Beehive products possess nutritional value and health-promoting properties and are recommended as so-called "superfoods". However, because of their natural origin, they may contain relevant elemental contaminants. Therefore, to assess the quality of bee products, we examined concentrations of a broad range of 24 selected elements in propolis, bee pollen, and royal jelly. The quantitative analyses were performed with inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES) techniques. The results of our research indicate that bee products contain essential macronutrients (i.e., K, P, and S) and micronutrients (i.e., Zn and Fe) in concentrations depending on the products' type. However, the presence of toxic heavy metals makes it necessary to test the quality of bee products before using them as dietary supplements. Bearing in mind that bee products are highly heterogenous and, depending on the environmental factors, differ in their elemental content, it is necessary to develop standards regulating the acceptable levels of inorganic pollutants. Furthermore, since bees and their products are considered to be an effective biomonitoring tool, our results may reflect the environment's condition in west-central Poland, affecting the health and well-being of both humans and bees.

Effects of 25(OH)D3 supplementation during late gestation on the serum biochemistry and reproductive performance of aged sows and newborn piglets

The purpose of this study was to investigate the effects of diet type (normal or low Ca and P diets) and 25(OH)D₃ supplementation (with or with not 2000 IU/kg 25(OH)D₃ ) during late gestation on the serum biochemistry and reproductive performance of aged sows and newborn piglets. A total of 40 sows, which are at their 7th parity, were divided into four groups: control group (standard diet), low Ca group, 25(OH)D₃ group and low Ca plus 25(OH)D₃ group respectively (10 in each group). The blood of sows on day 100 and 114 of gestation and newborn piglets was collected for serum biochemical analyses. Results showed that the reproductive performance of sows was not influenced by diet type or 25(OH)D₃ supplementation (p > 0.05). And the addition of 25(OH)D₃ to diet low Ca group caused that the content of serum TG in sows on day 100 of gestation was not different from that of the control group (p > 0.05). The addition of 25(OH)D₃ significantly decreases the content of serum TG in sows on day 114 of gestation (p < 0.05). The addition of 25(OH)D₃ significantly increased the content of serum UREA and CREA in newborn piglets (p < 0.05). Overall, feeding 2000 IU/kg 25(OH)D₃ to aged sows at late gestation had no effects on reproductive performance, but partly contributed to keeping serum TG balance in sows and may indicate increased pressure on kidneys in newborn piglets.

Serum calcium levels correlates with coronary artery disease outcomes

Background

Effect of serum calcium levels on prognosis of patients with coronary artery disease (CAD) is not well evaluated. We aimed to assess the associations of baseline serum calcium levels with both short-term and long-term outcomes in CAD patients.

Methods

This study included 3,109 consecutive patients with angiographically confirmed CAD. Patients were categorized into quartiles according to admission serum calcium. Multivariable regression analysis was used to determine the association of serum calcium with mortality.

Results

Compared to patients in the lowest quartile of serum calcium, patients in upper quartiles were presented with lower all-cause mortality (Hazard ratios [HRs] were -0.636 [95% CI: -0.424 to -0.954], -0.545 [95% CI: -0.351 to -0.846] and -0.641 [95% CI: -0.450 to -0.913] for three upper quartiles versus lowest quartile respectively), cardiovascular mortality (HRs 0.594 [0.368-0.961], 0.261 [0.124-0.551] and 0.407 [0.229-0.725]), and in-hospital mortality (Odd ratios [ORs] 0.391 [0.188-0.812], 0.231 [0.072-0.501] and 0.223 [0.093-0.534]). Consistent associations between serum calcium and long-term mortality were also obtained in subgroup analysis of ACS patients, stable CAD patients and discharged patients.

Conclusions

Serum calcium is inversely associated with CAD and can independently predict both in-hospital and long-term mortality among CAD patients.

Comparison of the Effect of Enteral Feeding through the Bolus and Continuous Methods on Serum Phosphorus and Glucose Levels in Patients with Mechanical Ventilation: A Randomized Clinical Trial

Introduction

Patients who are under mechanical ventilation in intensive care units need to have nutritional support. Also, feeding methods affect serum phosphorus and glucose levels, which are very important in weaning patients off the ventilator. Thus, this study is to compare the effects of both bolus and continuous enteral feeding methods on serum phosphorus and glucose levels in patients with mechanical ventilation.

Methods

In this clinical trial study, 34 patients in the intensive care unit of Imam Khomeini Hospital affiliated to the Tehran University of Medical Sciences satisfied inclusion criteria and were randomly divided into control and intervention groups. Sampling was done between October and February 2018. The intervention group received continuous enteral feeding for one week, and the control group received nutrition by the bolus method. The blood glucose level was measured every six hours, and the serum phosphorus level was recorded at the beginning and the end of the intervention, based on the data entry form with respect to all ethical considerations. Data analysis was done by SPSS-20 software.

Results

The serum phosphorus level was significantly increased in the intervention group (P=0.004) and in the control group (P < 0.001) and was compared with the previous intervention. No significant difference was found between the intervention and control groups before and after the intervention (P=0.22) and also one week after the intervention (P=0.14). There was also no significant difference between the glucose levels from day 1 to day 7 in the control group (P=0.33) and the intervention group (P=0.086). Discussion. Nutritional support in both bolus and continuous methods increased the serum phosphorus level. It indicates the importance of the nutritional method in controlling the phosphorus level in critically ill patients. However, there was no difference between the effects of dietary methods on blood glucose control.

Conventional and novel impacts of ferric citrate on iron deficiency anemia and phosphorus metabolism in rats

Ferric citrate is an oral iron-based phosphate binder, being known to affect iron status and improve iron deficiency anemia (IDA) in chronic kidney disease (CKD) patients. We examined whether oral administration of ferric citrate could change iron status and improve anemia without affecting phosphorus metabolism in iron deficiency anemia rats. In Normal rat study, normal rats were fed a diet containing 0.3 or 3% ferric citrate for 11 days for setting the dose and administration period of ferric citrate. The effects of ferric citrate on iron status- and phosphorus metabolism-related parameters were evaluated using blood and urine samples. Next, an iron deficiency anemia was induced by feeding iron-depleted diet in rats. After 7 days of starting the iron-depleted diet, 0.3% ferric citrate was administered for 7 days by dietary admixture. Iron status- and phosphorus metabolism-related parameters were evaluated with blood and urine samples. In Normal rat study, 3% ferric citrate treatment increased serum iron level and transferrin saturation (TSAT), and decreased serum phosphorus level, intact fibroblast growth factor 23 (iFGF23) level, and urinary phosphorus excretion, but 0.3% ferric citrate treatment showed no effects. On the other hand, in Iron deficiency anemia rat study, 0.3% ferric citrate treatment increased iron status-related parameters and improved anemia, but did not show any apparent changes in phosphorus metabolism-related parameters. In conclusion, ferric citrate could have hematopoietic effects without affecting phosphorus metabolism, and could be a potential option for the treatment of IDA in patients without CKD.

Serum calcium levels independently predict in-hospital mortality in patients with acute myocardial infarction

BACKGROUND AND AIM

Serum calcium levels (sCa) were reported to be associated with cardiovascular risk factors, incidence of coronary artery disease and acute myocardial infarction (AMI). The current study evaluated the association between sCa and in-hospital mortality among AMI patients.

METHODS AND RESULTS

Patients admitted in a tertiary medical center for AMI throughout 2002-2012 were analyzed. For each patient, mean sCa, corrected to albumin, was calculated and categorized to seven equally-sized groups: <8.9, 8.9-9.12, 9.12-9.3, 9.3-9.44, 9.44-9.62, 9.62-9.86, ≥9.86 mg/dL. The primary outcome was all-cause in-hospital mortality. Out of 12,121 AMI patients, 11,446 were included, mean age 67.1 ± 14 years, 68% Males. Mean number of sCa values for patient was 4.2 ± 7.3. Mean sCa was 9.4 ± 0.53 mg/dL, range 5.6-13.2 mg/dL sCa was significantly associated with cardiovascular risk-factors, in-hospital complications, more frequent 3-vessel coronary artery disease and decreased rate of revascularization, often in a U-shaped association. Overall 794 (6.9%) patients died in-hospital. Multivariate analysis showed a significant U-shaped association between sCa and in-hospital mortality with sCa below 9.12 mg/dL and above 9.86 mg/dL as independent predictors of significantly increased in-hospital mortality: OR = 2.4 (95% CI:1.7-3.3) and 1.7 (95%CI:1.2-2.4), for Ca<8.9 and Ca≥9.86 mg/dL respectively p < 0.01, as compared with middle rage sCa group (9.3-9.44 mg/dL).

CONCLUSION

sCa is an independent predictor of in-hospital mortality in patients with AMI with a U-shaped association. Both increased and decreased sCa levels are associated with increased risk of in-hospital mortality.

An integrative review of the methodology and findings regarding dietary adherence in end stage kidney disease

BACKGROUND

Dietary modification is an important component of the management of end stage kidney disease (ESKD). The diet for ESKD involves modifying energy and protein intake, and altering sodium, phosphate, potassium and fluid intake. There have been no comprehensive reviews to date on this topic. The aims of this integrative review were to (i) describe the methods used to measure dietary adherence (ii) determine the rate of dietary adherence and (iii) describe factors associated with dietary adherence in ESKD.

METHODS

The Web of Science and Scopus databases were searched using the search terms 'adherence' and 'end stage kidney disease'. Of the 787 potentially eligible papers retrieved, 60 papers of 24,743 patients were included in this review. Of these papers, 44 reported the rate of dietary adherence and 44 papers described factors associated with adherence.

RESULTS

Most of the evidence regarding dietary adherence is derived from studies of hemodialysis patients (72% of patients). The most common method of measuring dietary adherence in ESKD was subjective techniques (e.g. food diaries or adherence questionnaires). This was followed by indirect methods (e.g. serum potassium, phosphate or interdialytic weight gain). The weighted mean adherence rate to ESKD dietary recommendations was 31.5% and 68.5% for fluid recommendations. Adherence to protein, sodium, phosphate, and potassium recommendations were highly variable due to differences in measurement methods used, and were often derived from a limited evidence base. Socioeconomic status, age, social support and self-efficacy were associated with dietary adherence. However, factors such as taste, the impact of the diet on social eating occasions; and dietetic staffing also appear to play a role in dietary adherence.

CONCLUSION

Dietary adherence rates in people with ESKD are suboptimal. Further research is required on dietary adherence in patients with ESKD from different social, educational, economic and ethnic groups. This research may identify other factors which may impact upon adherence, and could be used to inform the design of future strategies to improve dietary adherence. Future research that reports not just the rate of adherence to individual components of the nutrient prescription but also the overall quality of the diet would be useful.

Parenteral Nutrition Basics for the Clinician Caring for the Adult Patient

Parenteral nutrition (PN) is a life-sustaining therapy providing nutrients to individuals with impaired intestinal tract function and enteral access challenges. It is one of the most complex prescriptions written routinely in the hospital and home care settings. This article is to aid the nutrition support clinician in the safe provision of PN, including selecting appropriate patients for PN, vascular access, development of a PN admixture, appropriate therapy monitoring, recognition of preparation options, and awareness of preparation and stability concerns.

Admission Serum Calcium Levels Improve the GRACE Risk Score Prediction of Hospital Mortality in Patients With Acute Coronary Syndrome

BACKGROUND

The Global Registry of Acute Coronary Events (GRACE) risk score has been extensively validated to predict risk during hospitalization in patients with acute coronary syndrome (ACS). Recently, serum calcium has been suggested as an independent predictor for in-hospital mortality in patients with ST-segment elevation myocardial infarction; however, the relationship between the 2 has not been evaluated.

HYPOTHESIS

The combination of GRACE risk score and serum calcium could provide better performance in risk prediction.

METHODS

The study enrolled 2229 consecutive patients with ACS. Independent predictors were identified by a multivariate logistic regression model. The incremental prognostic value added by serum calcium to the GRACE score was evaluated by receiver operating characteristic, net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

RESULTS

Patients in the upper quartiles of serum calcium presented with lower in-hospital mortality (odds ratios for 3 upper quartiles vs lowest quartile, respectively: 0.443, 95% confidence interval [CI]: 0.206-0.953; 0.243, 95% CI: 0.090-0.654; and 0.210, 95% CI: 0.082-0.538). Area under the curve increased significantly after adding serum calcium to the GRACE score (0.685 vs 0.746; Z = 2.617, P = 0.009). Furthermore, inclusion of serum calcium in the GRACE score enhanced NRI (0.524; P = 0.009) and IDI (0.011; P = 0.003).

CONCLUSIONS

Lower serum calcium level on admission is a possible indicator of increased risk of in-hospital mortality in ACS patients. Inclusion of serum calcium in the GRACE score may lead to a more accurate prediction of this risk. Large prospective studies are needed to confirm this finding.

Investigation of the roles of trace elements during hepatitis C virus infection using protein-protein interactions and a shortest path algorithm

BACKGROUND

Hepatitis is a type of infectious disease that induces inflammation of the liver without pinpointing a particular pathogen or pathogenesis. Type C hepatitis, as a type of hepatitis, has been reported to induce cirrhosis and hepatocellular carcinoma within a very short amount of time. It is a great threat to human health. Some studies have revealed that trace elements are associated with infection with and immune rejection against hepatitis C virus (HCV). However, the mechanism underlying this phenomenon is still unclear.

METHODS

In this study, we aimed to expand our knowledge of this phenomenon by designing a computational method to identify genes that may be related to both HCV and trace element metabolic processes. The searching procedure included three stages. First, a shortest path algorithm was applied to a large network, constructed by protein-protein interactions, to identify potential genes of interest. Second, a permutation test was executed to exclude false discoveries. Finally, some rules based on the betweenness and associations between candidate genes and HCV and trace elements were built to select core genes among the remaining genes.

RESULTS

12 lists of genes, corresponding to 12 types of trace elements, were obtained. These genes are deemed to be associated with HCV infection and trace elements metabolism.

CONCLUSIONS

The analyses indicate that some genes may be related to both HCV and trace element metabolic processes, further confirming the associations between HCV and trace elements. The method was further tested on another set of HCV genes, the results indicate that this method is quite robustness.

GENERAL SIGNIFICANCE

The newly found genes may partially reveal unknown mechanisms between HCV infection and trace element metabolism. This article is part of a Special Issue entitled "System Genetics" Guest Editor: Dr. Yudong Cai and Dr. Tao Huang.

Comparison of Calcium Intake Status by Region and Socioeconomic Status in Korea: The 2011-2013 Korea National Health and Nutrition Examination Survey

Background

Calcium is an essential element nutrient in our body, and insufficient calcium intake is very common in Korean. Socioeconomic status (SES) is known to be associated with quality of diet and health. The purpose of this study was to compare between calcium intake by region and SES.

Methods

This study used data from a nationally represented sample of Koreans (n=19,249) from 2011 to 2013 Korea National Health and Nutrition Examination Survey. We were divided into six regions: Seoul and Gyeonggi-do, Gangwon-do, Chungcheong-do, Jeolla-do, Gyeongsang-do, and Jeju-do. Daily calcium intake and dietary quality based on 24 hr recall data was calculated and analyzed by the sex, age, SES.

Results

The regions with the highest calcium intakes in both males and females were Seoul and Gyeonggi-do. The age groups with a significant difference in calcium intake, nutrient adequacy ratio, and nutrient density by region were 14 to 19, 20 to 29, and ≥65 years. Calcium intake and dietary quality were lowest in the low household income group. In terms of being a recipient of the dietary life supply, the calcium intake and dietary quality of the recipient group was low.

Conclusions

We found that daily calcium intake was very different by region and was significantly lower in region with lower SES. The findings of this study suggest social inequalities in calcium intake by region can be addressed in the development and implementation of tailored nutritional interventions to promote calcium nutritional status of Koreans.