Molecular Aspects and Treatment of Iron Deficiency in the Elderly

Associations of iron metabolism and inflammation with all-cause and cardiovascular mortality in a large NHANES community sample: Moderating and mediating effects

BACKGROUND AND AIMS

This study aimed to assess the associations between serum iron concentration, C-reactive protein (CRP) concentration and the risk of all-cause mortality and cardiovascular mortality in the general population and to explore potential mediating and moderating effects.

METHODS AND RESULTS

This study analyzed data from the National Health and Nutrition Examination Survey spanning the years 1999-2010, encompassing 23,634 participants. Cox proportional hazards regression models were employed to investigate the independent associations of serum iron and CRP with all-cause and cardiovascular mortality. Moderation and mediation analyses explored the moderating effect of CRP on the association between the serum iron concentration and all-cause and cardiovascular mortality, and the mediating role of the serum iron concentration in the association between the CRP concentration and all-cause and cardiovascular mortality. After multivariate adjustments in the Cox model, serum iron and CRP levels were independently correlated with both all-cause and cardiovascular mortality risk. Moderation analyses revealed a more pronounced correlation between the serum iron concentration and both all-cause and cardiovascular mortality in participants with higher CRP levels. Mediation analysis indicated that the serum iron concentration partly mediated the impact of CRP on the risk of all-cause mortality (13.79%) and cardiovascular mortality (24.12%).

CONCLUSION

Serum iron and CRP are independently associated with all-cause and cardiovascular mortality. Moreover, the associations between serum iron concentrations and both all-cause and cardiovascular mortality are more pronounced in individuals with elevated CRP. Serum iron partially mediates the effect of CRP on all-cause and cardiovascular mortality.

Effects of Iron Status on Adaptive Immunity and Vaccine Efficacy: A Review

Vaccines can prevent infectious diseases, but their efficacy varies, and factors impacting vaccine effectiveness remain unclear. Iron deficiency is the most common nutrient deficiency, affecting >2 billion individuals. It is particularly common in areas with high infectious disease burden and in groups that are routinely vaccinated, such as infants, pregnant women, and the elderly. Recent evidence suggests that iron deficiency and low serum iron (hypoferremia) not only cause anemia but also may impair adaptive immunity and vaccine efficacy. A report of human immunodeficiency caused by defective iron transport underscored the necessity of iron for adaptive immune responses and spurred research in this area. Sufficient iron is essential for optimal production of plasmablasts and IgG responses by human B-cells in vitro and in vivo. The increased metabolism of activated lymphocytes depends on the high-iron acquisition, and hypoferremia, especially when occurring during lymphocyte expansion, adversely affects multiple facets of adaptive immunity, and may lead to prolonged inhibition of T-cell memory. In mice, hypoferremia suppresses the adaptive immune response to influenza infection, resulting in more severe pulmonary disease. In African infants, anemia and/or iron deficiency at the time of vaccination predict decreased response to diphtheria, pertussis, and pneumococcal vaccines, and response to measles vaccine may be increased by iron supplementation. In this review, we examine the emerging evidence that iron deficiency may limit adaptive immunity and vaccine responses. We discuss the molecular mechanisms and evidence from animal and human studies, highlight important unknowns, and propose a framework of key research questions to better understand iron-vaccine interactions.

Hospitalization of patients with nutritional anemia in the United States in 2020

Background

Nutritional anemia is highly prevalent and has triggered a globally recognized public health concern worldwide.

Objective

To better understand the prevalence of anemia and the state of nutritional health in developed countries to inform global nutritional health and better manage the disease.

Method

We employed the Healthcare Cost and Utilization Project (HCUP)-2020 National Inpatient Health Care Data (NIS), administered by The Agency for Healthcare Research and Quality. Nutritional anemia was diagnosed according to the International Classification of Diseases, 10th Revision (ICD-10). Matching analysis and multivariate regression were used to adjust for patient and hospital characteristics. Controls were obtained by stratifying and matching for age and sex.

Results

The 2020 HCUP-NIS database encompassed a survey over 6.4 million hospitalized patients, among which 1,745,350 patients diagnosed with anemia, representing approximately 26.97% of the hospitalized population, over 310,000 were diagnosed with nutritional anemia, and 13,150 patients were hospitalized for nutritional anemia as primary diagnosis. Hospitalization rate for nutritional anemia exhibited an increased age-dependent increase nationwide, especially among females, who displayed 1.87 times higher than males. Notably, in comparison to the control group, individuals of the Black race exhibit a higher prevalence of nutritional anemia (case group: 21.7%, control group: 13.0%, p < 0.001). In addition, hospitalization rates were higher among low-income populations, with lower rates of private insurance (case group: 18.7%, control group: 23.5%, p < 0.001) and higher rates of Medicaid insurance (case group: 15.4%, control group: 13.9%, p < 0.001). In areas characterized by larger urban centers and advanced economic conditions within the urban-rural distribution, there was an observed increase in the frequency of patient hospitalizations. Iron deficiency anemia emerged as the predominant subtype of nutritional anemia, accounting for 12,214 (92.88%). Secondary diagnosis among patients hospitalized for nutritional anemia revealed that a significant number faced concurrent major conditions like hypertension and renal failure.

Conclusion

In economically prosperous areas, greater attention should be given to the health of low-income individuals and the older adult. Our findings hold valuable insights for shaping targeted public health policies to effectively address the prevalence and consequences of nutritional anemia based on a overall population health.

Effects of ferric derisomaltose on postoperative anaemia in adult spinal deformity surgery: a study protocol for a randomised controlled trial

INTRODUCTION

Postoperative anaemia is prevalent in adult spinal deformity (ASD) surgery in association with unfavourable outcomes. Ferric derisomaltose, a novel iron supplement, offers a promising solution in rapidly treating postoperative anaemia. However, the clinical evidence of its effect on patients receiving spinal surgery remains inadequate. This randomised controlled trial aims to evaluate the safety and efficacy of ferric derisomaltose on postoperative anaemia in ASD patients.

METHODS AND ANALYSIS

This single-centre, phase 4, randomised controlled trial will be conducted at Department of Orthopaedics at Peking Union Medical College Hospital and aims to recruit adult patients who received ASD surgery with postoperative anaemia. Eligible participants will be randomly assigned to receive ferric derisomaltose infusion or oral ferrous succinate. The primary outcome is the change in haemoglobin concentrations from postoperative days 1-14. Secondary outcomes include changes in iron parameters, reticulocyte parameters, postoperative complications, allogeneic red blood cell infusion rates, length of hospital stay, functional assessment and quality-of-life evaluation.

ETHICS AND DISSEMINATION

This study has been approved by the Research Ethics Committee of Peking Union Medical College Hospital and registered at ClinicalTrials.gov. Informed consent will be obtained from all participants prior to enrolment and the study will be conducted in accordance with the principles of the Declaration of Helsinki. The results of this study are expected to be disseminated through peer-reviewed journals and academic conferences.

TRIAL REGISTRATION NUMBER

NCT05714007.

Exploring the Relationship between Epicardial Fat Thickness and Coronary Revascularization: Implications for Cardiovascular Health

BACKGROUND

this study aimed to assess the complex relationship between EAT thickness, as measured with echocardiography, and the severity of coronary artery disease (CAD). We investigated whether individuals with higher EAT thickness underwent coronary revascularization. Subsequently, we conducted a three-year follow-up to explore any potential modifications in EAT depots post-angioplasty.

METHODS

we conducted a prospective and retrospective cross-sectional observational study involving 150 patients consecutively referred for acute coronary syndrome, including ST-elevation myocardial infarction (STEMI), non-ST elevation myocardial infarction (NSTEMI), and unstable angina. Upon admission (T0), all patients underwent coronary angiography to assess the number of pathologic coronary vessels. Percutaneous transluminal coronary angioplasty (PTCA) was performed based on angiogram results if indicated. The sample was categorized into two groups: non-revascularized (no-PTCA) and revascularized (PTCA). Transthoracic echocardiograms to measure epicardial fat thickness were conducted at admission (T0) and after a 3-year follow-up (T1).

RESULTS AND CONCLUSIONS

findings revealed a positive correlation between EAT thickness and the severity of coronary artery disease (CAD), with patients undergoing PTCA showing decreased EAT thickness after three years. Echocardiography demonstrated reliability in assessing EAT, offering potential for risk stratification. The study introduces a cut-off value of 0.65 cm as a diagnostic tool for cardiovascular risk. Incorporating EAT measurements into clinical practice may lead to more precise risk stratification and tailored treatment strategies, ultimately reducing the burden of cardiovascular disease.

Micronutrient Deficiencies in Older Adults in Latin-America: A Narrative Review

BACKGROUND

The population in Latin America and Caribbean (LAC) has experienced a major demographic transition with increased numbers of older adults (OA). This change brings opportunities in the public health sector to implement health prevention interventions and delay the onset of geriatric syndromes. Micronutrients play an important role in the maintenance of biological function which contributes to longevity. Micronutrient deficiencies (MD) in OA increase the risk for onset of chronic comorbidities and geriatric syndromes.

AIM

To review and summarize the existing data on micronutrient status in OA in the LAC region and discuss the gaps and challenges in public health approaches to address deficiencies.

METHODS

Literature review in Medline for records describing nutritional biomarkers in older adults (≥ 60y) from community dwelling and population-based studies in LAC.

RESULTS

Few countries (including Chile, Ecuador, Costa Rica, Brazil, and Mexico) have documented one or more nutritional deficiencies for OA in national health surveys, however across the entire region, evidence of micronutrient levels is scarce. Some surveys have documented a high prevalence and large heterogeneity in the prevalence of vitamin D followed by B12 deficiency, being the 2 MDs most studied due their effects on cognition, frailty, and bone mineral density in the OA population. Other MD including C, E, A, copper, zinc, iron, and selenium have also been reported.

CONCLUSION

Information on the micronutrient status in OA from LAC is poorly documented. Research and capacity building initiatives in the region are crucial to develop tailored strategies that address the specific nutritional needs and challenges faced by the ageing population in Latin-America.

Etiology of Anemia and Risk Factors of Mortality among Hospitalized Patients: A Real-Life Retrospective Study in a Tertiary Center in Greece

Anemia is a prominent global health issue with a wide variety of causes and can be associated with decreased quality of life, increased hospitalization, and higher mortality, especially in older individuals. Therefore, studies further shedding light on the causes and the risk factors of this condition should be performed. The aim of the present study was to examine the causes of anemia in hospitalized patients in a tertiary hospital in Greece and identify risk factors related to higher mortality. In total, 846 adult patients with a diagnosis of anemia were admitted during the study period. The median age was 81 years, and 44.8% were male. The majority of patients had microcytic anemia, with the median mean corpuscular volume (MCV) being 76.3 fL and the median hemoglobin being 7.1 g/dL. Antiplatelets were used by 28.6% of patients, while 28.4% were using anticoagulants at the time of diagnosis. At least one unit of packed red blood cells (PRBCs) was transfused in 84.6% of patients, and a median of two PRBCs was used per patient. A gastroscopy was performed in 55%, and a colonoscopy was performed in 39.8% of patients in the present cohort. Anemia was considered to be multifactorial in almost half the cases, while the most commonly identified cause was iron deficiency anemia, more commonly with positive endoscopic findings. Mortality was relatively low, at 4.1%. Multivariate logistic regression analysis identified higher B12 levels and longer duration of hospital stay to be independently positively associated with mortality.

Red Cell Distribution Width as a Predictive Factor of Celiac Disease in Middle and Late Adulthood and Its Potential Utility as Celiac Disease Screening Criterion

Red cell distribution width (RDW) could be of interest by its potential use in the assessment of celiac disorder (CD). The main objective of this study was to evaluate the case positive rate of CD and the utility of red cell distribution width (RDW) in the CD diagnosis. This prospective study included 9.066 middle adult (≥45 years old) and elderly patients (≥60 years old) from 2012 to 2021. CD diagnosis was performed by CD antibody tests (serology and Human Leucocyte Antigen genotype (HLA)) and biopsy. Gastrointestinal and extra-intestinal manifestations as well as hematological and biochemical parameters were analyzed. CD diagnoses were confirmed in 101 patients (median (IQR) age = 62 (52.3−73); 68.32% women) by serologic tests (100%) and intestinal biopsy (88.12%), showing mainly marked or complete atrophy (76.24%, MARSH 3a−c). Anemia was the most commonly presenting extra-intestinal manifestation (28.57%). Among 8975 individuals without CD, 168 age and sex matched were included. By comparison of CD and no CD individuals, we observed that high >14.3% RDW was exhibited by 58.40% and 35.2% individuals with CD and without CD, respectively. Furthermore, high RDW is associated with CD and grade III atrophy. We suggest that RDW could be used as a CD screening criterion.

Intravenous ferric derisomaltose in iron-deficient patients undergoing transcatheter aortic valve implantation due to severe aortic stenosis: study protocol of the randomised controlled IIISAS trial

INTRODUCTION

Iron deficiency is a prevalent comorbidity in patients with severe aortic stenosis and may be associated with procedural and clinical outcomes after transcatheter aortic valve implantation (TAVI). In the Intravenous Iron Supplement for Iron Deficiency in Patients with Severe Aortic Stenosis (IIISAS) trial, we aim to examine whether a single administration of ferric derisomaltose can improve physical capacity after TAVI.

METHODS AND ANALYSIS

This randomised, double-blind, placebo-controlled trial aims to enrol 150 patients with iron deficiency who are scheduled for TAVI due to severe aortic stenosis. The study drug and matching placebo are administered approximately 3 months prior to TAVI, and the patients are followed for 3 months after TAVI. Inclusion criteria are iron deficiency, defined as serum ferritin<100 µg/L or ferritin between 100 and 300 µg/L in combination with a transferrin saturation<20% and written informed consent. Exclusion criteria include haemoglobin<10 g/dL, red blood cell disorders, end-stage kidney failure, intolerance to ferric derisomaltose, and ongoing infections. The primary endpoint is the baseline-adjusted distance walked on a 6 min walk test (6MWT) 3 months after TAVI. Secondary end points include quality of life, New York Heart Association functional class (NYHA functional class), and skeletal muscle strength.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Regional Committee for Medical and Health Research of South-Eastern Norway and The Norwegian Medicines Agency. Enrolment has begun, and results are expected in 2022. The results of the IIISAS trial will be disseminated by presentations at international and national conferences and by publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04206228.

Iron imbalance in cancer: Intersection of deficiency and overload

Iron, an essential trace element, plays a complex role in tumour biology. While iron causes cancer clearance through toxic free radical generation, iron‐induced free radical flux also acts as a cancer promoter. These fates majorly guided through cellular response towards pro‐oxidant and antioxidant settings in a tumour microenvironment, designate iron‐induced oxidative stress as a common yet paradoxical factor in pro‐tumorigenesis as well as anti‐tumorigenesis, posing a challenge to laying down iron thresholds favouring tumour clearance. Additionally, complexity of iron's association with carcinogenesis has been extended to iron‐induced ROS's involvement in states of both iron deficiency and overload, conditions identified as comparable, inevitable and significant coexisting contributors as well as outcomes in chronic infections and tumorigenesis. Besides, iron overload may also develop as an unwanted outcome in certain cancer patients, as a result of symptomatic anaemia treatment owed to irrational iron‐restoration therapies without a prior knowledge of body's iron status with both conditions synergistically acting towards tumour aggravation. The co‐play of iron deficiency and overload along with iron's pro‐tumour and antitumour roles with intersecting mechanisms, thus presents an unpredictable regulatory response loop in a state of malignancy. The relevance of iron's thresholds beyond which it proves to be beneficial against tumorigenesis hence becomes questionable. These factors pose a challenge, over establishing if iron chelation or iron flooding acts as a better approach towards antitumour therapies. This review presents a critical picture of multiple contrasting features of iron's behaviour in cancer, leading towards two conditions lying at opposite ends of a spectrum: iron deficiency and overload in chronic disease conditions including cancer, hence, validating the critical significance of diagnosis of patients' iron status prior to opting for subsequent therapies.

Iron

Iron deficiency anemia affects approximately one-third of the world's population, and about half the cases are due to iron deficiency. The latest research on iron metabolism published in original articles and systematic reviews is described, and references to recent reviews provided. The topics include dietary sources and bioavailability, iron homeostasis, functions of iron in the body, and biomarkers of status. The consequences of iron deficiency and excess are discussed, with particular focus on vulnerable populations such as pregnant women, infants and the elderly. The newest dietary recommendations, including dietary reference values and food based dietary guidelines, are briefly summarized, followed by the latest developments in food fortification and iron supplementation.

Altered Expression of Mitoferrin and Frataxin, Larger Labile Iron Pool and Greater Mitochondrial DNA Damage in the Skeletal Muscle of Older Adults

Mitochondrial dysfunction and iron (Fe) dyshomeostasis are invoked among the mechanisms contributing to muscle aging, possibly via a detrimental mitochondrial-iron feed-forward loop. We quantified the labile Fe pool, Fe isotopes, and the expression of mitochondrial Fe handling proteins in muscle biopsies obtained from young and older adults. The expression of key proteins of mitochondrial quality control (MQC) and the abundance of the mitochondrial DNA common deletion (mtDNA4977) were also assessed. An inverse association was found between total Fe and the heavier Fe isotope (56Fe), indicating an increase in labile Fe abundance in cells with greater Fe content. The highest levels of labile Fe were detected in old participants with a Short Physical Performance Battery (SPPB) score ≤ 7 (low-functioning, LF). Protein levels of mitoferrin and frataxin were, respectively, higher and lower in the LF group relative to young participants and older adults with SPPB scores ≥ 11 (high-functioning, HF). The mtDNA4977 relative abundance was greater in old than in young participants, regardless of SPPB category. Higher protein levels of Pink1 were detected in LF participants compared with young and HF groups. Finally, the ratio between lipidated and non-lipidated microtubule-associated protein 1A/1B-light chain 3 (i.e., LC3B II/I), as well as p62 protein expression was lower in old participants regardless of SPPB scores. Our findings indicate that cellular and mitochondrial Fe homeostasis is perturbed in the aged muscle (especially in LF older adults), as reflected by altered levels of mitoferrin and frataxin, which, together with MQC derangements, might contribute to loss of mtDNA stability.