Effect of iron supplementation in patients with heart failure and iron deficiency: A systematic review and meta-analysis

Sodium-Glucose Transporter 2 (SGLT2) Inhibitors and Iron Deficiency in Heart Failure and Chronic Kidney Disease: A Literature Review

Heart failure (HF) and chronic kidney disease (CKD) are associated with high mortality. In both disorders, impaired iron homeostasis, mostly in the form of a functional iron deficiency, is a frequent co-morbidity. In HF, functional iron deficiency and management by i.v. iron supplementation have been proven to affect both prognosis and functional capacity. In the same context, iron supplementation is routine for the adequate management of renal anemia in CKD. In numerous recent studies in HF and in CKD, sodium-glucose transporter 2 (SGLT2) inhibitor treatment has been proven to significantly reduce mortality. Furthermore, the same trials showed that these drugs alleviate iron deficiency and anemia. These effects of SGLT2 inhibitors may be due to an amelioration of inflammation with reduced interleukin-6 (IL-6) and to an enhancement of autophagy with increased sirtuin 1 (SIRT1), both associated with modified production of hepcidin and enhanced ferritinophagy. However, the exact pathogenic basis of the beneficial SGLT2 inhibitor action is not fully elucidated. Nevertheless, effects on iron homeostasis might be a potential explanatory mechanism for the powerful SGLT2 inhibitors' cardiovascular and renal outcome benefits. In addition, the interaction between iron supplementation and SGLT2 inhibitors and its potential impact on prognosis remains to be clarified by future studies. This review represents a significant effort to explore the complex relationships involved, seeking to elucidate the intricate mechanisms by which SGLT2 inhibitors influence iron homeostasis.

Cost-effective heart failure management: Meta-analysis of IV iron therapy in iron-deficient heart failure patients

Background

Iron deficiency is an important co-morbidity in heart failure patients. IV iron may improve quality of life and reduce heart failure hospitalizations, but the results of the clinical trials are varied.

Objective

The purpose of this meta-analysis is to assess not only the effect of IV iron in iron-deficient heart failure patients but also the quality of evidence.

Methods

PubMed and Cochrane databases were searched from inception to Oct 2021. Randomized clinical trials in iron-deficient, heart failure patients assessing the effect of IV iron versus placebo and with at least 12 weeks of follow-up were included. The outcomes were pooled and analyzed using a random-effect model. The quality of evidence was assessed using the GRADE approach.

Results

Seven studies were included in our meta-analysis. IV iron was associated with a 13.8 % decreased risk of HF hospitalizations (OR 0.59; 0.35-0.98, p = 0.040, GRADE = Low). All-cause mortality and CV mortality were not different between IV iron and placebo. But a composite outcome of HF hospitalizations or CV mortality was 17.5 % lower with IV iron (OR 0.51;0.31-0.84, p = 0.008, GRADE = Moderate).

Conclusions

Among heart failure patients with iron deficiency, IV iron is associated with lower HF hospitalizations. It is a relatively inexpensive regimen that can potentially improve quality of life and decrease healthcare expenditure.

Systematic review and meta-analysis of intravenous iron-carbohydrate complexes in HFrEF patients with iron deficiency

Iron deficiency (ID) is a common co-morbidity in patients with heart failure (HF). The present meta-analysis evaluates the effect of intravenous (IV) iron-carbohydrate complex supplementation in patients with HF with reduced ejection fraction (HFrEF) and ID/iron deficiency anaemia (IDA). Randomized controlled trials (RCTs) comparing IV iron-carbohydrate complexes with placebo/standard of care in patients with HFrEF with ID/IDA were identified using Embase (from 1957) and PubMed (from 1989) databases through 25 May 2021. Twelve RCTs including 2381 patients were included in this analysis. The majority (90.8%) of patients receiving IV iron-carbohydrate therapy were administered ferric carboxymaltose (FCM); 7.5% received iron sucrose and 1.6% received iron isomaltoside. IV iron-carbohydrate therapy significantly reduced hospitalization for worsening HF [0.53 (0.42-0.65); P < 0.0001] and first hospitalization for worsening HF or death [0.75 (0.59-0.95); P = 0.016], but did not significantly impact all-cause mortality, compared with control. IV iron-carbohydrate therapy significantly improved functional and exercise capacity compared with the control. There was no significant difference in outcome between IV iron-carbohydrate formulations when similar endpoints were measured. No significant difference in adverse events (AE) was observed between the treatment groups. IV iron-carbohydrate therapy resulted in improvements in a range of clinical outcomes and increased functional and exercise capacity, whereas AEs were not significantly different between IV iron-carbohydrate and placebo/standard of care arms. These findings align with the European Society of Cardiology's 2021 HF guidelines, which recommend the consideration of FCM in symptomatic patients with a left ventricular ejection fraction < 45% and ID.

Expression of Iron Metabolism Proteins in Patients with Chronic Heart Failure

In heart failure, iron deficiency is a common comorbid disease that negatively influences exercise tolerance, number of hospitalizations and mortality rate, and this is why iron iv supplementation is recommended. Little is known about the changes in iron-related proteins in the human HF myocardium. The purpose of this study was to assess iron-related proteins in non-failing (NFH) vs. failing (FH) human myocardium. The study group consisted of 58 explanted FHs; control consisted of 31 NFHs unsuitable for transplantation. Myocardial proteins expressions: divalent metal transporter (DMT-1); L-type calcium channel (L-CH); transferrin receptors (TfR-1/TfR-2); ferritins: heavy (FT-H) or light (FT-L) chain, mitochondrial (FT-MT); ferroportin (FPN), regulatory factors and oxidative stress marker: 4-hydroxynonenal (4-HNE). In FH, the expression in almost all proteins responsible for iron transport: DMT-1, TfR-1, L-CH, except TfR-2, and storage: FT-H/-L/-MT were reduced, with no changes in FPN. Moreover, 4-HNE expression (pg/mg; NFH 10.6 ± 8.4 vs. FH 55.7 ± 33.7; p < 0.0001) in FH was increased. HNE-4 significantly correlated with DMT-1 (r = −0.377, p = 0.036), L-CH (r = −0.571, p = 0.001), FT-H (r = −0.379, p = 0.036), also FPN (r = 0.422, p = 0.018). Reducing iron-gathering proteins and elevated oxidative stress in failing hearts is very unfavorable for myocardiocytes. It should be taken into consideration before treatment with drugs or supplements that elevate free oxygen radicals in the heart.