Red cell distribution width - a new marker for exacerbation of heart failure in patients with hypothyroidism following radioiodine therapy

Changes in serum hepcidin according to thyrometabolic status in patients with Graves' disease

INTRODUCTION

Hepcidin is an acute-phase protein and a key regulator of iron homeostasis. Anaemia frequently occurs in patients with thyroid dysfunction, and hepcidin may be a potential link.

OBJECTIVES

Prospective assessment of hepcidin serum concentration and other parameters related to Fe homeostasis in hyperthyroid patients in the course of GD at diagnosis and during remission.

PATIENTS AND METHODS

Out of 70 patients recruited, 42 (32 women, 10 men), aged 42.5±15.1 years, met the inclusion criteria. Clinical and biochemical assessment, including hepcidin measurement by ELISA, was performed at baseline (T0) and after restoration of euthyroidism (T1).

RESULTS

Hepcidin concentration at T0 in the 24 patients who completed the study was significantly higher than the value during euthyroidism (28.7 (8.1-39.4) ng/mL vs. 7.9 (4.3-12.9) ng/mL, p<0.001). Hepcidin level was most significantly correlated with ferritin (rho = 0.723) in women at T0. In both men (377 (171-411) vs. 165 (84-237) ng/mL, p=0.001) and women (84 (23-104) vs. 35 (16-64) ng/mL, p=0.001), a significant decrease in ferritin level was demonstrated following therapy. A significant (p<0.001) increase in mean corpuscular volume (MCV) (83.5 (82.5-87.1) vs. 89.5 (88.8-90.0) fL) and mean concentration of haemoglobin (MCH) (29.0 (28.0-29.4) vs. 30.4 (29.5-31.1) pg) was observed.

CONCLUSIONS

Hepcidin and ferritin decrease significantly during the transition from a hyperthyroid state to euthyroidism in patients with GD. The observed changes occur in parallel to iron homeostasis fluctuations. During the transition from the hyperthyroid state to euthyroidism, the improvement of haematological status is reflected mainly by the increase in MCV and MCH.

The hepcidin concentration decreases in hypothyroid patients with Hashimoto's thyroiditis following restoration of euthyroidism

The purpose of the study was to measure the hepcidin concentration and evaluate Fe homeostasis indices in a prospective study on patients with newly diagnosed hypothyroidism in the course of Hashimoto’s thyroiditis (HT) and following successful therapy. The prospective observational study consisted of 34 patients. The clinical evaluation and laboratory tests were performed at diagnosis (T0) and after restoration of euthyreosis 12 weeks later (T1). The median level of hepcidin was significantly lower (p = 0.002) after recovery (7.7 [6.2–13.0] ng/mL) than that before treatment (17.4 [7.6–20.4] ng/mL), while creatinine (p = 0.011) and GFR (p < 0.001) significantly improved after euthyroidism was achieved. A positive correlation was observed between hepcidin and fT3 (p = 0.033, r = 0.465) at T0. In the females, the level of hepcidin positively correlated with ferritin concentration before (p < 0.001, r = 0.928) and after treatment (p < 0.001, r = 0.835). A statistically significant difference was observed in RDW-CV (red blood cell distribution width - coefficient of variation) between the hypothyroid and euthyroid states. In conclusion, a decrease in hepcidin concentration during the transition from the hypothyroid state to euthyroidism in patients with HT is associated with the observed dynamics in iron homeostasis, mainly reflected by improvement in RDW-CV and significant correlations between ferritin and hepcidin as well as between hepcidin and fT3.

Hepcidin and Iron Homeostasis in Patients with Subacute Thyroiditis and Healthy Subjects

Purpose

Hepcidin is an acute-phase protein involved also in regulation of iron homeostasis. The aim of the study was to prospectively assess for the first time the hepcidin_EL concentration in patients with subacute thyroiditis (SAT), to identify biochemical determinants of hepcidin_EL concentration and evaluate the potential role of hepcidin in SAT diagnosis and monitoring.

Methods

Out of 40 patients with SAT initially recruited, restrictive inclusion criteria fulfilled 21 subjects aged 45 ± 10 years and 21 healthy control subjects (CS). Hepcidin_EL concentration, thyroid status, and iron homeostasis were evaluated at SAT diagnosis and following therapy and compared with CS.

Results

The median hepcidin_EL concentration at SAT diagnosis is higher than that in CS (48.8 (15.9-74.5) ng/mL vs. 18.2 (10.2-23.3) ng/mL, p = 0.009) and is significantly lower after treatment (4.0 (1.2-10.0) ng/mL, p = 0.007) compared with CS. The ROC analysis for hepcidin_EL at SAT diagnosis revealed that area under the curve (AUC) is 0.735 (p = 0.009), and the cut-off for hepcidin_EL concentration is 48.8 ng/mL (sensitivity 0.52 and specificity 0.95). Hepcidin_EL in SAT patients correlated with CRP (r = 0.614, p = 0.003), ferritin (r = 0.815, p < 0.001), and aTPO (r = -0.491, p = 0.024). On multiple regression, the correlation between hepcidin_EL and ferritin was confirmed (p < 0.001).

Conclusions

SAT is accompanied by a significant increase in hepcidin, which reflects an acute-phase inflammatory process. Parameters of iron homeostasis improved significantly while inflammatory indices got lower following recovery. The potential role of hepcidin as a predictive factor of the risk of SAT relapse needs to be assessed in studies on larger groups of SAT patients.