The influence of iron deficiency on the functioning of skeletal muscles: experimental evidence and clinical implications

Exercise training response according to baseline ferrokinetics in heart failure with preserved ejection fraction: A substudy of the TRAINING-HF trial

BACKGROUND

Iron deficiency (ID) is associated with impaired functional capacity in patients with heart failure (HF), even in those with preserved ejection fraction (HFpEF). This study aimed to evaluate the effect of baseline ferrokinetics on peak oxygen consumption (peakVO2) improvement after a 12-week physical therapy programme in patients with stable HFpEF.

METHODS

This study is a post-hoc sub-analysis of a randomized clinical trial in which 59 stable patients with HFpEF were randomized to receive a 12-week programme of inspiratory muscle training (IMT), functional electrical stimulation (FES), IMT + FES or usual care (UC) to evaluate change in peakVO2 (NCT02638961). Serum ferritin and transferrin saturation (TSAT) determinations were assessed at baseline. ID was defined as ferritin <100 ng/mL and/or TSAT <20% if ferritin was within 100-299 ng/mL. We used a linear mixed regression model to analyse between-treatment changes in peakVO2 across ferrokinetics status at 12 and 24 weeks.

RESULTS

The mean age was 74 ± 9 years, and 36 (61%) had ID. The mean of peakVO2 was 9.9 ± 2.5 mL/kg/min. The median of ferritin and transferrin saturation (TSAT) was 91 (50-181) ng/mL and 23% (16-30), respectively. A total of 52 patients completed the trial (13 patients per arm). Compared with those patients on UC, patients allocated to any of the active arms showed less improvement in peak VO2 when they showed ID (P-value for interaction <0.001), lower values of ferritin (P-value for interaction <0.001), or TSAT (P-value for interaction <0.001).

CONCLUSIONS

Ferrokinetics status plays an essential role in modifying the aerobic capacity response to physical therapies in patients with HFpEF. Further studies are required to confirm these findings.

Iron deficiency, anemia, and patient-reported outcomes in kidney transplant recipients

Kidney transplant recipients (KTRs) experience more fatigue, anxiety, and depressive symptoms and lower concentration and health-related quality of life (HRQoL) compared with the general population. Anemia is a potential cause that is well-recognized and treated. Iron deficiency, however, is often unrecognized, despite its potential detrimental effects related to and unrelated to anemia. We investigated the interplay of anemia, iron deficiency, and patient-reported outcomes in 814 outpatient KTRs (62% male, age 56 ± 13 years) enrolled in the TransplantLines Biobank and Cohort Study (Groningen, The Netherlands). In total, 28% had iron deficiency (ie, transferrin saturation < 20% and ferritin < 100 μg/L), and 29% had anemia (World Health Organization criteria). In linear regression analyses, iron deficiency, but not anemia, was associated with more fatigue, worse concentration, lower wellbeing, more anxiety, more depressive symptoms, and lower HRQoL, independent of age, sex, estimated glomerular filtration rate, anemia, and other potential confounders. In the fully adjusted logistic regression models, iron deficiency was associated with an estimated 53% higher risk of severe fatigue, a 100% higher risk of major depressive symptoms, and a 51% higher chance of being at risk for sick leave/work disability. Clinical trials are needed to investigate the effect of iron deficiency correction on patient-reported outcomes and HRQoL in KTRs.

Relationship between hemoglobin and grip strength in older adults: the ActiFE study

INTRODUCTION

Although anemia is associated with low muscle strength, hemoglobin has been rarely studied considering ferritin.

AIM

To analyze the association between hemoglobin and grip strength in community-dwelling older adults.

METHODS

We used data from a German cohort of adults ≥ 65 years, excluding those with CRP > 10 mg/L or taking iron supplements. Grip strength (kg) was measured using a Jamar dynamometer. Analysis was performed using multiple linear regression, adjusted for established confounders. Due to interaction, age-stratified (< 80, 80 +), further sex-stratified analysis in those < 80 years old and ferritin-stratified in men < 80 years were performed.

RESULTS

In total, 1294 participants were included in this analysis (mean age 75.5 years, 549 (42.3%) women, 910 (70.3%) < 80 years). On average, hemoglobin and grip strength were 14.9 g/dL and 41.3 kg for men, 13.9 g/dL and 25.1 kg for women. Hemoglobin was significantly positively associated with grip strength only among women < 80 years (β 0.923 [95% CI 0.196, 1.650]). For men < 80 years, the association was significant when ferritin was ≥ 300 µg/L (β 2.028 [95% CI 0.910, 3.146]). No association was detected among those participants 80 + .

DISCUSSION AND CONCLUSIONS

Our data show an association between hemoglobin and grip strength only in women < 80 years old. For men < 80 years, the association was only significant with ferritin levels ≥ 300 µg/L. Considering the decreasing levels of hemoglobin and grip strength and the high prevalence of iron deficiency in older adults further analyses investigating this relationship with more iron specific parameters such as transferrin saturation are warranted.

Benefits of intravenous iron supplementation in heart failure

Introduction: Iron deficiency (ID) is one of the most frequent comorbidities in patients with heart failure (HF) and is estimated to be present in up to 80% of acute patients regardless of their ejection fraction. Randomized controlled trials have shown that supplementary intravenous iron results in improved clinical outcomes; however, the current understanding of the effects of intravenous iron on morbidity and mortality remains limited. Study and results: The meta-analysis pooled individual participant data from three randomized placebo-controlled trials of ferric carboxymaltose (FCM) in adult patients (n = 4,501) with heart failure and iron deficiency (CONFIRM-HF, AFFIRM-AHF, and HEART-FID). FCM therapy significantly reduced the co-primary composite endpoint of total cardiovascular hospitalizations and cardiovascular death, with a rate ratio (RR 0.86; 95% CI 0.75 to 0.98; p = 0.029). FCM therapy was associated with a 17% relative rate reduction in total cardiovascular hospitalizations (RR 0.83; 95% CI 0.73 to 0.96; p = 0.009) and a 16% relative rate reduction in total heart failure hospitalizations (RR 0.84; 95% CI 0.71 to 0.98; p = 0.025). Lessons learned: The meta-analysis shows that in iron-deficient patients with heart failure and reduced or mildly reduced left ventricular ejection fraction, intravenous ferric carboxymaltose (FCM) is associated with a reduced risk of total cardiovascular hospitalization and cardiovascular mortality. These findings indicate that intravenous FCM should be considered in iron-deficient patients with heart failure and reduced or mildly reduced ejection fractions.

Iron Dyshomeostasis and Mitochondrial Function in the Failing Heart: A Review of the Literature

Cardiac contraction and relaxation require a substantial amount of energy provided by the mitochondria. The failing heart is adenosine triphosphate (ATP)- and creatine-depleted. Studies have found iron is involved in almost every aspect of mitochondrial function, and previous studies have shown myocardial iron deficiency in heart failure (HF). Many clinicians advocated intravenous iron repletion for HF patients meeting the conventional criteria for systemic iron deficiency. While clinical trials showed improved quality of life, iron repletion failed to significantly impact survival or significant cardiovascular adverse events. There is evidence that in HF, labile iron is trapped inside the mitochondria causing oxidative stress and lipid peroxidation. There is also compelling preclinical evidence demonstrating the detrimental effects of both iron overload and depletion on cardiomyocyte function. We reviewed the mechanisms governing myocardial and mitochondrial iron content. Mitochondrial dynamics (i.e., fusion, fission, mitophagy) and the role of iron were also investigated. Ferroptosis, as an important regulated cell death mechanism involved in cardiomyocyte loss, was reviewed along with agents used to manipulate it. The membrane stability and iron content of mitochondria can be altered by many agents. Some studies are showing promising improvement in the cardiomyocyte function after iron chelation by deferiprone; however, whether the in vitro and in vivo findings will be reflected on on clinical grounds is still unclear. Finally, we briefly reviewed the clinical trials on intravenous iron repletion. There is a need for more well-simulated animal studies to shed light on the safety and efficacy of chelation agents and pave the road for clinical studies.

Iron deficiency-induced ferritinophagy impairs skeletal muscle regeneration through RNF20-mediated H2Bub1 modification

Iron deficiency (ID) is a widespread condition concomitant with disease and results in systemic dysfunction of target tissues including skeletal muscle. Activated by ID, ferritinophagy is a recently found type of selective autophagy, which plays an important role in various physiological and pathological conditions. In this study, we demonstrated that ID-mediated ferritinophagy impeded myogenic differentiation. Mechanistically, ferritinophagy induced RNF20 degradation through the autophagy-lysosomal pathway and then negatively regulated histone H2B monoubiquitination at lysine-120 in the promoters of the myogenic markers MyoD and MyoG, which inhibited myogenic differentiation and regeneration. Conditional knockout of NCOA4 in satellite cells, overexpression of RNF20 or treatment with 3-methyladenine restored skeletal muscle regenerative potential under ID conditions. In patients with ID, RNF20 and H2Bub1 protein expression is downregulated in skeletal muscle. In conclusion, our study indicated that the ferritinophagy-RNF20-H2Bub1 axis is a pathological molecular mechanism underlying ID-induced skeletal muscle impairment, suggesting potential therapeutic prospects.

The Link between Trace Metal Elements and Glucose Metabolism: Evidence from Zinc, Copper, Iron, and Manganese-Mediated Metabolic Regulation

Trace metal elements are of vital importance for fundamental biological processes. They function in various metabolic pathways after the long evolution of living organisms. Glucose is considered to be one of the main sources of biological energy that supports biological activities, and its metabolism is tightly regulated by trace metal elements such as iron, zinc, copper, and manganese. However, there is still a lack of understanding of the regulation of glucose metabolism by trace metal elements. In particular, the underlying mechanism of action remains to be elucidated. In this review, we summarize the current concepts and progress linking trace metal elements and glucose metabolism, particularly for the trace metal elements zinc, copper, manganese, and iron.

Disutilities Associated with Intravenous Iron Infusions: Results from a Time Trade-off Survey and Diminishing Marginal Utility Model for Treatment Attributes in China

Purpose

Treatment process attributes can affect health state utilities associated with therapy. For intravenous iron, used to treat iron deficiency and iron deficiency anemia, research into process attributes is still lacking. This study estimated utilities associated with process attributes for intravenous iron infusions.

Methods

An online survey including seven health state vignettes and time trade-off tasks was administered to participants, who were not patients living with iron deficiency or iron deficiency anemia, from a Chinese online panel. Vignettes used an identical description of iron deficiency and iron deficiency anemia but differed in the annual number of infusions, infusion duration, and infusion-associated risk of hypophosphatemic osteomalacia. Disutilities and their rate of change as the number of infusions increased were examined using a power model.

Results

The survey was completed by 1091 participants. The highest utilities were observed for one annual infusion of 15-30 minutes or 30-60 minutes, without risk of hypophosphatemic osteomalacia (0.754 and 0.746, respectively). In comparison, more infusions and infusions with a risk of hypophosphatemic osteomalacia were associated with lower utilities. Utility continued to decrease, but at a diminishing rate, as the annual number of infusions increased, with utility decrements of 0.006 and 0.002, respectively, when going from zero to one and from four to five infusions per year. All marginal disutilities were small (values <0.01).

Conclusion

This study suggested that treatment attributes of intravenous iron infusions affect health state utilities. Using intravenous iron formulations that allow for fewer and shorter infusions without the risk of hypophosphatemic osteomalacia can reduce the number of visits required and increase patients' quality of life.

A Randomized Trial of Intravenous Iron Supplementation and Exercise on Exercise Capacity in Iron-Deficient Nonanemic Patients With CKD

Introduction

Patients with chronic kidney disease (CKD) are often iron deficient, even when not anemic. This trial evaluated whether iron supplementation enhances exercise capacity of nonanemic patients with CKD who have iron-deficiency.

Methods

Prospective, multicenter double-blind randomized controlled trial of nondialysis patients with CKD and iron-deficiency but without anemia (Hemoglobin [Hb] >110 g/l). Patients were assigned 1:1 to intravenous (IV) iron therapy, or placebo. An 8-week exercise program commenced at week 4. The primary outcome was the mean between-group difference in 6-minute walk test (6MWT) at 4 weeks. Secondary outcomes included 6MWT at 12 weeks, transferrin saturation (TSAT), serum ferritin (SF), Hb, renal function, muscle strength, functional capacity, quality of life, and adverse events at baseline, 4 weeks, and at 12 weeks. Mean between-group differences were analyzed using analysis of covariance models.

Results

Among 75 randomized patients, mean (SD) age for iron therapy (n = 37) versus placebo (n = 38) was 54 (16) versus 61 (12) years; estimated glomerular filtration rate (eGFR) (34 [12] vs. 35 [11] ml/min per 1.73 m2], TSAT (23 [12] vs. 21 [6])%; SF (57 [64] vs. 62 [33]) μg/l; Hb (122.4 [9.2] vs. 127 [13.2] g/l); 6MWT (384 [95] vs. 469 [142] meters) at baseline, respectively. No significant mean between-group difference was observed in 6MWT distance at 4 weeks. There were significant increases in SF and TSAT at 4 and 12 weeks (P < 0.02), and Hb at 12 weeks (P = 0.009). There were no between-group differences in other secondary outcomes and no adverse events attributable to iron therapy.

Conclusion

This trial did not demonstrate beneficial effects of IV iron therapy on exercise capacity at 4 weeks. A larger study is needed to confirm if IV iron is beneficial in nondialysis patients with CKD who are iron-deficient.

[Iron deficiency in cardiac surgery patients and the possibility of its correction at the preoperative stage]

Among cardio-surgical patients, the prevalence of iron deficiency conditions reaches 70 %, and anemia is detected in less than 50% cases. Meanwhile, both anemia and latent iron deficiency are risk factors for adverse outcomes in cardio-surgical patients. These conditions are associated with a high frequency and greater volume of blood transfusions as well as with a longer stay in the hospital. Timely diagnosis and correction of iron deficiency, regardless of the presence of anemia, are mandatory at the stage of preoperative preparation. The use of oral iron medicines is limited by their low efficacy in this category of patients and a high risk of adverse events. Intravenous iron medicines have a high potential for correcting iron deficiency, and their efficacy and safety have been previously demonstrated. Administration of ferric carboxymaltose has proved beneficial in studies on iron deficiency correction in cardiological and cardio-surgical patients. In these patients, ferric carboxymaltose improved the dynamics of ferritin and hemoglobin, reduced the risk of blood transfusion, and decreased the duration of stay in the hospital. Preoperative intravenous administration of ferric carboxymaltose to cardio-surgical patients can improve clinical outcomes and the cost effectiveness of cardiac surgery.

Treatment of iron deficiency in patients scheduled for pancreatic surgery: implications for daily prehabilitation practice in pancreatic surgery

BACKGROUND

Preoperative anemia is a frequent complication in pancreatic surgical patients, and it adversely affects morbidity, mortality, and postoperative red blood cell (RBC) transfusion rates. Iron deficiency (ID) is often the underlying cause of anemia and constitutes a modifiable risk factor.

METHODS

Single-center, longitudinal prospective cohort study conducted between May 2019 and August 2022 at the University Medical Center Groningen in the Netherlands. Patients scheduled for pancreatic surgery were referred to the outpatient prehabilitation clinic for preoperative optimization of patient-related risk factors. Patients were screened for anemia (< 12.0 g/dL in women and < 13.0 g/dL in men) and ID (either absolute [ferritin < 30 µg/L] or functional [ferritin ≥ 30 µg/L + transferrin saturation < 20% + C-reactive protein > 5 mg/L]). Intravenous iron supplementation (IVIS) (1,000 mg ferric carboxymaltose) was administered to patients with ID at the discretion of the consulting internist. Pre- and postoperative hemoglobin (Hb) levels were assessed, and perioperative outcomes were compared between patients receiving IVIS (IVIS-group) or standard care (SC-group).

RESULTS

From 164 screened patients, preoperative anemia was observed in 55 (33.5%) patients, and in 23 (41.8%) of these patients, ID was the underlying cause. In 21 patients, ID was present without concomitant anemia. Preoperative IVIS was administered to 25 patients, out of 44 patients with ID. Initial differences in mean Hb levels (g/dL) between the IVIS-group and SC-group at the outpatient clinic and one day prior to surgery (10.8 versus 13.2, p < 0.001, and 11.8 versus 13.4, p < 0.001, respectively) did not exist at discharge (10.6 versus 11.1, p = 0.13). Preoperative IVIS led to a significant increase in mean Hb levels (from 10.8 to 11.8, p = 0.03). Fewer SSI were observed in the IVIS-group (4% versus 25.9% in the SC-group, p = 0.02), which remained significant in multivariable regression analysis (OR 7.01 (1.68 - 49.75), p = 0.02).

CONCLUSION

ID is prevalent in patients scheduled for pancreatic surgery and is amendable to preoperative correction. Preoperative IVIS increased Hb levels effectively and reduced postoperative SSI. Screening and correction of ID is an important element of preoperative care and should be a standard item in daily prehabilitation practice.

Iron Deficiency in Korean Patients With Heart Failure

BACKGROUND

Although iron deficiency (ID) is an important and treatable risk factor for heart failure (HF), data on ID are scarce in Asian patients with HF. Therefore, we sought to determine the prevalence and clinical characteristics of ID in hospitalized Korean patients with HF.

METHODS

In this prospective, multicenter cohort study, 461 patients with acute HF seen at five tertiary centers from January to November 2019 in Korea were enrolled. ID was defined as serum ferritin < 100 μg/L or ferritin 100-299 μg/L in combination with transferrin saturation < 20%.

RESULTS

The patients' mean age was 67.6 ± 14.9 years, and 61.8% were male. Among total 461 patients, ID was present in 248 patients (53.8%). The prevalence of ID was significantly higher in women than in men (65.3% vs. 47.3%, P < 0.001). In a multivariable logistic regression analysis, the independent predictors of ID were female sex (odds ratio [OR], 2.19; 95% confidence interval [CI], 1.47-3.30), valvular heart disease (OR, 2.10; 95% CI, 1.10-4.17), higher heart rate (OR, 1.10; 95% CI, 1.01-1.21), anemia (OR, 1.60; 95% CI, 1.07-2.40), and the use of clopidogrel (OR, 1.56; 95% CI, 1.00-2.45). Among women, the prevalence of ID did not significantly differ between younger and older women (< 65 years: 73.7% vs. ≥ 65 years: 63.0%, P = 0.222), those with low and high body mass index (BMI < 25 kg/m²: 66.2% vs. BMI ≥ 25 kg/m²: 69.6%, P = 0.703), or those with low and high natriuretic peptide (NP) levels (NP < median: 69.8% vs. NP ≥ median: 61.1%, P = 0.295). Only 0.2% patients with acute HF received intravenous iron supplementation in Korea.

CONCLUSION

The prevalence of ID is high in hospitalized Korean patients with HF. Because ID cannot be diagnosed by clinical parameters, routine laboratory examinations are necessary to identify patients with ID.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04812873.

Magnetic resonance imaging of organ iron before and after correction of iron deficiency in patients with heart failure

AIMS

Intravenous iron therapy (IVIT) is known to improve functional status in chronic heart failure (CHF) patients. The exact mechanism is not completely understood. We correlated magnetic resonance imaging (MRI) patterns of T2* iron signal in various organs to systemic iron and exercise capacity (EC) in CHF before and after IVIT.

METHODS AND RESULTS

We prospectively analysed 24 patients with systolic CHF for T2* MRI pattern of the left ventricle (LV), small and large intestines, spleen, liver, skeletal muscle, and brain for iron. In 12 patients with iron deficiency (ID), we restored iron deficit by IVIT using ferric carboxymaltose. The effects after 3 months were analysed by spiroergometry and MRI. Patients with vs. without ID showed lower blood ferritin, haemoglobin (76 ± 63 vs. 196 ± 82 μg/L and 12.3 ± 1.1 vs. 14.2 ± 1.1 g/dL, all P < 0.002), and in trend a lower transferrin saturation (TSAT) (19.1 [13.1; 28.2] vs. 25.1 [21.3; 29.1] %, P = 0.05). Spleen and liver iron was lower as expressed by higher T2* value (71.8 [66.4; 93.1] vs. 36.9 [32.9; 51.7] ms, P < 0.002 and 33.5 ± 5.9 vs. 28.8 ± 3.9 ms, and P < 0.03). There was a strong trend for a lower cardiac septal iron content in ID (40.6 [33.0; 57.3] vs. 33.7 [31.3; 40.2] ms, P = 0.07). After IVIT, ferritin, TSAT, and haemoglobin increased (54 [30; 104] vs. 235 [185; 339] μg/L, 19.1 [13.1; 28.2] vs. 25.0 [21.0; 33.7] %, 12.3 ± 1.1 vs. 13.3 ± 1.3 g/L, all P < 0.04). Peak VO₂ improved (18.2 ± 4.2 vs. 20.9 ± 3.8 mL/min/kg^-1 , P = 0.05). Higher peak VO₂ at anaerobic threshold was associated with higher blood ferritin, reflecting higher metabolic exercise capacity after therapy (r = 0.9, P = 0.0009). Increase in EC was associated with haemoglobin increase (r = 0.7, P = 0.034). LV iron increased by 25.4% (48.5 [36.2; 64.8] vs. 36.2 [32.9; 41.9] ms, P < 0.04). Spleen and liver iron increased by 46.4 and 18.2%, respectively (71.8 [66.4; 93.1] vs. 38.5 [22.4; 76.9] ms, P < 0.04 and 33.5 ± 5.9 vs. 27.4 ± 8.6 ms, P < 0.007). Iron in skeletal muscle, brain, intestine, and bone marrow remained unchanged (29.6 [28.6; 31.2] vs. 30.4 [29.7; 30.7] ms, P = 0.7, 81.0 ± 6.3 vs. 82.9 ± 9.9 ms, P = 0.6, 34.3 ± 21.4 vs. 25.3 ± 14.1 ms, P = 0.2, 9.4 [7.5; 21.8] vs. 10.3 [6.7; 15.7] ms, P = 0.5 and 9.8 ± 1.5 vs. 13.7 ± 8.9 ms, P = 0.1).

CONCLUSIONS

CHF patients with ID showed lower spleen, liver, and in trend lower cardiac septal iron. After IVIT, iron signal of the left ventricle as well as spleen and liver increased. Improvement in EC was associated with increase in haemoglobin after IVIT. In ID, liver, spleen, and brain but not heart iron were associated with markers of systemic ID.

Iron and the Pathophysiology of Diabetes

High iron is a risk factor for type 2 diabetes mellitus (T2DM) and affects most of its cardinal features: decreased insulin secretion, insulin resistance, and increased hepatic gluconeogenesis. This is true across the normal range of tissue iron levels and in pathologic iron overload. Because of iron's central role in metabolic processes (e.g., fuel oxidation) and metabolic regulation (e.g., hypoxia sensing), iron levels participate in determining metabolic rates, gluconeogenesis, fuel choice, insulin action, and adipocyte phenotype. The risk of diabetes related to iron is evident in most or all tissues that determine diabetes phenotypes, with the adipocyte, beta cell, and liver playing central roles. Molecular mechanisms for these effects are diverse, although there may be integrative pathways at play. Elucidating these pathways has implications not only for diabetes prevention and treatment, but also for the pathogenesis of other diseases that are, like T2DM, associated with aging, nutrition, and iron.

A multivariate analysis of the risk of iron deficiency in plateletpheresis donors based on logistic regression

BACKGROUND

The purpose of this study was to analyze the application of individual factors, blood cell related indicators, and blood donation frequency in predicting the risk of iron deficiency of plateletpheresis donors.

METHODS

A total of 801 plateletpheresis donors were included in this study. The relationship between risk factors and iron deficiency was retrospectively analyzed by univariate analysis and logistic regression analysis. The application of Hb, MCHC, RDW-CV and blood donation frequency combined prediction of iron deficiency risk among plateletpheresis donors was evaluated.

RESULT

The rate of iron deficiency in this study was 31.5 % (241/766). The age, gender (the ratio of male donors), red blood cell related indicators, blood donation frequency were statistically different between the normal and iron deficiency group (all P < 0.05). Age, gender, the reciprocal of Hb and MCHC, RDW-CV, total number of blood donation and number of plateletpheresis donation in the past year, these indicators to predict the risk of iron deficiency area under the curve (AUC) were 0.558, 0.672, 0.785, 0.717, 0.599, 0.621, 0.646, respectively. The AUC of these indicators combined to predict the risk of iron deficiency was 0.877, higher than all single indicators. The sensitivity and specificity of these indicators combined in prediction of iron deficiency were 88.89 % and 81.57 %, respectively.

CONCLUSION

Age, gender, the reciprocal of Hb and MCHC, RDV-CV, blood donation frequency are associated with the risk of iron deficiency in plateletpheresis donors. The combination of these indicators has high value in predicting the risk of iron deficiency.

Influence of Different Obstetric Factors on Early Postpartum Pelvic Floor Function in Primiparas After Vaginal Delivery

Purpose

This study sought to explore the obstetric factors affecting early postpartum pelvic floor function of primiparas after vaginal delivery.

Patients and Methods

We included 3362 primiparas who underwent postpartum re-examination in International Peace Maternity and Child Health Hospital at 42-60 days after delivery. The Glazer Protocol was used to evaluate their pelvic floor function, and univariate and multivariate logistic regression analyses were performed to identify obstetric factors that might affect it.

Results

Forceps-assisted delivery significantly increased the risk of the decline in fast- and slow-twitch muscle strength in the early postpartum period when compared with natural vaginal delivery (P < 0.05). Women with a pre-pregnancy body mass index (BMI) of ≥18.5 kg/m² had a decreased risk of decline in fast-twitch muscle strength than those with a pre-pregnancy BMI of <18.5 kg/m² (P < 0.05). Women who had a pre-pregnancy BMI of 24.0 to <28.0 kg/m² bore a decreased risk of decline in slow-twitch muscle strength than those with a pre-pregnancy BMI of <18.5 kg/m² (P < 0.05). The risk of decline in fast-twitch muscle strength and slow-twitch muscle in women with anemia during pregnancy was significantly increased (P < 0.05); women with second-stage labors of >2 h had an increased risk of fast-twitch and slow-twitch muscle strength decline than those with <2 h (P < 0.05).

Conclusion

Both pre-pregnancy underweight and obesity may cause impairment of early postpartum pelvic floor function. Forceps delivery, anemia during pregnancy, and the length of second stage of labor are independent factors leading to pelvic floor function impairment.

Systematic review and meta-analysis of intravenous iron therapy for adults with non-anaemic iron deficiency: An abridged Cochrane review

Iron is an essential nutrient for oxygen supply and aerobic metabolism. Iron deficiency impacts cellular respiration and mitochondrial energy metabolism, which can lead to reduced skeletal muscle function and muscle mass, causing sarcopenia. Intravenous iron offers the ability to rapidly correct iron deficiency, but the functional impact on patient mental and physical health is unclear. We assessed the effects of intravenous iron therapy on physical function and quality of life in the treatment of adults with non-anaemic iron deficiency. An update and reanalysis of a previously published Cochrane systematic review was performed to assess randomized controlled trials that compared any intravenous iron preparation with placebo in adults. The primary functional outcome measure was physical performance as defined by the trial authors. Secondary outcome measures included fatigue and quality-of-life scores, and adverse effects at the end of follow-up. Biochemical efficacy was assessed by change in serum ferritin and haemoglobin concentration levels. Twenty-one randomized controlled trials, comprising 3514 participants, were included. Intravenous iron compared with placebo resulted in significantly increased physical function measured by mean peak oxygen consumption (mean difference [MD] 1.77 mL/kg/min, 95% confidence interval [CI] 0.57 to 2.97). An overall improvement in fatigue was seen (standardized MD 0.30, 95% CI -0.52 to -0.09) but no overall difference in quality of life (MD 0.15, 95% CI -0.01 to 0.31). Biochemically, intravenous iron resulted in improved serum ferritin (MD 245.52 μg/L, 95% CI 152.1 to 338.9) and haemoglobin levels (MD 4.65 g/L, 95% CI 2.53 to 6.78). There was a higher risk of developing mild adverse events in the intravenous iron group compared with the placebo group (risk ratio 1.77, 95% CI 1.10 to 2.83); however, no differences were seen in serious adverse events (risk difference 0, 95% CI -0.01 to 0.01). The quality of evidence was rated 'low' and 'very low' for all outcome variables, except for fatigue, mainly due to most studies being judged as having a high risk of bias. In non-anaemic iron-deficient adults, the use of intravenous iron compared with placebo improved physical function and reduced fatigue scores. However, we remain uncertain about the efficacy in this population due to low-quality evidence, and there is a need for further studies to address potential impact on overall quality of life.

Relative Handgrip Strength Mediates the Relationship between Hemoglobin and Health-Related Quality of Life in Older Korean Adults

Background: Little is known regarding how anemia and handgrip strength influence the health-related quality of life (HRQoL) of older populations. This population-based study aimed to examine whether handgrip strength mediates the association between anemia and HRQoL in a representative sample of 6892 Korean adults aged ≥ 65 years (3753 females). Methods: HRQoL was assessed with the EuroQol-5 dimension. Anemia was defined according to World Health Organization (WHO) criteria, and handgrip strength was measured with a digital hand dynamometer. Results: Individuals with anemia were at increased risk for a lower HRQoL (odds ratio, OR = 1.285, p = 0.002) even after adjustment for age, sex, body mass index, income, marital status, education, physical activity, and multimorbidity compared with individuals without anemia (OR = 1). Individuals with weak handgrip strength were also at increased risk for a lower HRQoL (OR = 1.429, p < 0.001) even after adjustment for all the covariates compared with individuals with normal handgrip strength (OR = 1). Mediation analysis with a bootstrapping procedure showed that relative handgrip strength mediated the relationship between hemoglobin and HRQoL (95% confidence interval, CI 0.0192 to 0.0289) even after adjustment for all covariates, with 42.0% of the total effect of hemoglobin on HRQoL explained. Conclusions: The current findings suggest that the impact of anemia on HRQoL is partially mediated by weak handgrip strength, implying the clinical importance of having or maintaining adequate hemoglobin and handgrip strength via healthy lifestyle choices to maintain a high HRQoL later in life.

Intravenous Iron Replacement Improves Exercise Tolerance in COPD: A Single-Blind Randomized Trial

INTRODUCTION

Iron deficiency affects exercise capacity because of the critical role iron plays in the optimal functioning of skeletal muscle metabolism. We hypothesized that intravenous iron may improve exercise tolerance, quality of life (QoL), and daily physical activity (DPA) in patients with chronic obstructive pulmonary disease (COPD).

METHODS

This was a placebo-controlled, single-blind, parallel-group, randomized clinical trial. Iron deficiency was defined as a ferritin level<100ng/mL or a ferritin level between 100 and 299ng/mL with a transferrin saturation<20%, with or without mild anaemia. Patients were randomized at a 2:1 ratio to receive intravenous ferric carboxymaltose or placebo. The primary objective was to investigate whether intravenous iron replacement improved endurance time from baseline by at least 33%. The secondary objectives were to evaluate impact on QoL using the COPD Assessment Test (CAT) and on DPA by accelerometry.

RESULTS

We included 66 patients, 44 (66.7%) in the intervention group and 22 (33.3%) in the placebo group. Among patients receiving ferric carboxymaltose, 23 (52.3%) achieved the primary endpoint compared to 4 (18.2%) in the placebo group [p=0.009; relative risk 3.12, (95% CI, 1.19-8.12)]. CAT score decreased -3 (-6.0-1.3) points from baseline in the intervention group (p=0.007), in contrast to placebo group [-1 (-4.0-2.3) points, p=0.236] with no differences in DPA and adverse events in both groups.

CONCLUSIONS

Iron replacement improved exercise capacity and QoL in stable COPD patients with iron deficiency. The treatment was well tolerated.

CLINICAL TRIAL REGISTRATION

EudraCT 2016-001238-89.

A Novel Muscle Atrophy Mechanism: Myocyte Degeneration Due to Intracellular Iron Deprivation

Muscle atrophy is defined as the progressive degeneration or shrinkage of myocytes and is triggered by factors such as aging, cancer, injury, inflammation, and immobilization. Considering the total amount of body iron stores and its crucial role in skeletal muscle, myocytes may have their own iron regulation mechanism. Although the detrimental effects of iron overload or iron deficiency on muscle function have been studied, the molecular mechanism of iron-dependent muscle atrophy has not been elucidated. Using human muscle tissues and in the mouse rotator cuff tear model, we confirmed an association between injury-induced iron depletion in myocytes and muscle atrophy. In differentiated C2C12 myotubes, the effects of iron deficiency on myocytes and the molecular mechanism of muscle atrophy by iron deficiency were evaluated. Our study revealed that the lower iron concentration in injured muscle was associated with the upregulation of ferroportin, an iron exporter that transports iron out of cells. Ferroportin expression was increased by hypoxia-inducible factor 1α (HIF1α), which is activated by muscle injury, and its expression is controlled by HIF1 inhibitor treatment. Iron deprivation caused myocyte loss and a marked depletion of mitochondrial membrane potential leading to muscle atrophy, together with increased levels of myostatin, the upstream regulator of atrogin1 and muscle RING-finger protein-1 (MuRF1). Myostatin expression under iron deficiency was mediated by an orphan nuclear receptor, dosage-sensitive sex reversal-adrenal hypoplasia congenita critical region on the X chromosome (DAX1).

The effect of intravenous iron supplementation on exercise capacity in iron-deficient but not anaemic patients with chronic kidney disease: study design and baseline data for a multicentre prospective double-blind randomised controlled trial

BACKGROUND

Many people living with chronic kidney disease (CKD) are iron deficient, even though they may not be anaemic. The Iron and Muscle study aims to evaluate whether iron supplementation reduces symptoms of fatigue, improves muscle metabolism, and leads to enhanced exercise capacity and physical function. We report here the trial design and baseline characteristics.

METHODS

This is a prospective, double-blind multicentre randomised controlled trial (RCT) including 75 non-dialysis stage 3-4 CKD patients with iron deficiency but without anaemia. Patients were randomly (1:1) assigned to either: i) intravenous iron therapy, or ii) placebo, with concurrent recruitment of eight CKD non-iron deficient participants and six healthy volunteers. The primary outcome of the study is the six-minute walk test (6MWT) distance between baseline and four-weeks. An additional exercise training programme for patients in both groups was initiated and completed between 4 and 12 weeks, to determine the effect of iron repletion compared to placebo treatment in the context of patients undertaking an exercise programme. Additional secondary outcomes include fatigue, physical function, muscle strength, muscle metabolism, quality of life, resting blood pressure, clinical chemistry, safety and harms associated with the iron therapy intervention and the exercise training intervention, and hospitalisations. All outcomes were conducted at baseline, 4, and 12 weeks, with a nested qualitative study, to investigate the experience of living with iron deficiency and intervention acceptability. The cohort have been recruited and baseline assessments undertaken.

RESULTS

Seventy-five individuals were recruited. 44% of the randomised cohort were male, the mean (SD) age was 58 (14) years, and 56% were White. Body mass index was 31 (7) kg/m²; serum ferritin was 59 (45) μg/L, transferrin saturation was 22 (10) %, and haemoglobin was 125 (12) g/L at randomisation for the whole group. Estimated glomerular filtration rate was 35 (12) mL/min/1.73 m² and the baseline 6MWT distance was 429 (174) m.

CONCLUSION

The results from this study will address a substantial knowledge gap in the effects of intravenous iron therapy, and offer potential clinical treatment options, to improve exercise capacity, physical function, fatigue, and muscle metabolism, for non-dialysis patients with CKD who are iron-deficient but not anaemic. It will also offer insight into the potential novel effects of an 8-week exercise training programme.

TRIAL REGISTRATION

EudraCT: 2018-000,144-25 Registered 28/01/2019.

Oral iron supplementation in patients with heart failure: a systematic review and meta-analysis

AIMS

This review aimed to assess whether oral iron supplementation in a chronic heart failure (HF) population with iron deficiency (ID) or mild anaemia is safe and effective according to evidence-based medicine.

METHODS

We retrieved 1803 records from the PubMed, Embase, and the Cochrane Library databases from 1 January 1991 to 15 September 2021. The clinical outcome of oral iron supplementation for ID anaemia in patients with HF was the primary endpoint. The primary safety measures included adverse events and all-cause mortality, and efficacy measures included transferrin saturation (Tsat), ferritin levels, and the 6-min walk test (6MWT). The rate ratio (RR) was used to pool the efficacy measures.

RESULTS

Five randomized controlled trials that compared oral iron treatment for patients with the placebo group and included a combined total of 590 participants were analysed. No significant difference was found in all-cause death between oral iron treatment and placebo groups (RR = 0.77; 95% confidence intervals (CI), 0.46-1.29, Z = 0.98; P = 0.33). However, adverse events were not significantly higher in the iron treatment group (RR = 0.83; 95% CI, 0.60-1.16, Z = 1.07; P = 0.28). In addition, ferritin levels and Tsat were slightly increased after iron complex administration in patients with HF but were not statistically significant (ferritin: mean difference [MD] = 2.70, 95% CI, -2.41 to 7.81, Z = 1.04; P = 0.30; Tsat: MD = 27.42, 95% CI, -4.93 to 59.78, Z = 1.66; P = 0.10). No significant difference was found in exercise capacity, as indicated by the 6MWT results (MD = 59.60, 95% CI, -17.89 to 137.08, Z = 1.51; P = 0.13). We also analysed two non-randomized controlled trials with follow-up results showing that oral iron supplementation increased serum iron levels (MD = 28.87, 95% CI, 1.62-56.12, Z = 2.08; P = 0.04).

CONCLUSIONS

Based on the current findings, oral iron supplementation can increase serum iron levels in patients with HF and ID or mild anaemia but does not improve Tsat and 6MWT. In addition, oral iron supplementation is relatively safe.

Does the TMPRSS6 C > T Polymorphism Modify the Endurance Training Effects on Hematological Parameters?

This study investigated the role of TMPRSS6 C > T polymorphism (TMPRP) on the effects of chronic aerobic training on main hematological parameters in male soccer referees, which is yet unknown. Two groups composed of total of 45 healthy male soccer referees and 42 sedentary were compared for hemogram, serum hepcidin, ferritin, and iron levels. TMPRP was determined from genomic DNA samples. Participants' physical and physiological (Yoyo endurance level-2 test) measurements were carried out. The athletic T carrier (Tc = TT + TC) group RBC count was significantly higher than the control (p < 0.01), whereas the athletic CC homozygous group serum iron and transferrin saturation (TS) were lower than the control depending on the TMPRP. The ferritin and iron values of the athletic Tc group were higher than of the athletic CC group (29.2% and 14.1%, respectively; p > 0.05) although the control Tc group RBC (p < 0.05) and iron (23.8%, p > 0.05) values were lower than the control CC due to genetic tendency. The training did not change hepcidin levels. These results suggest that the TMPRP can modify the endurance training effects on iron and TS levels and RBC count (in the CC and Tc groups) respectively. The CC group may be adversely affected for iron and TS from endurance trainings. It may be recommended that the training programs should be organized according to phenotype characteristics.

Practical Guidance for Diagnosing and Treating Iron Deficiency in Patients with Heart Failure: Why, Who and How?

Iron deficiency (ID) is a comorbid condition frequently seen in patients with heart failure (HF). Iron has an important role in the transport of oxygen, and is also essential for skeletal and cardiac muscle, which depend on iron for oxygen storage and cellular energy production. Thus, ID per se, even without anaemia, can be harmful. In patients with HF, ID is associated with a poorer quality of life (QoL) and exercise capacity, and a higher risk of hospitalisations and mortality, even in the absence of anaemia. Despite its negative clinical consequences, ID remains under-recognised. However, it is easily diagnosed and managed, and the recently revised 2021 European Society of Cardiology (ESC) guidelines on HF provide specific recommendations for its diagnosis and treatment. Prospective randomised controlled trials in patients with symptomatic HF with reduced ejection fraction (HFrEF) show that correction of ID using intravenous iron (principally ferric carboxymaltose [FCM]) provides improvements in symptoms of HF, exercise capacity and QoL, and a recent trial demonstrated that FCM therapy following hospitalisation due to acute decompensated HF reduced the risk of subsequent HF hospitalisations. This review provides a summary of the epidemiology and pathophysiology of ID in HFrEF, and practical guidance on screening, diagnosing, and treating ID.

Changes in dietary total and non-haem iron intake is associated with incident frailty in older men: The Concord Health and Ageing in Men Project

Background

Nutritional intake could influence the development of frailty. The aim was to evaluate the associations between dietary iron intakes and changes in dietary iron intakes with frailty.

Methods

Cross-sectional analyses involved 785 men with Fried frailty phenotype (FP) and 758 men with Rockwood frailty index (FI) data aged 75 years and older at nutrition assessment from the Concord Health and Ageing in Men Project prospective cohort study. Of these, 563 men who were FP robust or prefrail, and 432 men who were FI nonfrail were included in the longitudinal analyses for more than 3 years. Dietary intake was assessed at both timepoints using a validated diet history questionnaire. The dietary calculation was used to derive heme iron and nonheme iron intakes from total iron intakes. The associations were evaluated through binary logistic regression.

Results

Incidence of FP frailty was 15.3% (n = 86). In longitudinal analyses, maintaining total iron intakes (medium tertile −2.61–0.81 mg/d), increases in total iron and nonheme iron intakes (high tertiles ≥0.82 mg/d and ≥0.80 mg/d), and changes in nonheme iron intake (1 mg increment) were associated with reduced risks of incident FP frailty (OR: 0.47 [95% confindence interval (CI): 0.24, 0.93, p = .031], OR 0.48 [95% CI: 0.23, 0.99, p = .048], OR 0.41 [95% CI: 0.20, 0.88, p = .022], and OR 0.89 [95% CI: 0.82, 0.98, p = .017]).

Conclusion

Maintaining or increases in total dietary iron and increases or changes in dietary nonheme iron intakes more than 3 years were associated with reduced incidence of FP frailty in older men.

Deficiência de Ferro na Insuficiência Cardíaca com Fração de Ejeção Reduzida: Fisiopatologia, Diagnóstico e Tratamento

A deficiência de ferro (DF) ou ferropenia é uma importante comorbidade na insuficiência cardíaca com fração de ejeção reduzida (ICFER) estável, e muito prevalente tanto nos anêmicos como não anêmicos. A ferropenia na ICFER deve ser pesquisada por meio da coleta de saturação de transferrina e ferritina. Há dois tipos de ferropenia na IC: absoluta, em que as reservas de ferro estão depletadas; e funcional, onde o suprimento de ferro é inadequado apesar das reservas normais. A ferropenia está associada com pior classe funcional e maior risco de morte em pacientes com ICFER, e evidências científicas apontam melhora de sintomas e de qualidade de vida desses pacientes com tratamento com ferro parenteral na forma de carboximaltose férrica. O ferro exerce funções imprescindíveis como o transporte (hemoglobina) e armazenamento (mioglobina) de oxigênio, além de ser fundamental para o funcionamento das mitocôndrias, constituídas de proteínas à base de ferro, e local de geração de energia na cadeia respiratória pelo metabolismo oxidativo. A geração insuficiente e utilização anormal de ferro nas células musculares esquelética e cardíaca contribuem para a fisiopatologia da IC. A presente revisão tem o objetivo de aprofundar o conhecimento a respeito da fisiopatologia da ferropenia na ICFER, abordar as ferramentas disponíveis para o diagnóstico e discutir sobre a evidência científica existente de reposição de ferro.

Total iron binding capacity is a predictor for muscle loss in maintenance hemodialysis patients

BACKGROUND

Protein-energy wasting in hemodialysis (HD) patients is characterized by decreased skeletal muscle mass and plasma protein. Some previous studies reported relationships between skeletal muscle dysfunction and iron deficiency. Dialysis patients with malnutrition may have a functional iron deficiency (FID) because of inflammation. Serum total iron binding capacity (TIBC), correlated with transferrin, is a nutritional status marker in HD patients and a biomarker of iron status. The relationship between muscle loss and iron status is unknown. The aim of the present study was to assess the relationship between iron status and change in skeletal muscle mass.

METHODS

A prospective cohort of 267 HD patients was examined for 12 months. Blood samples were obtained at baseline to measure TIBC, ferritin, transferrin saturation (TSAT), and hepcidin-25. Nutritional status and changes in muscle mass were assessed by subjective global assessment, albumin, creatinine index, and percentage creatinine generation rate.

RESULTS

At baseline, lower tertiles of TIBC were significantly related to lower muscle mass and albumin levels; they were also significantly correlated with high ferritin, hepcidin-25, and TSAT levels, as well as a higher proportion of use of erythropoiesis-stimulating agents. Multiple regression analysis adjusted with confounders showed TIBC was an independent biomarker for decreased muscle mass and albumin. Change in muscle mass remained significantly decreased in the lower tertile of TIBC and in malnourished patients.

CONCLUSIONS

The present study demonstrated relationships between FID and muscle loss. TIBC was an independent biomarker of muscle loss in HD patients, considering iron status, inflammation, oxidative stress, and malnutrition.

2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: Developed by the Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC). With the special contribution of the Heart Failure Association (HFA) of the ESC

Document Reviewers: Rudolf A. de Boer (CPG Review Coordinator) (Netherlands), P. Christian Schulze (CPG Review Coordinator) (Germany), Magdy Abdelhamid (Egypt), Victor Aboyans (France), Stamatis Adamopoulos (Greece), Stefan D. Anker (Germany), Elena Arbelo (Spain), Riccardo Asteggiano (Italy), Johann Bauersachs (Germany), Antoni Bayes-Genis (Spain), Michael A. Borger (Germany), Werner Budts (Belgium), Maja Cikes (Croatia), Kevin Damman (Netherlands), Victoria Delgado (Netherlands), Paul Dendale (Belgium), Polychronis Dilaveris (Greece), Heinz Drexel (Austria), Justin Ezekowitz (Canada), Volkmar Falk (Germany), Laurent Fauchier (France), Gerasimos Filippatos (Greece), Alan Fraser (United Kingdom), Norbert Frey (Germany), Chris P. Gale (United Kingdom), Finn Gustafsson (Denmark), Julie Harris (United Kingdom), Bernard Iung (France), Stefan Janssens (Belgium), Mariell Jessup (United States of America), Aleksandra Konradi (Russia), Dipak Kotecha (United Kingdom), Ekaterini Lambrinou (Cyprus), Patrizio Lancellotti (Belgium), Ulf Landmesser (Germany), Christophe Leclercq (France), Basil S. Lewis (Israel), Francisco Leyva (United Kingdom), AleVs Linhart (Czech Republic), Maja-Lisa Løchen (Norway), Lars H. Lund (Sweden), Donna Mancini (United States of America), Josep Masip (Spain), Davor Milicic (Croatia), Christian Mueller (Switzerland), Holger Nef (Germany), Jens-Cosedis Nielsen (Denmark), Lis Neubeck (United Kingdom), Michel Noutsias (Germany), Steffen E. Petersen (United Kingdom), Anna Sonia Petronio (Italy), Piotr Ponikowski (Poland), Eva Prescott (Denmark), Amina Rakisheva (Kazakhstan), Dimitrios J. Richter (Greece), Evgeny Schlyakhto (Russia), Petar Seferovic (Serbia), Michele Senni (Italy), Marta Sitges (Spain), Miguel Sousa-Uva (Portugal), Carlo G. Tocchetti (Italy), Rhian M. Touyz (United Kingdom), Carsten Tschoepe (Germany), Johannes Waltenberger (Germany/Switzerland) All experts involved in the development of these guidelines have submitted declarations of interest. These have been compiled in a report and published in a supplementary document simultaneously to the guidelines. The report is also available on the ESC website www.escardio.org/guidelines For the Supplementary Data which include background information and detailed discussion of the data that have provided the basis for the guidelines see European Heart Journal online.

Iron Deficiency in Heart Failure: Mechanisms and Pathophysiology

Iron is an essential micronutrient for a myriad of physiological processes in the body beyond erythropoiesis. Iron deficiency (ID) is a common comorbidity in patients with heart failure (HF), with a prevalence reaching up to 59% even in non-anaemic patients. ID impairs exercise capacity, reduces the quality of life, increases hospitalisation rate and mortality risk regardless of anaemia. Intravenously correcting ID has emerged as a promising treatment in HF as it has been shown to alleviate symptoms, improve quality of life and exercise capacity and reduce hospitalisations. However, the pathophysiology of ID in HF remains poorly characterised. Recognition of ID in HF triggered more research with the aim to explain how correcting ID improves HF status as well as the underlying causes of ID in the first place. In the past few years, significant progress has been made in understanding iron homeostasis by characterising the role of the iron-regulating hormone hepcidin, the effects of ID on skeletal and cardiac myocytes, kidneys and the immune system. In this review, we summarise the current knowledge and recent advances in the pathophysiology of ID in heart failure, the deleterious systemic and cellular consequences of ID.

Additional burden of iron deficiency in heart failure patients beyond the cardio-renal anaemia syndrome: findings from the BIOSTAT-CHF study

Aims

Whereas the combination of anaemia and chronic kidney disease (CKD) has been extensively studied in patients with heart failure (HF), the contribution of iron deficiency (ID) to this dysfunctional interplay is unknown. We aimed to assess clinical associates and pathophysiological pathways related to ID in this multimorbid syndrome.

Methods and results

We studied 2151 patients with HF from the BIOSTAT‐CHF cohort. Patients were stratified based on ID (transferrin saturation <20%), anaemia (World Health Organization definition) and/or CKD (estimated glomerular filtration rate <60 ml/min/1.73 m²). Patients were mainly men (73.3%), with a median age of 70.5 (interquartile range 61.4–78.1). ID was more prevalent than CKD and anaemia (63.3%, 47.2% and 35.6% respectively), with highest prevalence in those with concomitant CKD and anaemia (77.5% vs. 59.3%; p < 0.001). There was a considerable overlap in biomarkers and pathways between patients with isolated ID, anaemia or CKD, or in combination, with processes related to immunity, inflammation, cell survival and cancer amongst the common pathways. Key biomarkers shared between syndromes with ID included transferrin receptor, interleukin‐6, fibroblast growth factor‐23, and bone morphogenetic protein 6. Having ID, either alone or on top of anaemia and/or CKD, was associated with a lower overall summary Kansas City Cardiomyopathy Questionnaire score, an impaired 6‐min walk test and increased incidence of hospitalizations and/or mortality in multivariable analyses (all p < 0.05).

Conclusion

Iron deficiency, CKD and/or anaemia in patients with HF have great overlap in biomarker profiles, suggesting common pathways associated with these syndromes. ID either alone or on top of CKD and anaemia is associated with worse quality of life, exercise capacity and prognosis of patients with worsening HF.

Iron Deficiency: A New Target for Patients With Heart Failure

Iron deficiency (ID) is one of the most frequent comorbidities in patients with heart failure (HF). ID is estimated to be present in up to 50% of outpatients and is a strong independent predictor of HF outcomes. ID has been shown to reduce quality of life, exercise capacity and survival, in both the presence and absence of anemia. The most recent 2016 guidelines recommend starting replacement treatment at ferritin cutoff value <100 mcg/l or between 100 and 299 mcg/l when the transferrin saturation is <20%. Beyond its effect on hemoglobin, iron plays an important role in oxygen transport and in the metabolism of cardiac and skeletal muscles. Mitochondria are the most important sites of iron utilization and energy production. These factors clearly have roles in the diminished exercise capacity in HF. Oral iron administration is usually the first route used for iron repletion in patients. However, the data from the IRONOUT HF study do not support the use of oral iron supplementation in patients with HF and a reduced ejection fraction, because this treatment does not affect peak VO₂ (the primary endpoint of the study) or increase serum ferritin levels. The FAIR-HF and CONFIRM-HF studies have shown improvements in symptoms, quality of life and functional capacity in patients with stable, symptomatic, iron-deficient HF after the administration of intravenous iron (i.e., FCM). Moreover, they have shown a decreased risk of first hospitalization for worsening of HF, as later confirmed in a subsequent meta-analysis. In addition, the EFFECT-HF study has shown an improvement in peak oxygen consumption at CPET (a parameter generally considered the gold standard of exercise capacity and a predictor of outcome in HF) in patients randomized to receive ferric carboxymaltose. Finally, the AFFIRM AHF trial evaluating the effects of FCM administration on the outcomes of patients hospitalized for acute HF has found significantly fewer hospital readmissions due to HF among patients treated with FCM rather than placebo.

Cadmium Accumulation and Depuration in the Muscle of Prussian Carp (Carassius gibelio Bloch) after Sub-Chronic Cadmium Exposure: Ameliorating Effect of Melatonin

Simple Summary

Rapid urbanization and industrialization has resulted in substantial contamination of various ecosystems, especially aquatic environments with heavy metals. Heavy metals are classified as either essential (iron, zinc, or copper) or non-essential (cadmium, lead, or mercury) for organisms. Cadmium is a toxic, cancerogenic, and mutagenic metal, occurring as anthropogenic contamination in aquatic environments. The level of cadmium uptake in animals depends on the rate at which they are accumulated and eliminated. Exceeding the permissible levels of cadmium in fish muscle may pose risks for human health in the case of contaminated fish consumption. The aim of the present study was to evaluate the influence of melatonin on cadmium accumulation and elimination in fish muscle. Prussian carps were exposed to two doses of cadmium in the presence or without the melatonin implants. This is the first study to report that melatonin co-administration can effectively protect fish from the accumulation of cadmium in muscle tissue, improve the accumulated cadmium depuration from muscle, and prevent disturbance of the concentration of essential metals in fish body.

Abstract

The aim of this study was to investigate the bioaccumulation of cadmium in the muscle tissue of Prussian carp during 7 and 13 weeks of exposure to different concentrations of this metal in water (0.4 and 4.0 mg/L), and the depuration of cadmium from muscle during the following 6-week depuration period in the presence of melatonin implants. Furthermore, the relationship between cadmium accumulation and the levels of essential bioelements (copper, zinc, iron) in muscle was evaluated, as well as the bioconcentration factor of cadmium. Heavy metal concentration was determined using atomic absorption spectrometry. Cadmium accumulation in fish muscle increased with the duration of exposure. Cd concentrations exceeded the permissible levels for human consumption in groups exposed to the higher concentration of this metal. Moreover, a significant increase of Zn and Fe levels in the muscle was observed. In the fish that received melatonin implants and were exposed to Cd, its level in the muscle was significantly lower. The depuration of accumulated cadmium depended mainly on the duration of the elimination period. This is the first study to report that melatonin co-administration can effectively protect the fish from the accumulation of cadmium in muscle tissue and changes in trace metal levels.

New Drugs for Heart Failure: What is the Evidence in Older Patients?

Heart failure (HF) is a major public health concern, with a high prevalence in the older population. The majority of randomized clinical trials evaluating new emerging pharmacologic agents for HF (eg, angiotensin receptor-neprilysin inhibitors, sodium-glucose cotransporter 2 inhibitors, intravenous iron for deficiency treatment, transthyretin stabilizers, soluble guanylate cyclase stimulators, cardiac myosin activators, and new potassium binders) have found positive results on various clinical outcomes, particularly in patients with reduced ejection fraction. These treatments might have an important role in the management of older patients as well. Nevertheless, trials demonstrating benefit of these drugs have involved patients significantly younger (on average, approximately 10 years) and fewer comorbidities than those commonly encountered in clinical practice. We describe the recent evidence regarding the newest HF drugs and their applicability to older individuals in terms of efficacy and safety, and we discuss their effects on outcomes particularly valuable to older patients, such as preservation of cognitive function, functional status, independence, and quality of life. Although available subgroup analyses seem to confirm efficacy and safety across the age spectrum for some of these drugs, their effects on older patients centered outcomes often have been neglected. Future HF trials should be designed to include older patients more representative of the real clinical practice, to overcome generalizability biases.

Heart failure with preserved ejection fraction based on aging and comorbidities

Heart failure (HF) with preserved ejection fraction (HFpEF) is a leading cause of hospitalizations and mortality when diagnosed at the age of ≥ 65 years. HFpEF represents multifactorial and multisystemic syndrome and has different pathophysiology and phenotypes. Its diagnosis is difficult to be established based on left ventricular ejection fraction and may benefit from individually tailored approaches, underlying age-related changes and frequent comorbidities. Compared with the rapid development in the treatment of heart failure with reduced ejection fraction, HFpEF presents a great challenge and needs to be addressed considering the failure of HF drugs to improve its outcomes. Further extensive studies on the relationships between HFpEF, aging, and comorbidities in carefully phenotyped HFpEF subgroups may help understand the biology, diagnosis, and treatment of HFpEF. The current review summarized the diagnostic and therapeutic development of HFpEF based on the complex relationships between aging, comorbidities, and HFpEF.

Intravenous iron and chronic obstructive pulmonary disease: a randomised controlled trial

Background

Increased iron availability modifies cardiorespiratory function in healthy volunteers and improves exercise capacity and quality of life in patients with heart failure or pulmonary hypertension. We hypothesised that intravenous iron would produce improvements in oxygenation, exercise capacity and quality of life in patients with chronic obstructive pulmonary disease (COPD).

Methods

We performed a randomised, placebo-controlled, double-blind trial in 48 participants with COPD (mean±SD: age 69±8 years, haemoglobin 144.8±13.2 g/L, ferritin 97.1±70.0 µg/L, transferrin saturation 31.3%±15.2%; GOLD grades II–IV), each of whom received a single dose of intravenous ferric carboxymaltose (FCM; 15 mg/kg bodyweight) or saline placebo. The primary endpoint was peripheral oxygen saturation (SpO₂) at rest after 1 week. The secondary endpoints included daily SpO₂, overnight SpO₂, exercise SpO₂, 6 min walk distance, symptom and quality of life scores, serum iron indices, spirometry, echocardiographic measures, and exacerbation frequency.

Results

SpO₂ was unchanged 1 week after FCM administration (difference between groups 0.8%, 95% CI −0.2% to 1.7%). However, in secondary analyses, exercise capacity increased significantly after FCM administration, compared with placebo, with a mean difference in 6 min walk distance of 12.6 m (95% CI 1.6 to 23.5 m). Improvements of ≥40 m were observed in 29.2% of iron-treated and 0% of placebo-treated participants after 1 week (p=0.009). Modified MRC Dyspnoea Scale score was also significantly lower after FCM, and fewer participants reported scores ≥2 in the FCM group, compared with placebo (33.3% vs 66.7%, p=0.02). No significant differences were observed in other secondary endpoints. Adverse event rates were similar between groups, except for hypophosphataemia, which occurred more frequently after FCM (91.7% vs 8.3%, p<0.001).

Conclusions

FCM did not improve oxygenation over 8 weeks in patients with COPD. However, this treatment was well tolerated and produced improvements in exercise capacity and functional limitation caused by breathlessness. These effects on secondary endpoints require confirmation in future studies.

Trial registration number

ISRCTN09143837.

Iron supplementation regulates the progression of high fat diet induced obesity and hepatic steatosis via mitochondrial signaling pathways

Disruption of iron metabolism is closely related to metabolic diseases. Iron deficiency is frequently associated with obesity and hepatic steatosis. However, the effects of iron supplementation on obesity and energy metabolism remain unclear. Here we show that a high-fat diet supplemented with iron reduces body weight gain and hepatic lipid accumulation in mice. Iron supplementation was found to reduce mitochondrial morphological abnormalities and upregulate gene transcription involved in mitochondrial function and beta oxidation in the liver and skeletal muscle. In both these tissues, iron supplementation increased the expression of genes involved in heme or iron–sulfur (Fe–S) cluster synthesis. Heme and Fe–S cluster, which are iron prosthetic groups contained in electron transport chain complex subunits, are essential for mitochondrial respiration. The findings of this study demonstrated that iron regulates mitochondrial signaling pathways—gene transcription of mitochondrial component molecules synthesis and their energy metabolism. Overall, the study elucidates the molecular basis underlying the relationship between iron supplementation and obesity and hepatic steatosis progression, and the role of iron as a signaling molecule.

Anemia of Prematurity and Oral Feeding Milestones in Premature Infants

OBJECTIVE

Anemia of prematurity (AOP) and oral feeding problems are common in premature infants. This study aimed to determine the influence of AOP on aerodigestive outcomes and the duration to full Per Oral (PO).

STUDY DESIGN

Prospectively collected data on premature infants who initiated oral feeds at ≤ 34 weeks' postmenstrual age were examined. Infants were categorized into "AOP+" and "AOP-" based on hematocrit at initial PO, that is, < 29 or ≥ 29%.

RESULTS

Forty-four infants in AOP+ compared with 74 in AOP-. AOP+ infants had lower birth gestation and weight (p < 0.001). The anthropometrics at initial PO were similar. AOP+ had lower mean hematocrit and higher oxygen need at initial PO, and at full PO (p < 0.05). AOP+ reached full PO at a later gestation and took longer days from initial PO to full PO (p < 0.01). BPD, intraventricular hemorrhage (IVH ≤ 2), and hospital stay were greater in the AOP+ (p < 0.05). After adjusting for covariates, initial PO hematocrit was not predictive of time to full PO [hazard ratio 1.3 (CI 0.88-2.0), p = 0.18].

CONCLUSION

AOP is not independently associated with the duration to full PO. Supplemental oxygen for associated comorbidities may have compensated for the underlying anemia.

Intravenous Iron Treatment in the Prevention of Iron Deficiency and Anaemia After Roux-en-Y Gastric Bypass

Background

Iron absorption is disturbed after Roux-en-Y gastric bypass (RYGB) and iron deficiency with or without anaemia affects almost half of all patients. Intravenous iron is an option when per oral iron is insufficient or not tolerated. This study explores whether routinely offering intravenous iron treatment when iron stores are empty can prevent anaemia and iron deficiency after RYGB.

Methods

This is a study of prospectively registered data on clinical information, haematological tests and intravenous iron treatment from 644 RYGB patients who underwent surgery between 2004 and 2013, postoperatively followed more than 5 years. Intravenous iron treatment was offered to patients with ferritin ≤ 15 μg/L.

Results

Clinical information was available for all patients at baseline and for 553/644 patients at 5 years; laboratory results were available for 540/644 patients at baseline and 411/644 patients after 5 years. The mean age was 39.8 (± 9.7) years. Overall, 187/483 (38.7%) women and 9/161 (5.6%) men were given intravenous iron treatment in the observation period. From baseline to 5 years, mean haemoglobin decreased by 0.3 g/dL in both men and women. Anaemia occurred in 18/311 (5.8%) women and 9/100 (9%) men at 5 years. Depleted iron stores (ferritin ≤ 15 μg/L) were seen among 44/323(13.6%) women and 3/102 (2.9%) men, and low iron stores (ferritin 16–50 μg/L) occurred in 144/326 (44.6%) women and 38/102 (37.3%) men 5 years after RYGB.

Conclusion

By routinely offering intravenous iron treatment to patients with depleted iron stores after RYGB, haemoglobin levels were preserved. Half of the patients experienced low or depleted iron stores at 5 years.

Indirect comparison between ferric carboxymaltose and oral iron replacement in heart failure with reduced ejection fraction: a network meta-analysis

Treatment of iron deficiency (ID) in patients with heart failure (HF) has improved symptoms, quality of life, exercise capacity and has reduced hospitalizations in randomized controlled trials (RCTs) and meta-analyses. Intravenous ferric carboxymaltose (FCM) provided convincing results in this field, while oral iron supplementation failed. However, FCM and oral iron were compared to placebo, and a comparison between the two strategies is still lacking. We aimed to fill this gap of knowledge with an indirect comparison between them by means of a network meta-analysis of RCTs. Five studies measuring exercise capacity (i.e. 6-minute walking test) and quality of life (i.e. Kansas City Cardiomyopathy Questionnaire) were eligible to be included in our review. Given the limitations of a network meta-analysis, our findings support the better efficacy of FCM than oral iron as regards exercise capacity, with a trend towards an improvement in quality of life, suggesting that FCM seems to be strategy of choice to correct ID in HF patients.

Risk stratification and management of women with cardiomyopathy/heart failure planning pregnancy or presenting during/after pregnancy: a position statement from the Heart Failure Association of the European Society of Cardiology Study Group on Peripartum Cardiomyopathy

This position paper focusses on the pathophysiology, diagnosis and management of women diagnosed with a cardiomyopathy, or at risk of heart failure (HF), who are planning to conceive or present with (de novo or previously unknown) HF during or after pregnancy. This includes the heterogeneous group of heart muscle diseases such as hypertrophic, dilated, arrhythmogenic right ventricular and non-classified cardiomyopathies, left ventricular non-compaction, peripartum cardiomyopathy, Takotsubo syndrome, adult congenital heart disease with HF, and patients with right HF. Also, patients with a history of chemo-/radiotherapy for cancer or haematological malignancies need specific pre-, during and post-pregnancy assessment and counselling. We summarize the current knowledge about pathophysiological mechanisms, including gene mutations, clinical presentation, diagnosis, and medical and device management, as well as risk stratification. Women with a known diagnosis of a cardiomyopathy will often require continuation of drug therapy, which has the potential to exert negative effects on the foetus. This position paper assists in balancing benefits and detrimental effects.