Iron Deficiency Treatment in Patients with Heart Failure

The underlying pathological mechanism of ferroptosis in the development of cardiovascular disease

Cardiovascular diseases (CVDs) have been attracting the attention of academic society for decades. Numerous researchers contributed to figuring out the core mechanisms underlying CVDs. Among those, pathological decompensated cellular loss posed by cell death in different kinds, namely necrosis, apoptosis and necroptosis, was widely regarded to accelerate the pathological development of most heart diseases and deteriorate cardiac function. Recently, apart from programmed cell death revealed previously, ferroptosis, a brand-new cellular death identified by its ferrous-iron-dependent manner, has been demonstrated to govern the occurrence and development of different cardiovascular disorders in many types of research as well. Therefore, clarifying the regulatory function of ferroptosis is conducive to finding out strategies for cardio-protection in different conditions and improving the prognosis of CVDs. Here, molecular mechanisms concerned are summarized systematically and categorized to depict the regulatory network of ferroptosis and point out potential therapeutic targets for diverse cardiovascular disorders.

In-depth review: is hepcidin a marker for the heart and the kidney?

Iron is an essential trace element involved in oxidation-reduction reactions, oxygen transport and storage, and energy metabolism. Iron in excess can be toxic for cells, since iron produces reactive oxygen species and is important for survival of pathogenic microbes. There is a fine-tuning in the regulation of serum iron levels, determined by intestinal absorption, macrophage iron recycling, and mobilization of hepatocyte stores versus iron utilization, primarily by erythroid cells in the bone marrow. Hepcidin is the major regulatory hormone of systemic iron homeostasis and is upregulated during inflammation. Hepcidin metabolism is altered in chronic kidney disease. Ferroportin is an iron export protein and mediates iron release into the circulation from duodenal enterocytes, splenic reticuloendothelial macrophages, and hepatocytes. Systemic iron homeostasis is controlled by the hepcidin-ferroportin axis at the sites of iron entry into the circulation. Hepcidin binds to ferroportin, induces its internalization and intracellular degradation, and thus inhibits iron absorption from enterocytes, and iron release from macrophages and hepatocytes. Recent data suggest that hepcidin, by slowing or preventing the mobilization of iron from macrophages, may promote atherosclerosis and may be associated with increased cardiovascular disease risk. This article reviews the current data regarding the molecular and cellular pathways of systemic and autocrine hepcidin production and seeks the answer to the question whether changes in hepcidin translate into clinical outcomes of all-cause and cardiovascular mortality, and cardiovascular and renal end-points.

Prognostic role of transferrin saturation in heart failure patients

AIMS

In heart failure (HF) iron deficiency (ID) is frequently observed and represents a major mortality risk factor. Purpose of this study was to evaluate the correlation between mortality and ID in a cohort of 661 consecutive patients hospitalized for HF worsening.

METHODS AND RESULTS

Patients were grouped: (i)according to presence(+)/absence(-) of anaemia (A) and ID defined following World Health Organization (WHO) and European Society of Cardiology (ESC)-American College of Cardiology/American Heart Association/HF society of America (ACC/AHA/HFSA) definitions, respectively: Group A-ID- (n = 123), Group A+ID- (n = 80), Group A+ID+ (n = 247), and Group A-ID+ (n = 211); (ii) according to presence of absolute (serum ferritin < 100μg/L) and functional ID [ferritin between 100 and 300μg/L and transferrin saturation (TSAT) < 20%]; and (iii) according to TSAT <20% and ≥20%. Groups were not different for several clinical features but age, gender, kidney function, and chronic obstructive pulmonary disease. Average follow-up was 1.94 year (±420 days). Overall 5 years mortality rate was 29.5%. Only anaemia and functional ID but not ID as defined by guidelines showed an impact on prognosis. Transferrin saturation <20% (n = 360) patients showed worst prognosis compared to TSAT ≥20% (n = 301) patients. In addition, functional ID patients showed worse prognosis compared patients with ferritin <100μg/L and TSAT <20% or ≥20% likely due to more severe chronic inflammatory status [C-reactive protein, 7.4 (interquartile range 2.7-22.6) and 3.2 (1.4-8.7) mg/L, P < 0.0001 respectively].

CONCLUSION

We confirmed that in HF anaemia is associated to a poor prognosis. Moreover, we showed that patients with TSAT <20% had worse prognosis compared to those with TSAT ≥20% but the composite of ferritin between 100 and 300 μg/L and TSAT <20% identifies HF patients with the poorest survival rate.

New drugs: big changes in conservative heart failure therapy?

During the last 20 years, the prognosis for heart failure (HF) with reduced ejection fraction has steadily improved due to advances in drug treatment and the consistent implementation of guideline-recommended evidence-based drug therapy. Nevertheless, the morbidity and mortality rates of patients with HF can still be improved. The prevalence of HF is high and continues to increase steadily. Thus, timely and efficient drug treatment plays a central role in improving the quality of life and prognosis for patients with HF. Current therapeutic concepts combine inhibition of the renin–angiotensin–aldosterone system with blockage of the sympathetic system. New therapeutic approaches such as selective heart rate reduction, attenuation of the degradation of natriuretic peptides by neutral endopeptidase inhibition and treatment of comorbidities (e.g. iron deficiency, diabetes mellitus, hyperkalaemia) have led to a further improvement in the survival, time-out-of hospital and quality of life of affected patients. The goal of this article was to give an overview of the current standard drug therapy for HF and the value of new therapeutic approaches implemented in recent years.

Outcomes of patients with anemia and renal dysfunction in hospitalized heart failure with preserved ejection fraction (from the CN-HF registry)

Background

Although a large number of studies on heart failure with reduced ejection fraction (HFrEF) have found that anemia and renal dysfunction (RD) independently predicted poor outcomes, there are still few reports on patients with heart failure with preserved ejection fraction (HFpEF).

Methods

Clinical data of HFpEF patients registered in the China National Heart Failure Registration Study (CN-HF) were evaluated and the clinical features of patients with or without anemia/RD were compared to explore the impact of anemia and RD on all-cause mortality and all-cause re-hospitalization.

Results

1604 patients with HFpEF were enrolled, the prevalence of anemia was 51.0%. Although anemia was associated with increased risk of all-cause mortality and all-cause re-hospitalization in univariate COX regression (p < 0.05), multivariate COX model confirmed that anemia was not independently associated with all-cause mortality [hazard ratio (HR) 1.14, 95% confidence interval (CI) 0.85–1.52, p = 0.386] and all-cause re-hospitalization (HR 1.13, 95% CI 0.96–1.33, p = 0.152). Similarly, RD was not an independent predictor of all-cause mortality (HR 1.18, 95% CI 0.88–1.57, p = 0.269) and all-cause re-hospitalization (HR 0.94, 95% CI 0.79–1.12, p = 0.488) as assessed in the adjusted COX regression model. The interaction between RD and anemia on end-points events was also not statistically significant. However, anemia was associated with increased all-cause re-hospitalization in patients with New York Heart Association (NYHA) class III-IV.

Conclusions

In patients with HFpEF from CN-HF registry, anemia was common, but was not an independent predictor of all-cause mortality and all-cause re-hospitalization, except for the all-cause re-hospitalization in patients with NYHA class III-IV.

Clinical Trial Registration: http://www.clinicaltrials.gov/ct2/home; ID: NCT02079428.

Randomized supplementation of 4000 IU vitamin D3 daily vs placebo on the prevalence of anemia in advanced heart failure: the EVITA trial

Background

Low 25-hydroxyvitamin D (25OHD) levels (< 75 nmol/l) are inversely associated with anemia prevalence. Since anemia and low 25OHD levels are common in patients with heart failure (HF), we aimed to investigate whether vitamin D supplementation can reduce anemia prevalence in advanced HF.

Methods

EVITA (Effect of Vitamin D on Mortality in Heart Failure) is a randomized, placebo-controlled clinical trial in patients with initial 25OHD levels < 75 nmol/l. Participants received either 4000 IU vitamin D₃ daily or a matching placebo for 36 months. A total of 172 patients (vitamin D group: n = 85; placebo group: n = 87) were investigated in this pre-specified secondary data analysis. Hemoglobin (Hb) and other hematological parameters were measured at baseline and study termination. Assessment of between-group differences in anemia prevalence and Hb concentrations was performed at study termination, while adjusting for baseline differences.

Results

In the vitamin D and placebo group, baseline proportions of patients with anemia (Hb < 12.0 g/dL in females and < 13.0 g/dL in males) were 17.2% and 10.6%, respectively (P = 0.19). At study termination, the proportion of patients with anemia in the vitamin D and placebo groups was 32.2% and 31.8%, respectively (P > 0.99). There was no between-group difference in change in the Hb concentrations (− 0.04 g/dL [95%CI:-0.53 to 0.45 g/dL]; P = 0.87). Results regarding anemia risk and Hb concentrations were similar in the subgroup of patients with chronic kidney disease (vitamin D group: n = 26; placebo group: n = 23). Moreover, results did not differ substantially when data analysis was restricted to patients with deficient baseline 25OHD levels.

Conclusions

A daily vitamin D supplement of 4000 IU did not reduce anemia prevalence in patients with advanced HF. Data challenge the clinical relevance of vitamin D supplementation to increase Hb levels.

Trial registration

The study was registered at EudraCT (No. 2010–020793-42) and clinicaltrials.gov (NCT01326650).

Electronic supplementary material

The online version of this article (doi:10.1186/s12937-017-0270-5) contains supplementary material, which is available to authorized users.