Calcium Disorders in the Emergency Department: Independent Risk Factors for Mortality

Use of Albumin-Adjusted Calcium Measurements in Clinical Practice

Importance

Using albumin-adjusted calcium is commonly recommended for for measuring calcium, but with little empirical evidence to support the practice.

Objective

To assess the correlation between total calcium measurements (with or without adjustment) vs the ionized calcium level as a reference standard.

Design, Setting, and Participants

This was a population-based cross-sectional study in the province of Alberta, Canada, including adults tested for serum total calcium and ionized calcium simultaneously between January 1, 2013, and October 31, 2019. Statistical analysis was performed from March 2023 to October 2024.

Main Measures and Outcomes

The correlation between unadjusted and adjusted total calcium measurements (using 10 formulas) and the ionized calcium level was evaluated, along with the potential association with the classification of calcium status.

Results

Among 22 658 patients included, 11 889 (52.5%) were female and 10 769 (47.5%) were male; the median (IQR) age was 60 (47-72) years. The unadjusted total calcium (R2 = 71.7%; 95% CI, 71.1%-72.2%) had a stronger correlation with ionized calcium than the commonly used simplified Payne formula (ie, total calcium [mmol/L] + 0.02 [40 - albumin (g/L)]) (R2 = 68.9%; 95% CI, 68.0%-69.6%) and correlated similarly to other formulas (Payne: lowest R2 = 60.3%; 95% CI, 59.3%-61.3%; and James: highest R2 = 76.7%; 95% CI, 76.1%-77.3%). When classifying patients into categories of hypocalcemia, normocalcemia, or hypercalcemia, unadjusted total calcium had the best overall agreement (74.5%) with ionized calcium compared with albumin-adjusted calcium using the original Payne and simplified Payne formulas (agreement 63.0% and 58.7%, respectively). Misclassification using the adjustment formulas was worse in the presence of hypoalbuminemia (albumin level <30 g/L).

Conclusions and Relevance

In this cross-sectional study drawn from a contemporaneous population, there appeared to be heavy reliance on adjustment formulas for calcium in clinical practice with little gain but considerable risk of misclassification of true calcium status, especially in the presence of hypoalbuminemia. These results suggest that unadjusted total calcium was the best and most practical alternative to ionized calcium.

Severe hypocalcemia in the emergency department: a retrospective cohort study of prevalence, etiology, treatment and outcome

The aim of this study was to evaluate the prevalence of severe hypocalcemia in patients attending the emergency department. Symptoms, causes, treatment, and outcome of severe hypocalcemia as well as course of calcium concentrations were assessed. This retrospective case series included all adult patients with measurements of serum calcium concentrations presenting to the emergency department of the Bürgerspital Solothurn between January 01 in 2017 and December 31 in 2020. Medical record reviews were performed of all patients with severe hypocalcemia, defined by a serum calcium concentration < 1.9 mmol/L, to assess clinical presentation and management. 1265 (3.95%) patients had a serum calcium concentration of < 2.1 mmol/L of which 139 (11%) had severe hypocalcemia of < 1.9 mmol/L. 113 patients had at least one measurement of albumin. Of these, 43 (3.4%) had an albumin-corrected serum calcium < 1.9 mmol/L defining true, severe hypocalcemia. Hypocalcemia was identified and documented in 35% of all cases. The mean serum calcium concentration was 1.74 ± 0.14 mmol/L. Calcium concentrations in malignancy-related hypocalcemia were similar to non-malignancy-related hypocalcemia. The main symptoms attributed to hypocalcemia were cardiac and neurologic. 12% of patients with severe hypocalcemia received intravenous and 23% oral calcium replacement. Active malignancy was the main cause of severe hypocalcemia in 28%, while in most cases, the main cause remained unclear. 41.9% of severely hypocalcemic patients reattended the emergency department for another episode of hypocalcemia within 1 year. Hypocalcemia is common in patients attending the emergency department, however, appears to be neglected frequently. The disorder is often a manifestation of severe disease, triggered by multiple causes. Calcium replacement was administered in less than half of the patients with severe hypocalcemia in this study. Due to frequent readmissions to the emergency department and a high mortality, increased awareness of the disorder and careful follow-up are desirable.

Large library docking identifies positive allosteric modulators of the calcium-sensing receptor

Positive allosteric modulator (PAM) drugs enhance the activation of the calcium-sensing receptor (CaSR) and suppress parathyroid hormone (PTH) secretion. Unfortunately, these hyperparathyroidism-treating drugs can induce hypocalcemia and arrhythmias. Seeking improved modulators, we docked libraries of 2.7 million and 1.2 billion molecules against the CaSR structure. The billion-molecule docking found PAMs with a 2.7-fold higher hit rate than the million-molecule library, with hits up to 37-fold more potent. Structure-based optimization led to nanomolar leads. In ex vivo organ assays, one of these PAMs was 100-fold more potent than the standard of care, cinacalcet, and reduced serum PTH levels in mice without the hypocalcemia typical of CaSR drugs. As determined from cryo-electron microscopy structures, the PAMs identified here promote CaSR conformations that more closely resemble the activated state than those induced by the established drugs.

Preoperative Serum Calcium Level Predicts Postoperative Mortality in Older Adult Patients with Hip Fracture: A Prospective Cohort Study of 2333 Patients

OBJECTIVES

Hip fractures are a significant cause of mortality among older adults. However, predictive markers for an unfavorable prognosis are still lacking. Serum calcium is an essential element in several biochemical reactions in the body. This study investigated the role of the preoperative serum calcium level as a prognostic parameter for postoperative mortality in older adult patients with hip fractures.

DESIGN

We conducted a prospective cohort study at the trauma center in our hospital, from January 1, 2015, to September 30, 2019. A total of 2333 older patients with hip fractures were recruited. This prospective cohort study was conducted in accordance with the criteria of STROCSS.

SETTING AND PARTICIPANTS

Older adult patients with hip fractures were screened between January 2015 and September 2019 at the trauma center of our hospital.

METHODS

Demographic and clinical characteristics of the patients were collected. Linear and nonlinear multivariate Cox regression models were used to identify the association between preoperative serum calcium level and all-cause mortality. All analyses were performed using EmpowerStats and the R software.

RESULTS

A total of 2333 older adult patients with hip fractures were included in the study. The mean follow-up was 37.5 months. Overall, 770 patients (33%) died of all causes. The preoperative serum calcium concentrations were 2.18 ± 0.13 mmol/L. Linear multivariate Cox regression models showed that preoperative serum calcium levels were associated with mortality [hazard ratio (HR) 0.37, 95% CI 0.21-0.67; P = .0009] after adjusting for confounders. However, the linear association was unstable, and nonlinearity was identified. A preoperative serum calcium level of 2.3 mmol/L was an inflection point for prediction. When the preoperative serum calcium concentration was below 2.3 mmol/L, serum calcium concentration increased by 1 mmol/L, and mortality risk decreased by 77% (HR 0.23, 95% CI 0.13-0.43, P < .0001). In contrast, when the preoperative serum calcium concentration was more significant than 2.3 mmol/L, the mortality risk increased with serum calcium concentration (HR 6.27, 95% CI 1.65-23.74, P = .0069).

CONCLUSIONS AND IMPLICATIONS

The preoperative serum calcium level is nonlinearly associated with mortality in older adults with hip fractures, with a U-shaped association, and could be used as a potential predictor of prognosis.

Small vs. Large Library Docking for Positive Allosteric Modulators of the Calcium Sensing Receptor

Drugs acting as positive allosteric modulators (PAMs) to enhance the activation of the calcium sensing receptor (CaSR) and to suppress parathyroid hormone (PTH) secretion can treat hyperparathyroidism but suffer from side effects including hypocalcemia and arrhythmias. Seeking new CaSR modulators, we docked libraries of 2.7 million and 1.2 billion molecules against transforming pockets in the active-state receptor dimer structure. Consistent with simulations suggesting that docking improves with library size, billion-molecule docking found new PAMs with a hit rate that was 2.7-fold higher than the million-molecule library and with hits up to 37-fold more potent. Structure-based optimization of ligands from both campaigns led to nanomolar leads, one of which was advanced to animal testing. This PAM displays 100-fold the potency of the standard of care, cinacalcet, in ex vivo organ assays, and reduces serum PTH levels in mice by up to 80% without the hypocalcemia typical of CaSR drugs. Cryo-EM structures with the new PAMs show that they induce residue rearrangements in the binding pockets and promote CaSR dimer conformations that are closer to the G-protein coupled state compared to established drugs. These findings highlight the promise of large library docking for therapeutic leads, especially when combined with experimental structure determination and mechanism.

Acute Serum Calcium Level Changes Following Non-Massive Blood and Blood Product Transfusion in Emergency Department; a Cross-sectional Study

Introduction

The specific impact on calcium dynamics after non-massive blood transfusions remains relatively unexplored. This study aimed to compare pre- and post-transfusion calcium levels in patients receiving blood and blood product in the emergency department.

Methods

This is a single-center, prospective, cross-sectional study conducted at the Emergency Department of Gazi University Health Research and Application Center Hospital in Ankara, Turkey, from January 1, 2020, to August 31, 2020. The study included adult patients who underwent blood and blood product transfusions, and serum calcium levels were measured and compared from samples taken before and after transfusion.

Results

A total of 292 participants were enrolled in the study, with 242 participants included in the final analysis. The mean total calcium level was 8.41 ± 0.76 mg/dL before transfusion and 8.34 ± 0.71 mg/dL after transfusion (p=0.012). When examining the corrected calcium values after receiving blood products based on the type of blood products, participants who received apheresis platelets had a post-transfusion corrected calcium value of 8.26 ±0.41 mg/dL, with a pre-transfusion value of 9.09 ±0.49 mg/dL (p<0.01). The post-transfusion ionized calcium value for participants receiving apheresis was 1.04 ±0.08 mg/dL, compared to 1.15 ±0.09 mg/dL for those who did not receive apheresis (p=0.049). There was a significant relationship between receiving fresh frozen plasma and post-transfusion ionized calcium values (p=0.024).

Conclusion

This study demonstrated that transfusion-associated hypocalcemia can occur even at mild levels in patients receiving blood and blood product transfusions in the emergency department. However, it is suggested that the clinical effects of hypocalcemia, even when occurring based on the type and quantity of blood products, are minimal and negligible.

Prevalence and Etiological Profile of Hypercalcemia in Hospitalized Adult Patients and Association with Mortality

Background

The etiology of hypercalcemia varies according to the clinical setting. Hitherto, data on the prevalence and profile of hypercalcemia in hospitalized Asian-Indian patients are limited. Hence, we conducted a prospective observational study to determine the prevalence and etiological profile of hypercalcemia in hospitalized Asian-Indian patients and its association with 6-month mortality.

Materials and Methods

We conducted a prospective observational study wherein all the patients (aged >12 years) admitted to the general medicine wards of a tertiary care hospital in North India between January 1, 2016, and June 30, 2017, were screened. Finally, patients with sustained hypercalcemia (defined as corrected serum total calcium ≥10.4 mg/dl documented twice at least 24 h apart) were included in this study. These patients were followed up throughout the hospital course and thereafter till 6 months from the date of discharge.

Results

Out of 9902 patients, 150 patients had sustained hypercalcemia (prevalence 1.5%). The most common cause of hypercalcemia was malignancy (41.3%), followed by primary hyperparathyroidism (PHPT, 32.7%). Vitamin D intoxication was responsible for hypercalcemia in 8.7% of patients; 2.7% of patients had hypercalcemia of advanced chronic liver disease. Nevertheless, a definite etiology could not be identified in 7.3% of the patients with hypercalcemia. At the end of 6 months of follow-up, the cumulative mortality rate was 28%. Underlying malignancy and higher calcium levels were the significant determinants of mortality.

Conclusions

The prevalence of hypercalcemia in Asian-Indian patients admitted to a tertiary care hospital was 1.5%. The most common etiology was malignancy, followed by PHPT.

Low Plasma Ionized Calcium Is Associated With Increased Mortality: A Population-based Study of 106 768 Individuals

CONTEXT

Low circulating total calcium or albumin-adjusted calcium has been associated with higher mortality, especially in hospital settings; however, these measures tend to misclassify patients with derangements in calcium homeostasis.

OBJECTIVE

As the association of the biologically active ionized calcium with mortality is poorly elucidated, we tested the hypothesis that low plasma ionized calcium is associated with higher risk of all-cause and cause-specific mortality in the general population.

METHODS

We included 106 768 individuals from the Copenhagen General Population Study. Information on all-cause and cause-specific mortality was from registries and risks were calculated using Cox regression and competing-risks regression by the STATA command stcompet.

RESULTS

During a median follow-up period of 9.2 years, 11 269 individuals died. Each 0.1 mmol/L lower plasma ionized calcium below the median of 1.21 mmol/L was associated with a multivariable adjusted hazard ratio of 1.23 (95% CI, 1.10-1.38) for all-cause mortality. Corresponding hazard ratios for cancer and other mortality were 1.29 (1.06-1.57) and 1.24 (1.01-1.53), respectively. In contrast, for cardiovascular mortality, only high plasma ionized calcium was associated with mortality with a hazard ratio of 1.17 (1.02-1.35) per 0.1 mmol/L higher plasma ionized calcium above the median. We found no interactions between plasma ionized calcium and preexisting cardiovascular or renal disease on all-cause mortality.

CONCLUSION

In the general population, low plasma ionized calcium was associated with increased all-cause, cancer, and other mortality, while high levels were associated with increased cardiovascular mortality.

Imaging features of hypercalcemia: A primer for emergency radiologists

Hypercalcemia is a marker for a wide variety of underlying etiologies, and its presentation in the emergency setting may be asymptomatic, incidental, or a primary complaint with associated symptoms and physical exam findings. While the workup is initially driven through serum laboratory testing, imaging plays an important role in diagnosis and post-treatment follow up. This review covers multiple common and uncommon etiologies of hypercalcemia, details their underlying mechanisms, and identifies the most important associated imaging findings. It is important for radiologists to be familiar with these etiologies and imaging findings, particularly in the emergency setting since hypercalcemia may represent the only significant laboratory abnormality associated with the presenting condition. Furthermore, the radiologist's interpretation of a study may be directly influenced by knowing about a patient's hypercalcemia.

Admission Serum Ionized and Total Calcium as New Predictors of Mortality in Patients with Cardiogenic Shock

Background

Although serum calcium has been proven to be a predictor of mortality in a wide range of diseases, its prognostic value in critically ill patients with cardiogenic shock (CS) remains unknown. This retrospective observational study is aimed at investigating the association of admission calcium with mortality among CS patients.

Methods

Critically ill patients diagnosed with CS in the Medical Information Mart for Intensive Care-III (MIMIC-III) database were included in our study. The study endpoints included 30-day, 90-day, and 365-day all-cause mortalities. First, admission serum ionized calcium (iCa) and total calcium (tCa) levels were analyzed as continuous variables using restricted cubic spline Cox regression models to evaluate the possible nonlinear relationship between serum calcium and mortality. Second, patients with CS were assigned to four groups according to the quartiles (Q1-Q4) of serum iCa and tCa levels, respectively. In addition, multivariable Cox regression analyses were used to assess the independent association of the quartiles of iCa and tCa with clinical outcomes.

Results

A total of 921 patients hospitalized with CS were enrolled in this study. A nonlinear relationship between serum calcium levels and 30-day mortality was observed (all P values for nonlinear trend < 0.001). Furthermore, multivariable Cox analysis showed that compared with the reference quartile (Q3: 1.11 ≤ iCa < 1.17 mmol/L), the lowest serum iCa level quartile (Q1: iCa < 1.04 mmol/L) was independently associated with an increased risk of 30-day mortality (Q1 vs. Q3: HR 1.35, 95% CI 1.00-1.83, P = 0.049), 90-day mortality (Q1 vs. Q3: HR 1.36, 95% CI 1.03-1.80, P = 0.030), and 365-day mortality (Q1 vs. Q3: HR 1.28, 95% CI 1.01-1.67, P = 0.046) in patients with CS.

Conclusions

Lower serum iCa levels on admission were potential predictors of an increased risk of mortality in critically ill patients with CS.

Tetany Exacerbating Heart Failure: A Case Report

Tetany is characterized by numbness and stiffness in the hands and feet caused by hypocalcemia, hypomagnesemia, and hyperventilatory alkalosis, primarily at peripheral neuromuscular junctions. Although hypocalcemia is common in critically ill patients, its diagnosis of hypocalcemia is complicated and sometimes overlooked. We encountered an 82-year-old woman with tetany that exacerbated heart failure. Pain and respiratory failure due to tetany are conditions that can lead to exacerbation of heart failure. Chronic renal failure is frequently associated with chronic heart failure, and regular follow-up of calcium, phosphorus, and magnesium levels is necessary for such patients.

Electrolyte and acid-base disorders in cancer patients and its impact on clinical outcomes: evidence from a real-world study in China

Background: This study aims to delineate the incidence of electrolyte and acid-base disorders (EAD) in cancer patients, to figure out the risk factors of EAD, then to assess the impact of EAD on patients' in-hospital clinical outcomes.Methods: Patients with the diagnosis of malignancies hospitalized during 1 October 2014 and 30 September 2015 were recruited in Zhongshan Hospital, Fudan University in Shanghai of China. Demographic characteristics, comorbidities, and clinical data, including survival, length of stay and hospital cost, were extracted from the electronic medical record system. Electrolyte and acid-base data were acquired from the hospital laboratory database.Results: Of 25,881 cancer patients with electrolyte data, 15,000 (58.0%) cases had at least one electrolyte and acid-base abnormity. Hypocalcemia (27.8%) was the most common electrolyte disorder, followed by hypophosphatemia (26.7%), hypochloremia (24.5%) and hyponatremia (22.5%). The incidence of simple metabolic acidosis (MAC) and metabolic alkalosis (MAL) was 12.8% and 22.1% respectively. Patients with mixed metabolic acid-base disorders (MAC + MAL) accounted for 30.2%. Lower BMI score, preexisting hypertension and diabetes, renal dysfunction, receiving surgery/chemotherapy, anemia and hypoalbuminemia were screened out as the major risk factors of EAD. In-hospital mortality in patients with EAD was 2.1% as compared to those with normal electrolytes (0.3%). The risk of death significantly increased among patients with severe EAD. Similarly, the length of stay and hospital cost also tripled as the number and grade of EAD increased.Conclusion: EAD is commonly encountered in cancer patients and associated with an ominous prognosis. Patients with comorbidities, renal/liver dysfunction, and anti-tumor therapy have a higher risk of EAD. Regular monitoring of electrolytes, optimum regimen for intravenous infusion, timely correction of modifiable factors and appropriate management of EAD should not be neglected during anti-tumor treatment.

Hospital-Acquired Serum Ionized Calcium Derangements and Their Associations with In-Hospital Mortality

Background: The objective of this study was to report the incidence of in-hospital serum ionized calcium derangement and its impact on mortality. Methods: We included 12,599 non-dialytic adult patients hospitalized at a tertiary medical center from January 2009 to December 2013 with normal serum ionized calcium at admission and at least 2 in-hospital serum ionized calcium values. Using serum ionized calcium of 4.60–5.40 mg/dL as the normal reference range, in-hospital serum ionized calcium levels were categorized based on the presence of hypocalcemia and hypercalcemia in hospital. We performed logistic regression to assess the relationship of in-hospital serum ionized calcium derangement with mortality. Results: Fifty-four percent of patients developed new serum ionized calcium derangements: 42% had in-hospital hypocalcemia only, 4% had in-hospital hypercalcemia only, and 8% had both in-hospital hypocalcemia and hypercalcemia. In-hospital hypocalcemia only (OR 1.28; 95% CI 1.01–1.64), in-hospital hypercalcemia only (OR 1.64; 95% CI 1.02–2.68), and both in-hospital hypocalcemia and hypercalcemia (OR 1.73; 95% CI 1.14–2.62) were all significantly associated with increased in-hospital mortality, compared with persistently normal serum ionized calcium levels. Conclusions: In-hospital serum ionized calcium derangements affect more than half of hospitalized patients and are associated with increased in-hospital mortality.

Calcium state estimation by total calcium: the evidence to end the never-ending story

Background Total blood calcium (TCa) is routinely used to diagnose and manage mineral and bone metabolism disorders. Numerous laboratories adjust TCa by albumin, though literature suggests there are some limits to this approach. Here we report a large retrospective study on agreement rate between ionized calcium (iCa) measurement and TCa or albumin-adjusted calcium measurements. Methods We retrospectively selected 5055 samples with simultaneous measurements of iCa, TCa, albumin and pH. We subgrouped our patients according to their estimated glomerular filtration rate (eGFR), albumin levels and pH. We analyzed each patient's calcium state with iCa as reference to determine agreement rate with TCa and albumin-adjusted calcium using Payne, Clase, Jain and Ridefelt formulas. Results The Payne formula performed poorly in patients with abnormal albumin, eGFR or pH levels. In patients with low albumin levels or blood pH disorders, Payne-adjusted calcium may overestimate the calcium state in up to 80% of cases. Similarly, TCa has better agreement with iCa in the case of hypoalbuminemia, but performed similarly to the Payne formula in patients with physiological albumin levels. The global agreement rate for Clase, Jain and Ridefelt formulas suggests significant improvement compared to Payne calcium adjustment but no significant improvement compared to TCa. Conclusions Total and albumin-adjusted calcium measurement leads to a misclassification of calcium status. Moreover, accurate calcium state determination depends on blood pH levels, whose measurement requires the same pre-analytical restrictions as iCa measurement. We propose that iCa should instead become the reference method to determine the real calcium state.

Epidemiology, clinical features, and management of severe hypercalcemia in critically ill patients

BACKGROUND

Severe hypercalcemia (HCM) is a common reason for admission in intensive-care unit (ICU). This case series aims to describe the clinical and biological features, etiologies, treatments, and outcome associated with severe HCM. This study included all patients with a total calcemia above 12 mg/dL (3 mmol/L) admitted in two ICUs from January 2007 to February 2017.

RESULTS

131 patients with HCM were included. HCM was related to hematologic malignancy in 58 (44.3%), solid tumors in 29 (22.1%), endocrinopathies in 16 (12.2%), and other causes in 28 (21.3%) patients. 108 (82.4%) patients fulfilled acute kidney injury (AKI) criteria. Among them, 25 (19%) patients required renal replacement therapy (RRT). 51 (38.9%) patients presented with neurological symptoms, 73 (55.7%) patients had cardiovascular manifestations, and 50 (38.1%) patients had digestive manifestations. The use of bisphosphonates (HR, 0.42; 95% CI, 0.27-0.67; P < 0.001) was the only treatment significantly associated with a decrease of total calcemia below 12 mg/dL (3 mmol/L) at day 5. ICU and Hospital mortality rates were, respectively, 9.9% and 21.3%. Simplified Acute Physiologic Score (SAPS II) (OR, 1.05; 95% CI 1.01-1.1; P = 0.03) and an underlying solid tumor (OR, 13.83; 95% CI 2.24-141.25; P = 0.01) were two independent factors associated with hospital mortality in multivariate analysis.

CONCLUSIONS

HCM is associated with high mortality rates, mainly due to underlying malignancies. The course of HCM may be complicated by organ failures which are most of the time reversible with early ICU management. Early ICU admission and prompt HCM management are crucial, especially in patients with an underlying solid tumor presenting with neurological symptoms.

Electrolyte imbalances in an unselected population in an emergency department: A retrospective cohort study

BACKGROUND

Although electrolyte imbalances (EIs) are common in the emergency department (ED), few studies have examined the occurrence of such conditions in an unselected population.

OBJECTIVES

To investigate the frequency of EI among adult patients who present to the ED, with regards to type and severity, and the association with age and sex of the patient, hospital length of stay (LOS), readmission, and mortality.

METHODS

A retrospective cohort study. All patients ≥18 years referred for any reason to the ED between January 1, 2010, and December 31, 2015, who had measured blood electrolytes were included. In total, 62 991 visits involving 31 966 patients were registered.

RESULTS

EIs were mostly mild, and the most common EI was hyponatremia (glucose-corrected) (24.6%). Patients with increasing severity of EI had longer LOS compared with patients with normal electrolyte measurements. Among all admitted patients, there were 12928 (20.5%) readmissions within 30 days from discharge during the study period. Hyponatremia (glucose-corrected) was associated with readmission, with an adjusted odds ratio (OR) of 1.25 (95% CI, 1.18-1.32). Hypomagnesemia and hypocalcemia (albumin-corrected) were also associated with readmission, with ORs of 1.25 (95% CI, 1.07-1.45) and 1.22 (95% CI, 1.02-1.46), respectively. Dysnatremia, dyskalemia, hypercalcemia, hypermagnesemia, and hyperphosphatemia were associated with increased in-hospital mortality, whereas all EIs except hypophosphatemia were associated with increased 30-day and 1-year mortality.

CONCLUSIONS

EIs were common and increasing severity of EIs was associated with longer LOS and increased in-hospital, 30-days and 1-year mortality. EI monitoring is crucial for newly admitted patients, and up-to-date training in EI diagnosis and treatment is essential for ED physicians.

HYPOCALCEMIC CARDIOMYOPATHY - A RARE HEART FAILURE ETIOLOGY IN ADULT

INTRODUCTION

Heart failure and dilated cardiomyopathy (DCM) in adults are rarely caused by hypoparathyroidism induced hypocalcemia.

CASE REPORT

Female patient, 40 years old, diabetic, with previous history of thyroidectomy for Graves' disease, was hospitalized for syncope and symptoms of heart failure. ECG revealed sinus tachycardia, long QT, negative T from V1 up to V4. Chest X-ray, cardiac ultrasound and contrast cardiac MRI confirmed dilated left chambers, severe systolic dysfunction of the left ventricle (left ventricle ejection fraction=15%) due to diffuse hypokinesia and restrictive type of diastolic dysfunction. Patient status insignificantly improved with specific heart failure depletion treatment but important signs of hypocalcemia occurred. Low levels of total and ionic serum calcium were detected (total serum calcium 3.6 mg/dL, ionic calcium=2.2 mg/dL) along with low serum levels of parathormone (10 pg/mL) and high level of phosphatemia (6.4 mg/dL). After one month of parenteral treatment with calcium and oral vitamin D, hypocalcemic signs disappeared and heart failure significantly improved.

CONCLUSION

This rare adult condition is refractory to heart failure conventional therapy but promptly responds to restoration of normocalcemia. It is important to be aware of this pathophysiological setting, in order to treat it correctly.

Is severe hypocalcemia immediately life-threatening?

Objective

Severe hypocalcemia (Ca <1.9 mmol/L) is often considered an emergency because of a potential risk of cardiac arrest or seizures. However, there is little evidence to support this. The aim of our study was to assess whether severe hypocalcemia was associated with immediately life-threatening cardiac arrhythmias or neurological complications.

Methods

A retrospective observational study was carried out over a 2 years period in the Adult Emergency Department (ED) of Nantes University Hospital. All patients who had a protein-corrected calcium concentration measure were eligible for inclusion. Patients with multiple myeloma were excluded. The primary outcome was the number of life-threatening cardiac arrhythmias and/or neurological complications during the stay in the ED.

Results

A total of 41,823 patients had protein-corrected calcium (pcCa) concentrations measured, 155 had severe hypocalcaemia, 22 were excluded because of myeloma leaving 133 for analysis. Median pcCa concentration was 1.73 mmol/L [1.57-1.84]. Seventeen (12.8%) patients presented a life threatening condition, 14 (10.5%) neurological and 3 (2.2%) cardiac during ED stay. However these complications could be explained by the presence of underlying co-morbidities and or electrolyte disturbances other than hypocalcaemia. Overall 24 (18%) patients died in hospital. Vitamin D deficiency, chronic kidney disease and hypoparathyroidism were the most frequently found causes of hypocalcemia.

Conclusion

13% of patients with severe hypocalcaemia presented a life-threatening cardiac or neurological complication on the ED. However a perfectly valid alternative cause could account for these complications. Further research is warranted to define the precise role of hypocalcaemia.

Impact of admission serum calcium levels on mortality in hospitalized patients

OBJECTIVES

To assess the relationship between admission serum calcium levels and in-hospital mortality in all hospitalized patients.

METHODS

All adult hospitalized patients who had admission serum calcium levels available between years 2009 and 2013 were enrolled. Admission serum calcium was categorized based on its distribution into six groups (<7.9, 7.9 to <8.4, 8.4 to <9.0, 9.0 to <9.6, 9.6 to <10.1, and ≥10.1 mg/dL). The odds ratio (OR) of in-hospital mortality by admission serum calcium, using the calcium category of 9.6-10.1 mg/dL as the reference group, was obtained by logistic regression analysis.

RESULTS

18,437 patients were studied. The lowest incidence of in-hospital mortality was associated with admission serum calcium within 9.6 to <10.1 mg/dL. A higher in-hospital mortality rate was observed in patients with serum calcium <9.6 and ≥10.1 mg/dL. Also, 38% and 33% of patients with admission serum calcium <7.9 and ≥10.1 mg/dL were on calcium supplements before admission, respectively. After adjusting for potential confounders, both serum calcium <8.4 and ≥10.1 mg/dL were associated with an increased risk of in-hospital mortality with ORs of 2.86 [95% confidence interval (CI) 1.98-4.17], 1.74 (95% CI 1.21-2.53), and 1.69 (95% CI 1.10-2.59) when serum calcium were within <7.9, 7.9 to <8.4, and ≥10.1 mg/dL, respectively.

CONCLUSION

Hypocalcemia and hypercalcemia on admission were associated with in-hospital mortality. Highest mortality risk is observed in patients with admission hypocalcemia (<7.9 mg/dL). One-third of patients with hypercalcemia on admission were on calcium supplements.

Associations between serum calcium, phosphorus and mortality among patients with coronary heart disease

PURPOSE

Serum calcium and phosphorus abnormalities are associated with cardiovascular disorders in general population, but evidence among patients with established coronary heart disease (CHD) is limited and controversial. This study aimed to investigate the associations of baseline serum calcium and phosphorus levels with long-term mortality risk among patients with CHD.

METHODS

We conducted a prospective cohort study among 3187 patients with CHD from October 2008 and December 2011 in China. Cox proportional hazards model was used to assess the associations of serum calcium and phosphorus at baseline with the risk of death.

RESULTS

During follow-up (mean, 4.9 years), 295 patients died, 193 of which resulted from cardiovascular causes. Multivariable-adjusted hazard ratios (HR) for each 1 mmol/L increase in serum calcium at baseline were 0.27 (95% confidence interval (CI) 0.14-0.51) for all-cause mortality and 0.26 (95% CI 0.12-0.54) for cardiovascular mortality. Patients in the highest compared to the lowest quartile of serum calcium were at lower risk of all-cause mortality (HR, 95% CI 0.57, 0.40-0.82) and cardiovascular mortality (0.50, 0.32-0.79) (both P _trend < 0.001). This inverse association between serum calcium and the risk of mortality did not change when participants were stratified by sex, age groups, level of overweight, types of CHD, and history of diabetes. We also observed a graded positive association between baseline serum phosphorus and the risks of mortality.

CONCLUSIONS

The present study is the first to report that lower serum calcium at baseline is associated with an increased risk of all-cause and cardiovascular mortality in a Chinese coronary heart disease cohort. Further studies are required to investigate the causal relationship and actual mechanisms.

Calcium levels on admission and before discharge are associated with mortality risk in hospitalized patients

AIM

Investigate the association of calcium levels on admission and change in levels during hospitalization with hospitalization outcomes.

METHODS

Historical prospective data of patients hospitalized to units of internal medicine between 2011 and 2013. Albumin-corrected-calcium levels were classified to marked hypocalcemia (<7.5 mg/dL), mild hypocalcemia (7.5-8.5 mg/dL), normal calcium (8.5-10.5 mg/dL), mild hypercalcemia (10.5-11.5 mg/dL), marked hypercalcemia (>11.5 mg/dL). Main outcomes were length-of-hospitalization, in-hospital and long-term mortality.

RESULTS

Cohort included 30,813 patients (mean age 67 ± 18 years, 51% male). Follow-up (median ± standard deviation) was 1668 ± 325 days. Most patients had normal calcium on admission (93%), 3% had hypocalcemia, 3% had hypercalcemia. Common causes for marked hypercalcemia were malignancy (56%) and hyperparathyroidism (22%). Last calcium levels before discharge or death were normal in 94%, with similar rates of hypercalcemia or hypocalcemia (3% each). Compared to in-hospital mortality with normal calcium on admission (6%), mortality was higher with mild (8%) and marked hypocalcemia (11%), and highest with mild (18%) and marked hypercalcemia (22%). Mortality rate at the end of follow-up was 48% with normal calcium or mild hypocalcemia, 51% with marked hypocalcemia, 68 and 79% with mild and marked hypercalcemia, respectively. Patients with normal calcium on admission and before discharge had the best prognosis. Hypercalcemia on admission or before discharge was associated with a 70% mortality risk at the end of follow-up. Normalization of admission hypercalcemia had no effect on long-term mortality risk.

CONCLUSIONS

Abnormal calcium on admission is associated with increased short-term and long-term mortality. The excess mortality risk is higher with hypercalcemia than hypocalcemia. Calcium normalization before discharge had no effect on mortality.

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.