Impact of low serum calcium at hospital admission on SARS-CoV-2 infection outcome

Calcium, phosphorus, magnesium levels in frequent respiratory tract infections

BACKGROUND

It was well documented that calcium (Ca), phosphorus (P), and magnesium (Mg) participate in many physiological processes. We aimed to study the changing trend of serum levels of Ca, P, and Mg in frequent respiratory tract infections (FRTI) in children.

METHODS

A retrospective study was performed in our centre. A total of 213 FRTI cases and 33 controls were enrolled in our study. We analyzed the correlation between serum Ca/P/Mg levels and inflammatory indexes by using Spearman correlation analysis. Standard mean difference (SMD) was applied to test the differences of serum Ca/P/Mg levels between FRTI subgroups and controls. In terms of the findings of SMD between Ca/P/Mg status between FRTI subgroups and controls, receiver operating characteristics (ROC) curve analysis was further applied to test the association between serum Ca level and bronchitis, parainfluenza virus infection, influenza B virus infection and cytomegalovirus infection.

RESULTS

Serum Ca level was significantly associated with white blood cell (WBC), platelet (PLT) and procalcitonin (PCT) (p = 0.006; p < 10-4; p = 0.004). Serum P level was markedly associated with eryhtrocyte sedimentation rate (ESR) and PCT (p = 0.018; p < 10-4). Controls showed significantly lower serum Ca level than that among bronchitis (p = 0.001), parainfluenza virus infection (p = 0.027), influenza B virus infection (p = 0.017), cytomegalovirus infection (p = 0.029), and two pathogens infected (p = 0.020). ROC curve analysis showed that serum Ca level was significantly associated with bronchitis (p = 0.047) and influenza B virus infection (p = 0.049).

CONCLUSIONS

Serum levels of Ca and P may reflect the inflammatory status in children with FRTI. Alteration of serum Ca level may predict the risk of bronchitis and influenza B virus infection. Keeping the homeostasis of Ca, P, and Mg may be important for the prevention and treatment of FRTI.

Regional and Age-Related Variations in Blood Calcium Levels among Patients with Plasmodium falciparum and P. vivax malaria: A Systematic Review and Meta-Analysis

Despite several studies examining the relationship between calcium levels and malaria, inconsistencies and varied results remain in the literature. This study aimed to synthesize the evidence on the association between blood calcium levels and malaria severity. A systematic literature search was conducted in the Embase, Scopus, PubMed, Ovid, and Google Scholar databases. The studies that investigated calcium levels in participants with malaria were reviewed and included for synthesis. The quality of included studies was assessed based on a standardized checklist by the Joanna Briggs Institute (JBI) critical appraisal checklists. The thematic synthesis had been used for qualitative synthesis. For the quantitative synthesis, the meta-analysis was performed to estimate the pooled effect sizes for differences in calcium levels between groups of participants using a random effect model using Hedge's g as a measure of effect size. Out of the 4574 identified records, 14 studies were reviewed. The thematic synthesis across these studies noted a consistent theme: reduced calcium levels in malaria patients compared to uninfected controls. However, the meta-analysis encompassing three specific analyses-comparing calcium levels between malaria patients and controls, severe and non-severe malaria cases, and fatal cases versus survivors-showed no significant difference in calcium levels. The statistics were as follows: (1) p = 0.15, Hedge's g: -1.00, 95% CI: -2.37-0.38, I2: 98.97, 9 studies; (2) p = 0.35, Hedge's g: -0.33, 95% CI: -1.02-0.36, I2: 81.61, 3 studies; and (3) p = 0.71, Hedge's g: -0.14, 95% CI: -0.91-0.62, I2: 87.05, 3 studies. Subgroup analyses indicated that regional disparities, especially between Africa and Asia, and participant age groups may influence these outcomes. While a trend of decreased calcium levels in malaria patients was observed, the meta-analytical results suggest regional and age-related variations. Further investigations should emphasize these differences to better guide clinical management, prognostic applications, and the crafting of policies concerning malaria's metabolic effects.

Total network controllability analysis discovers explainable drugs for Covid-19 treatment

BACKGROUND

The active pursuit of network medicine for drug repurposing, particularly for combating Covid-19, has stimulated interest in the concept of structural controllability in cellular networks. We sought to extend this theory, focusing on the defense rather than control of the cell against viral infections. Accordingly, we extended structural controllability to total structural controllability and introduced the concept of control hubs. Perturbing any control hub may render the cell uncontrollable by exogenous stimuli like viral infections, so control hubs are ideal drug targets.

RESULTS

We developed an efficient algorithm to identify all control hubs, applying it to a largest homogeneous network of human protein interactions, including interactions between human and SARS-CoV-2 proteins. Our method recognized 65 druggable control hubs with enriched antiviral functions. Utilizing these hubs, we categorized potential drugs into four groups: antiviral and anti-inflammatory agents, drugs acting on the central nervous system, dietary supplements, and compounds enhancing immunity. An exemplification of our approach's effectiveness, Fostamatinib, a drug initially developed for chronic immune thrombocytopenia, is now in clinical trials for treating Covid-19. Preclinical trial data demonstrated that Fostamatinib could reduce mortality rates, ICU stay length, and disease severity in Covid-19 patients.

CONCLUSIONS

Our findings confirm the efficacy of our novel strategy that leverages control hubs as drug targets. This approach provides insights into the molecular mechanisms of potential therapeutics for Covid-19, making it a valuable tool for interpretable drug discovery. Our new approach is general and applicable to repurposing drugs for other diseases.

Potential impacts of SARS-CoV-2 on parathyroid: current advances and trends

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection affects several important organs including endocrine glands. Experimental studies demonstrated that the virus exploits the ACE2, a transmembrane glycoprotein on the cell surface as a receptor for cellular entry. This entry process is exclusively facilitated by other intracellular protein molecules such as TMPRSS2, furin, NRP1, and NRP2. Recent findings documented the involvement of the SARS-CoV-2 in inducing various parathyroid disorders including hypoparathyroidism and hypocalcemia, which received significant attention. This review extensively describes rapidly evolving knowledge on the potential part of SARS-CoV-2 in emerging various parathyroid disorders due to SARS-CoV-2 infection particularly parathyroid malfunction in COVID-19 cases, and post-COVID-19 conditions. Further, it presents the expression level of various molecules such as ACE2, TMPRSS2, furin, NRP1, and NRP2 in the parathyroid cells that facilitate the SARS-CoV-2 entry into the cell, and discusses the possible mechanism of parathyroid gland infection. Besides, it explores parathyroid malfunction in COVID-19 vaccine-administered cases. It also explains the possible long-COVID-19 effect on parathyroid and post-COVID-19 management of parathyroid. A complete understanding of the mechanisms of SARS-CoV-2-triggered pathogenesis in parathyroid dysfunctions may curtail treatment options and aid in the management of SARS-CoV-2-infected cases.

Calcium, Phosphorus and Magnesium Abnormalities Associated with COVID-19 Infection, and Beyond

The coronavirus disease (COVID-19) pandemic caused by the novel coronavirus SARS-CoV-2 has had a profound impact on global health, leading to a surge in research to better understand the pathophysiology of the disease. Among the various aspects under investigation, disruptions in mineral homeostasis have emerged as a critical area of interest. This review aims to provide an overview of the current evidence linking calcium, phosphorus and magnesium abnormalities with COVID-19 infection and explores the potential implications beyond the acute phase of the disease. Beyond the acute phase of COVID-19, evidence suggests a potential impact of these mineral abnormalities on long-term health outcomes. Persistent alterations in calcium, phosphorus and magnesium levels have been linked to increased cardiovascular risk, skeletal complications and metabolic disorders, warranting continuous monitoring and management in post-COVID-19 patients.

Hypocalcemia on Admission Is a Predictor of Disease Progression in COVID-19 Patients with Cirrhosis: A Multicenter Study in Hungary

Hypocalcemia is a common condition in liver cirrhosis and is associated with the severity of SARS-CoV-2 infection. However, there is a lack of data demonstrating the prognostic value of hypocalcemia in COVID-19 patients with cirrhosis. This study aimed to evaluate the prognostic value of hypocalcemia for COVID-19 severity, mortality and its associations with abnormal liver function parameters. We selected 451 COVID-19 patients in this retrospective study and compared the laboratory findings of 52 COVID-19 patients with cirrhosis to those of 399 COVID-19 patients without cirrhosis. Laboratory tests measuring albumin-corrected total serum calcium were performed on admission, and the levels were monitored during hospitalization. The total serum calcium levels were significantly lower in cirrhosis cases (2.16 mmol/L) compared to those without cirrhosis (2.32 mmol/L). Multivariate analysis showed that hypocalcemia in COVID-19 patients with cirrhosis was a significant predictor of in-hospital mortality, with an OR of 4.871 (p < 0.05; 95% CI 1.566-15.146). ROC analysis showed the AUC value of total serum calcium was 0.818 (95% CI 0.683-0.953, p < 0.05), with a sensitivity of 88.3% and a specificity of 75%. The total serum calcium levels showed a significant negative correlation with the Child-Turcette-Pugh score (r = -0.400, p < 0.05). Hypocalcemia on admission was a significant prognostic factor of disease progression in COVID-19 patients with cirrhosis.

Additive prognostic value of serum calcium to the ESC risk stratification in patients with acute pulmonary embolism

BACKGROUND

Hypocalcemia has been shown to be involved in the adverse outcomes of acute pulmonary embolism (APE). We aimed to determine the incremental value of adding hypocalcemia, defined as serum calcium level ≤ 2.12 mmol/L, on top of the European Society of Cardiology (ESC) prognostic algorithm, for the prediction of in-hospital mortality in APE patients, which in turn could lead to the optimization of APE management.

METHODS

This study was conducted at West China Hospital of Sichuan University from January 2016 to December 2019. Patients with APE were retrospectively analyzed and divided into 2 groups based on serum calcium levels. Associations between hypocalcemia and adverse outcomes were assessed by Cox analysis. The accuracy of risk stratification for in-hospital mortality was assessed with the addition of serum calcium to the current ESC prognostic algorithm.

RESULTS

Among 803 patients diagnosed with APE, 338 (42.1%) patients had serum calcium levels ≤ 2.12 mmol/L. Hypocalcemia was significantly associated with higher in-hospital and 2-year all-cause mortality compared to the control group. The addition of serum calcium to ESC risk stratification enhanced net reclassification improvement. Low-risk group with serum calcium level > 2.12 mmol/L had a 0% mortality rate, improving the negative predictive value up to 100%, while high-risk group with serum calcium level ≤ 2.12 mmol/L indicated a higher mortality of 25%.

CONCLUSION

Our study identified serum calcium as a novel predictor of mortality in patients with APE. In the future, serum calcium may be added to the commonly used ESC prognostic algorithm for better risk stratification of patients suffering from APE.

Electrolyte imbalances as poor prognostic markers in COVID-19: a systemic review and meta-analysis

PURPOSE

Serum electrolyte imbalances are highly prevalent in COVID-19 patients. However, their associations with COVID-19 outcomes are inconsistent, and of unknown prognostic value. We aim to systematically clarify the associations and prognostic accuracy of electrolyte imbalances (sodium, calcium, potassium, magnesium, chloride and phosphate) in predicting poor COVID-19 clinical outcome.

METHODS

PubMed, Embase and Cochrane Library were searched. Odds of poor clinical outcome (a composite of mortality, intensive-care unit (ICU) admission, need for respiratory support and acute respiratory distress syndrome) were pooled using mixed-effects models. The associated prognostic sensitivity, positive and negative likelihood ratios (LR + , LR-) and predictive values (PPV, NPV; assuming 25% pre-test probability), and area under the curve (AUC) were computed.

RESULTS

We included 28 observational studies from 953 records with low to moderate risk-of-bias. Hyponatremia (OR = 2.08, 95% CI = 1.48-2.94, I² = 93%, N = 8), hypernatremia (OR = 4.32, 95% CI = 3.17-5.88, I² = 45%, N = 7) and hypocalcemia (OR = 3.31, 95% CI = 2.24-4.88, I² = 25%, N = 6) were associated with poor COVID-19 outcome. These associations remained significant on adjustment for covariates such as demographics and comorbidities. Hypernatremia was 97% specific in predicting poor outcome (LR + 4.0, PPV = 55%, AUC = 0.80) despite no differences in CRP and IL-6 levels between hypernatremic and normonatremic patients. Hypocalcemia was 76% sensitive in predicting poor outcome (LR- 0.44, NPV = 87%, AUC = 0.71). Overall quality of evidence ranged from very low to moderate.

CONCLUSION

Hyponatremia, hypernatremia and hypocalcemia are associated with poor COVID-19 clinical outcome. Hypernatremia is 97% specific for a poor outcome, and the association is independent of inflammatory marker levels. Further studies should evaluate if correcting these imbalances help improve clinical outcome.

An overview on role of nutrition on COVID-19 immunity: Accumulative review from available studies

The novel coronavirus infection (COVID-19) conveys a serious global threat to health and economy. A common predisposing factor for development to serious progressive disease is presence of a low-grade inflammation, e.g., as seen in diabetes, metabolic syndrome, and heart failure. Micronutrient deficiencies may also contribute to the development of this state. Therefore, the aim of the present study is to explore the role of the nutrition to relieve progression of COVID-19. According PRISMA protocol, we conducted an online databases search including Scopus, PubMed, Google Scholar and web of science for published literatures in the era of COVID-19 Outbreak regarding to the status of nutrition and COVID-19 until December 2021. There were available studies (80 studies) providing direct evidence regarding the associations between the status of nutrition and COVID-19 infection. Adequate nutritional supply is essential for resistance against other viral infections and also for improvement of immune function and reduction of inflammation. Hence, it is suggested that nutritional intervention which secures an adequate status might protect against the novel coronavirus SARS-CoV-2 (Severe Acute Respiratory Syndrome - coronavirus-2) and mitigate its course. We also recommend initiation of adequate nutritional supplementation in high-risk areas and/or soon after the time of suspected infection with SARS-CoV-2. Subjects in high-risk groups should have high priority for applying this nutritive adjuvant therapy that should be started prior to administration of specific and supportive medical measures.

Serum Calcium, Magnesium, and Phosphorus Levels in Patients with COVID-19: Relationships with Poor Outcome and Mortality

In this retrospective study to assess the impact of serum corrected calcium (CorrCa), magnesium (Mg) and phosphorus (P) levels, all adult patients with laboratory-confirmed COVID-19 hospitalized during 2020 were included. Poor outcome was considered in patients who presented need for mechanical ventilation, intensive care unit (ICU) admission, or in-hospital mortality. We analyzed 2473 patients (956 females) aged (mean±SD) 63.4±15.9 years. During admission, 169 patients (6.8%) required mechanical ventilation, 205 (8.3%) were admitted to the ICU, and 270 (10.9%) died. Composite variable of poor outcome, defined as need for mechanical ventilation, ICU admission or death, was present in 434 (17.5%) patients. In univariate analysis, the need for mechanical ventilation was positively related to Mg levels (OR 8.37, 95% CI 3.62-19.33; p<0.001); ICU admission was related to CorrCa (OR 0.49, 95% CI 0.25-0.99; p=0.049) and Mg levels (OR 5.81, 95% CI 2.74-12.35; p<0.001); and in-hospital mortality was related to CorrCa (OR 1.73, 95% CI 1.14-2.64; p=0.011). The composite variable of poor outcome was only related to Mg (OR 2.68, 95% CI 1.54-4.68; p=0.001). However, in multivariate analysis only CorrCa was significantly related to the need for mechanical ventilation (OR 0.19, 95% CI 0.05-0.72; p=0.014) and ICU admission (OR 0.25; 95% CI 0.09-0.66; p=0.005), but not with in-hospital mortality or the composite variable. In conclusion, CorrCa can be used as a simple and reliable marker of poor outcome in patients with COVID-19, although not to predict the risk of in-hospital mortality.

The calcium-sensing receptor in inflammation: Recent updates

The Calcium-Sensing Receptor (CaSR) is a member of the class C of G-proteins coupled receptors (GPCRs), it plays a pivotal role in calcium homeostasis by directly controlling calcium excretion in the kidneys and indirectly by regulating parathyroid hormone (PTH) release from the parathyroid glands. The CaSR is found to be ubiquitously expressed in the body, playing a plethora of additional functions spanning from fluid secretion, insulin release, neuronal development, vessel tone to cell proliferation and apoptosis, to name but a few. The present review aims to elucidate and clarify the emerging regulatory effects that the CaSR plays in inflammation in several tissues, where it mostly promotes pro-inflammatory responses, with the exception of the large intestine, where contradictory roles have been recently reported. The CaSR has been found to be expressed even in immune cells, where it stimulates immune response and chemokinesis. On the other hand, CaSR expression seems to be boosted under inflammatory stimulus, in particular, by pro-inflammatory cytokines. Because of this, the CaSR has been addressed as a key factor responsible for hypocalcemia and low levels of PTH that are commonly found in critically ill patients under sepsis or after burn injury. Moreover, the CaSR has been found to be implicated in autoimmune-hypoparathyroidism, recently found also in patients treated with immune-checkpoint inhibitors. Given the tight bound between the CaSR, calcium and vitamin D metabolism, we also speculate about their roles in the pathogenesis of severe acute respiratory syndrome coronavirus-19 (SARS-COVID-19) infection and their impact on patients' prognosis. We will further explore the therapeutic potential of pharmacological targeting of the CaSR for the treatment and management of aberrant inflammatory responses.

Evaluation of the correlation of serum calcium, phosphorus levels and calcium phosphorus product with disease severity and ICU mortality in SARS-COV-2 pneumonia patients followed up in ICU

Background: Calcium and phosphorus are important elements in the body that have been shown to decrease in critical inflammatory diseases. The aim of this study was to evaluate serum levels of calcium and phosphorus and the calcium phosphate product (CPP) in patients followed up in intensive care unit (ICU) due to hypoxemic respiratory failure caused by coronavirus disease 2019 (COVID-19) pneumonia. The secondary endpoint of the study were respiratory support therapies used in the evaluation of independent mortality and disease severity in ICU that were divided into four groups depending on the time of administration: (i) first 24 hours, (ii) 48-72 hours, (iii) 72 hours, and (iv) 72 hours-28 days. Material and Method: The retrospective study included patients with critical and severe COVID-19 pneumonia followed up in ICU. Results: The study included 369 patients with a mean age of 64.3±14.8 years. ICU mortality was observed in 142 (38.5%) patients, among whom 17 (4.6%) patients died within 24 hours, 28 (7.6%) died between 48-72 hours, 50 (12.7%) died within 72 hours, and 47 (12.7%) died between 72 hours and 28 days. Serum calcium level established a significant relationship with ICU mortality at 28 days and 72 hours (p0.05). Conclusion: Serial assessment of serum calcium may be a new criterion in the prediction of independent mortality in critical and severe COVID-19 pneumonia, which has been recently identified and has numerous unknown features.

Effects of nutrients on immunomodulation in patients with severe COVID-19: Current knowledge

Recent research has demonstrated that critically ill patients with coronavirus disease 2019 (COVID-19) show significant immune system dysregulation. Due to that, some nutrients that influence immunomodulation have been suggested as a form of treatment against the infection. This review collected the information on the impact of vitamins on the prognosis of COVID-19, with the intention of facilitating treatment and prevention of the disease risk status in patients. The collected information was obtained using the PubMed electronic database by searching for articles that relate COVID-19 and the mechanisms/effects of the nutrients: Proteins, glucose, lipids, vitamin B12, vitamin D, calcium, iron, copper, zinc, and magnesium, including prospective, retrospective, and support articles. The findings reveal an optimal response related mainly to omega-3, eicosapentaenoic acid, docosahexaenoic acid, calcium, and iron that might represent benefits in the treatment of critically ill patients. However, nutrient supplementation should be done with caution due to the limited availability of randomized controlled studies.

Nanoantidote for repression of acidosis pH promoting COVID-19 infection

Acidosis, such as respiratory acidosis and metabolic acidosis, can be induced by coronavirus disease 2019 (COVID-19) infection and is associated with increased mortality in critically ill COVID-19 patients. It remains unclear whether acidosis further promotes SARS-CoV-2 infection in patients, making virus removal difficult. For antacid therapy, sodium bicarbonate poses great risks caused by sodium overload, bicarbonate side effects, and hypocalcemia. Therefore, new antacid antidote is urgently needed. Our study showed that an acidosis-related pH of 6.8 increases SARS-CoV-2 receptor angiotensin-converting enzyme 2 (ACE2) expression on the cell membrane by regulating intracellular microfilament polymerization, promoting SARS-CoV-2 pseudovirus infection. Based on this, we synthesized polyglutamic acid-PEG materials, used complexation of calcium ions and carboxyl groups to form the core, and adopted biomineralization methods to form a calcium carbonate nanoparticles (CaCO3-NPs) nanoantidote to neutralize excess hydrogen ions (H+), and restored the pH from 6.8 to approximately 7.4 (normal blood pH). CaCO3-NPs effectively prevented the heightened SARS-CoV-2 infection efficiency due to pH 6.8. Our study reveals that acidosis-related pH promotes SARS-CoV-2 infection, which suggests the existence of a positive feedback loop in which SARS-CoV-2 infection-induced acidosis enhances SARS-CoV-2 infection. Therefore, antacid therapy for acidosis COVID-19 patients is necessary. CaCO3-NPs may become an effective antacid nanoantidote superior to sodium bicarbonate.

Promising Therapeutic Approach for SARS-CoV-2 Infections by Using a Rutin-Based Combination Therapy

The development of new therapeutic approaches for SARS-CoV-2 infections is of particular current importance. The combination therapy proposed here is based on already proven, safe and inexpensive compounds. The natural compound rutin, one of the six therapy components, has the potential to inhibit both viral and host cell targets. In addition, this therapy involves the use of acetylsalicylic acid, vitamin C and vitamin D3 , which should be administered together with calcium and magnesium. The importance of each component is briefly described in this article. Due to multiple anti-infective properties of rutin, it provides a basis for combating a SARS-CoV-2 infection as well as various viral and bacterial co-infections. There are strong indications for a good effect of this simple combination therapy, especially in the early stages of infection. It has the potential to be of interest both prophylactically and therapeutically, and offers the possibility of protection against severe disease progression.

Hypocalcemia in COVID-19: Prevalence, clinical significance and therapeutic implications

COVID-19 extra-pulmonary features include several endocrine manifestations and these are becoming strongly clinically relevant in patients affected influencing disease severity and outcomes.At the beginning of COVID-19 pandemic no population data on calcium levels in patients affected were available and in April 2020 a first case of severe acute hypocalcemia in an Italian patient with SARS-CoV-2 infection was reported. Subsequently, several studies reported hypocalcemia as a highly prevalent biochemical abnormality in COVID-19 patients with a marked negative influence on disease severity, biochemical inflammation and thrombotic markers, and mortality. Also a high prevalence of vertebral fractures with worse respiratory impairment in patients affected and a widespread vitamin D deficiency have been frequently observed, suggesting an emerging "Osteo-Metabolic Phenotype" in COVID-19.To date, several potential pathophysiological factors have been hypothesized to play a role in determining hypocalcemia in COVID-19 including calcium dependent viral mechanisms of action, high prevalence of hypovitaminosis D in general population, chronic and acute malnutrition during critical illness and high levels of unbound and unsaturated fatty acids in inflammatory responses.Since hypocalcemia is a frequent biochemical finding in hospitalized COVID-19 patients possibly predicting worse outcomes and leading to acute cardiovascular and neurological complications if severe, it is reasonable to assess, monitor and, if indicated, replace calcium at first patient hospital evaluation and during hospitalization.

The prognostic role of micronutrient status and supplements in COVID-19 outcomes: A systematic review

Micronutrients constitute an adjuvant treatment for respiratory viral infections. Since there is no effective antiviral therapy for COVID-19 yet, adjuvant intervention for the survival of critically ill patients may be significant. Search of the PubMed, CINAHL and Cochrane databases was carried out to find human studies investigating the prognostic role of micronutrient status and the effects of micronutrient supplementation intervention in COVID-19 outcomes of adult patients. Patients with certain comorbidities (diabetes mellitus type 2, obesity, renal failure, liver dysfunction etc.) or pregnant women were excluded. 31 studies (27 observational studies and 4 clinical trials) spanning the years 2020-2021, pertaining to 8624 COVID-19 patients (mean age±SD, 61 ± 9 years) were included in this systematic review. Few studies provided direct evidence on the association of serum levels of vitamin D, calcium, zinc, magnesium, phosphorus and selenium to patients' survival or death. Vitamin D and calcium were the most studied micronutrients and those with a probable promising favorable impact on patients. This review highlights the importance of a balanced nutritional status for a favorable outcome in COVID-19. Micronutrients' deficiency on admission to hospital seems to be related to a high risk for ICU admission, intubation and even death. Nevertheless, evidence for intervention remains unclear.

Lower plasma calcium associated with COVID-19, but not with disease severity: a two-centre retrospective cohort study

BACKGROUND

Previous studies indicate hypocalcaemia as a potential diagnostic and prognostic marker of corona-virus disease 2019 (COVID-19). Our aim was to investigate these relations in more detail in a large test cohort and an independent validation cohort.

METHODS

We retrospectively included 2792 COVID-19 suspected patients that presented to the emergency department (ED) of two hospitals. Plasma calcium and ionized plasma calcium levels were compared between COVID-19 positive and negative patients, and between severe and non-severe COVID-19 patients using univariate and multivariate analyses in the first hospital (N = 1363). Severe COVID-19 was defined as intensive care unit (ICU) admission or death within 28 d after admission. The results were validated by repeating the same analyses in the second hospital (N = 1429).

RESULTS

A total of 693 (24.8%) of the enrolled patients were COVID-19 positive, of whom 238 (34.3%) had severe COVID-19. In both hospitals, COVID-19 positive patients had lower plasma calcium levels than COVID-19 negative patients, regardless of correction for albumin, in univariate and multivariate analysis (Δ0.06-0.13 mmol/L, p < .001). Ionized plasma calcium concentrations, with and without correction for pH, were also lower in COVID-19 positive patients in multivariate analyses (Δ0.02-0.05 mmol/L, N = 567, p < .001). However, we did not find a significant association between COVID-19 disease severity and plasma calcium in multivariate analyses.

CONCLUSIONS

Plasma calcium concentrations were lower in COVID-19 positive than COVID-19 negative patients but we found no association with disease severity in multivariate analyses. Further understanding of plasma calcium perturbation may facilitate the development of new preventive and therapeutic modalities for the current pandemic.

Components of the Mediterranean Diet and Risk of COVID-19

Adherence to the traditional Mediterranean diet has been customarily assessed with the Mediterranean diet score (MDS or Trichopolou Index), with values of 0 or 1 assigned to each of the nine elements, and with the use of the sex-specific median as the cutoff. The value of persons whose consumption of the six beneficial items (ratio of monounsaturated to saturated fatty acids, vegetables, legumes, fruits and nuts, cereal, and fish) is at or above the median and is assigned a value of 1. Otherwise they receive 0 points. For detrimental elements (meats and dairy products) persons whose consumption is below the median are assigned a value of 1. An additional ninth point is assigned to moderate ethanol intake. We assessed the effect of each of the nine components of the MDS (replacing the fats ratio with olive oil, the main source of monounsaturated fats in the Mediterranean diet) on the risk of COVID-19 infection, symptomatic and severe COVID-19. From March to December 2020, 9,699 participants of the "Seguimiento Universidad de Navarra" (SUN) cohort answered a COVID-19 questionnaire. After excluding doctors and nurses, 5,194 participants were included in the main statistical analyses. Among them, we observed 382 cases of COVID-19 based on symptoms and clinical diagnosis; 167 of them with test confirmation. For the two COVID-19 definitions used, we found a significant decrease in risk for a higher adherence to the Mediterranean diet (OR = 0.64, 95% CI: 0.42-0.98, p for trend = 0.040; and OR = 0.44, 95% CI: 0.22-0.88, p for trend = 0.020, for test-diagnosed cases). A protective effect was also found for symptomatic COVID-19 (OR = 0.64, 95% CI: 0.41-1.00, p for trend = 0.050). Among the different individual food groups, only the consumption of whole dairy products showed a harmful direct association. The Mediterranean diet as a whole seems more important than each of its components in preventing the infection and symptoms of COVID-19.

Non-linear relationship between albumin-corrected calcium and 30-day in-hospital mortality in ICU patients: A multicenter retrospective cohort study

OBJECTIVE

Albumin-corrected calcium is usually calculated to reflect the real serum calcium level of the whole body by physicians. However, studies on the association between albumin-corrected calcium and 30-day in-hospital mortality in Intensive Care Unit (ICU) patients are rare. The purpose of our study was to explore the association between baseline albumin-corrected calcium and 30-day in-hospital mortality in the American ICU population.

METHODS

A multicenter retrospective cohort study of 102,245 ICU patients in the eICU-CRD v2.0 from the USA during 2014-2015 was performed. The average age was 63.7 ± 16.9 years, of which 55,313 (53.7%) were men and 47,758 (46.3%) were women. The association between albumin-corrected calcium and 30-day in-hospital mortality was analyzed by Cox proportional-hazards regression, smooth curve fitting, piecewise linear regression, subgroup analyses, and a series of sensitivity analyses.

RESULTS

We found that among ICU patients with calcium abnormalities, more than 95% were mild hypocalcemia or mild hypercalcemia. The risk of 30-day in-hospital mortality will increase by 10% in the ≥7.5-< 8.5 mg/dl subgroup (OR=1.1, 95% CI 1.0-1.3) or 20% in the ≥10.3-<12 mg/dl subgroup (OR=1.2, 95% CI 1.1-1.3) when the albumin-corrected calcium level increases by 1 mg/dl. Additionally, the relationship between albumin-corrected calcium and 30-day in-hospital mortality was U shaped; the inflection point was 8.9 mg/dl (log likelihood ratio test P = 0.005). Finally, after a series of sensitivity analyses, we found that the relationship between albumin-corrected calcium and 30-day in-hospital mortality remained significant.

CONCLUSION

In a large nationally representative cohort of ICU patients, abnormalities in albumin-corrected calcium, particularly slight hypocalcemia or slight hypercalcemia, were associated with an increased 30-day in-hospital mortality risk, and yet the findings in this study need to be further confirmed by prospective studies.

Retrospective case-control study to evaluate hypocalcaemia as a distinguishing feature of COVID-19 compared with other infective pneumonias and its association with disease severity

OBJECTIVES

To investigate whether calcium derangement was a specific feature of COVID-19 that distinguishes it from other infective pneumonias, and its association with disease severity.

DESIGN

A retrospective observational case-control study looking at serum calcium on adult patients with COVID-19, and community-acquired pneumonia (CAP) or viral pneumonia (VP).

SETTING

A district general hospital on the outskirts of London, UK.

PARTICIPANTS

506 patients with COVID-19, 95 patients with CAP and 152 patients with VP.

OUTCOME MEASURES

Baseline characteristics including hypocalcaemia in patients with COVID-19, CAP and VP were detailed. For patients with COVID-19, the impact of an abnormally low calcium level on the maximum level of hospital care, as a surrogate of COVID-19 severity, was evaluated. The primary outcome of maximal level of care was based on the WHO Clinical Progression Scale for COVID-19.

RESULTS

Hypocalcaemia was a specific and common clinical finding in patients with COVID-19 that distinguished it from other respiratory infections. Calcium levels were significantly lower in those with severe disease. Ordinal regression of risk estimates for categorised care levels showed that baseline hypocalcaemia was incrementally associated with OR of 2.33 (95% CI 1.5 to 3.61) for higher level of care, superior to other variables that have previously been shown to predict worse COVID-19 outcome. Serial calcium levels showed improvement by days 7-9 of admission, only in survivors of COVID-19.

CONCLUSION

Hypocalcaemia is specific to COVID-19 and may help distinguish it from other infective pneumonias. Hypocalcaemia may independently predict severe disease and warrants detailed prognostic investigation. The fact that decreased serum calcium is observed at the time of clinical presentation in COVID-19, but not other infective pneumonias, suggests that its early derangement is pathophysiological and may influence the deleterious evolution of this disease.

TRIAL REGISTRATION NUMBER

20/HRA/2344.

The effect of low serum calcium level on the severity and mortality of Covid patients: A systematic review and meta-analysis

INTRODUCTION

Imbalances of various electrolytes, including calcium, are associated with the prognosis of Covid disease. This study investigated the relationship between serum calcium and clinical outcomes in patients with COVID-19.

METHOD

This study is a systematic review and meta-analysis by searching PubMed, Scopus, web of sciences until August 2021 using the keywords COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), COVID, coronavirus disease, SARS-COV-infection. 2, SARS-COV-2, COVID19, calcium, calcium isotopes, calcium radioisotopes, hypercalcemia, and hypocalcemia were performed. Heterogeneity of studies was investigated using I2 index, data were analyzed using meta-analysis (random effects model) with Comprehensive Meta-Analysis Software software.

RESULTS

Finally, 25 articles were included in the study. Clinical data from 12 articles showed that 59% (95% confidence interval [CI]: 0.49-0.68) of people with COVID-19 have hypocalcemia. The results of meta-analysis showed that hypocalcemia was significantly associated with severity of the disease (p = .002), mortality in patients with COVID-19 (odds ratio [OR] = 6.99, 95% CI: 2.71-17.99), number of hospitalization days (p < .001) and admission to the intensive care unit (OR = 5.09, 95% CI: 2.14-12.10). The results also showed that there is a direct relationship between low serum calcium levels with increasing D-dimer levels (p = .02) and decreasing lymphocyte counts (p = .007).

CONCLUSION

Based on the results of meta-analysis in people with lower calcium, mortality and complications are higher, therefore, serum calcium is a prognostic factor in determining the severity of the disease. Consequently, it is suggested that serum calcium levels should be considered in initial assessments.

Altered serum calcium homeostasis independently predicts mortality in patients with acute coronary syndrome: a retrospective observational cohort study

OBJECTIVES

Serum calcium levels (sCa) were reported to be associated with risk of cardiovascular diseases. The aim of this study was to analyse the association between sCa and long-term mortality in patients with acute coronary syndrome (ACS).

DESIGN

A retrospective observational cohort study.

SETTING

Single-centre study with participants recruited from the local area.

PARTICIPANTS

A total of consecutive 13 772 patients with ACS were included in this analysis. Patients were divided based on their sCa profile (≤2.1 mmol/L, 2.1-2.2 mmol/L, 2.2-2.3 mmol/L, 2.3-2.4 mmol/L, 2.4-2.5 mmol/L,>2.5 mmol/L) and followed up for a median of 2.96 years (IQR 1.01-4.07).

PRIMARY OUTCOME

Long-term all-cause mortality.

RESULTS

During a median follow-up period of 2.96 years, patients with sCa ≤2.1 mmol/L had the highest cumulative incidences of all-cause mortality (16.7%), whereas those with sCa 2.4-2.5 mmol/L had the lowest cumulative incidences of all-cause mortality (3.5%). After adjusting for potentially confounding variables, the Cox analysis revealed that compared with the reference group (sCa 2.4-2.5 mmol/L), all the other groups had higher mortality except for the sCa 2.3-2.4 mmol/L group (HR, 1.32, 95% CI 0.93 to 1.87). Restricted cubic splines showed that the relationship between sCa and all-cause mortality seemed to be U shaped. The optimal sCa cut-off point, 2.35 mmol/L, was determined based on the shape of restricted cubic splines.

CONCLUSIONS

Altered serum calcium homeostasis at admission independently predicts all-cause mortality in patients with ACS. In addition, a U-shaped relationship between sCa and all-cause mortality exists, and maintaining sCa at approximately 2.35 mmol/L may minimise the risk of mortality.

Hypocalcemia in COVID-19 is associated with low vitamin D levels and impaired compensatory PTH response

BACKGROUND

Hypocalcemia has been identified as a major distinctive feature of COVID-19, predicting poor clinical outcomes. Among the mechanisms underlying this biochemical finding, high prevalence of vitamin D (VD) deficiency in COVID-19 patients reported so far in several studies was advocated. However, robust data in favor of this hypothesis are still lacking. Therefore, aim of our study was to investigate the role of hypovitaminosis D and parathyroid hormone (PTH) levels in the development of hypocalcemia in COVID-19 patients.

METHODS

Patients admitted to IRCCS Ospedale San Raffaele for COVID-19 were enrolled in this study, excluding those with comorbidities and therapies influencing calcium and VD metabolism. Serum levels of total calcium (tCa), ionized calcium (Ca2+), 25-OH-VD, and PTH were evaluated at admission. We defined VD deficiency as VD below 20 ng/mL, hypocalcemia as tCa below 2.2 mmol/L or as Ca2+ below 1.18 mmol/L, and hyperparathyroidism as PTH above 65 pg/mL.

RESULTS

A total of 78 patients were included in the study. Median tCa and Ca2+ levels were 2.15 and 1.15 mmol/L, respectively. Total and ionized hypocalcemia were observed in 53 (67.9%) and 55 (70.5%) patients, respectively. VD deficiency was found in 67.9% of patients, but secondary hyperparathyroidism was detected in 20.5% of them, only. tCa levels were significantly lower in patients with VD deficiency and regression analyses showed a positive correlation between VD and tCa.

CONCLUSIONS

In conclusion, we confirmed a high prevalence of hypocalcemia in COVID-19 patients and we showed for the first time that it occurred largely in the context of marked hypovitaminosis D not adequately compensated by secondary hyperparathyroidism.

Mineral metabolism and COVID-19: is there a connection?

Due to global spread of COVID-19, the search for new factors that could influence its clinical course becomes highly important. This review summarize the relevant publications on the association between immune system and the main regulators of mineral homeostasis including. In addition, we have highlighted the various aspects of phosphorus-calcium metabolism related to the acute respiratory diseases and in particular to COVID-19. The data about the calcium-phosphorus metabolism in SARS-CoV-2 infection is required to understand the possible clinical implications and to develop new therapeutic and preventive interventions.

Detection of SARS-CoV-2 antibodies in pediatric patients: An Iranian referral hospital-based study

BACKGROUND

As the extent of the pandemic and its seroprevalence pattern has been less clarified in pediatrics to date, we aimed to conduct this study to investigate the clinical and laboratory characteristics of COVID-19 in Iranian children, with a focus on evaluating the antibody prevalence and its relation with the laboratory tests.

METHODS

All children with highly suspected COVID-19 were included. Anti-nucleoprotein SARS-CoV-2 were measured using SARS-CoV-2 immunoglobulin M (IgM) and SARS-CoV-2 IgG ELISA kits. Hypothesis testing was carried out through SPSS to unravel any association between the measurement tools and important clinical and laboratory characteristics.

RESULTS

In this study, 254 patients were evaluated and 117 cases (46%) were male. The nucleic acid detection results for patient 55 were negative, but the IgM and IgG results were positive. Totally, 190 patients were tested for IgM in which only 14 (7.3%) had positive tests. Positive IgG was detected in 51 (20%) out of 254 patients; among them, 30 patients had negative SARS-CoV-2 RT-PCR (59%). Lower level of platelets in IgG positive group in comparison with the IgG negative group was observed (P value: 0.015). Moreover, higher alanine aminotransferase (ALT) was observed in the in IgG positive group (P value: 0.02). In patients with positive IgM, relative hypocalcemia (median of 8.25; IQR: 8.02-8.62) was found which appeared to be significant (P value: 0.02).

CONCLUSION

This is the first largest study describing the SARS-CoV-2 seropositivity among children in Iran and provides important insight about the COVID-19 infection in children.

Serum Zinc, Copper, and Other Biometals Are Associated with COVID-19 Severity Markers

The objective of the present study was to evaluate of serum metal levels in COVID-19 patients with different disease severity, and to investigate the independent association between serum metal profile and markers of lung damage. The cohort of COVID-19 patients consisted of groups of subjects with mild, moderate, and severe illness, 50 examinees each. Forty-four healthy subjects of the respective age were involved in the current study as the control group. Serum metal levels were evaluated using inductively-coupled plasma mass-spectrometry. Examination of COVID-19 patients demonstrated that heart rate, respiratory rate, body temperature, C-reactive protein levels, as well as lung damage increased significantly with COVID-19 severity, whereas SpO₂ decreased gradually. Increasing COVID-19 severity was also associated with a significant gradual decrease in serum Ca, Fe, Se, Zn levels as compared to controls, whereas serum Cu and especially Cu/Zn ratio were elevated. No significant group differences in serum Mg and Mn levels were observed. Serum Ca, Fe, Se, Zn correlated positively with SpO₂, being inversely associated with fever, lung damage, and C-reactive protein concentrations. Opposite correlations were observed for Cu and Cu/Zn ratio. In regression models, serum Se levels were inversely associated with lung damage independently of other markers of disease severity, anthropometric, biochemical, and hemostatic parameters. Cu/Zn ratio was also considered as a significant predictor of lower SpO₂ in adjusted regression models. Taken together, these findings demonstrated that metal metabolism significantly interferes with COVID-19 pathogenesis, although the causal relations as well as precise mechanisms are yet to be characterized.

Multisystem Inflammatory Syndrome in Children Related to SARS-CoV-2

Although data on the incidence and severity of new coronavirus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection showed more significant disease among adults and the elderly, a clinical manifestation characterized by a multisystem inflammatory syndrome was described in children (MIS-C). It was initially thought to be specific to children, but recent reports have shown that it can also occur in adults. MIS-C is characterized by a number of multisystemic manifestations resembling other known previously described illnesses, mainly Kawasaki disease, especially in cases with shock, toxic shock syndrome, and macrophage activation syndrome. Available literature shows that our knowledge of MIS-C is largely incomplete. Its development in strict relation with SARS-CoV-2 infection seems documented and, in most cases, can be considered a post-infectious manifestation secondary to an abnormal immune response for some aspects, similar to that seen in adults several days after SARS-CoV-2 infection. However, in a minority of cases, a clinical picture with symptoms fulfilling criteria for MIS-C diagnosis develops during the acute phase of SARS-CoV-2 infection. It is highly likely that the criteria currently used to diagnose MIS-C are too broad, meaning that children with different diseases are included. As clarity on the pathogenesis of MIS-C is lacking, different therapeutic approaches have been used, but no specific therapy is currently available. Further studies are urgently needed to improve our definition of MIS-C, to define the real impact on child health, and to elucidate the best clinical and therapeutic approach and true prognosis.

Hypocalcemia is associated with severe COVID-19: A systematic review and meta-analysis

BACKGROUND AND AIMS

Hypocalcemia is commonly in critically ill patients and studies have shown that hypocalcemia is prevalent in patients with COVID-19. This meta-analysis aimed to evaluate the prognostic performance of hypocalcemia in patients with coronavirus disease 2019 (COVID-19).

METHODS

We performed a systematic literature search on PubMed, Scopus, and Embase with keywords "SARS-CoV-2″ OR″COVID-19″ OR ″2019-nCoV" AND "hypocalcemia" up until 10 December 2020. The key exposure was hypocalcemia, defined as serum calcium below study-defined cut-off points. The main outcome was poor outcome, which was a composite of mortality and severity. The effect estimate of the main outcome was reported as odds ratio (OR) and its 95% confidence interval (95% CI). We also generate sensitivity, specificity, positive and negative likelihood ratio (PLR & NLR), diagnostic odds ratio (DOR), and area under curve (AUC).

RESULTS

There are 2032 patients from 7 studies included in this systematic review and meta-analysis. The incidence of poor outcome in this study was 26%. Serum calcium was lower in patients with poor outcome (mean difference -0.173 mmol/L [-0.259, -0.087], p < 0.001; I2: 31.3%). Hypocalcemia was associated with poor outcome (OR 3.19 [2.02, 5.06], p < 0.001; I2: 32.86%); with sensitivity of 0.74 [0.53, 0.88], specificity of 0.54 [0.29, 0.77], PLR of 1.6 [1.1, 2.3], NLR of 0.49 [0.35, 0.66], DOR of 3 [2, 5], and AUC of 0.70 [0.66, 0.74]. In this pooled analysis, the post-test probability was 36% in patients with hypocalcemia and 15% in patients without hypocalcemia.

CONCLUSION

Hypocalcemia was associated with poor outcome in COVID-19 patients.

PROSPERO ID

CRD42020225506.