Evaluation of the relationship between idiopathic restless legs syndrome and serum hepcidin levels.

INTRODUCTION: The relationship between restless legs syndrome (RLS) and iron deficiency is a well-known topic. However, the etiology of the disease has not been determined. As the central iron deficiency is the most critical biological abnormality for RLS, we planned a study examining the relationship between RLS and hepcidin, which is the only regulatory hormone of iron metabolism known so far. METHODS: International Restless Legs Syndrome Study Group diagnostic criteria (2014) were taken as a basis. A total of 40 RLS patients and 40 healthy controls were included in the study. To avoid the potential variables that might cause secondary RLS, all the participants were asked to provide hemogram, ferritin, iron, thyroid function tests, and sedimentation analysis. The hepcidin levels were measured with a Human Hepcidin (Hepc 25) ELISA kit (MyBioSource). RESULTS: The statistically significant results of our analysis show that the red blood cell count, the neutrophil count, the percentage of lymphocytes and neutrophils, and, more distinctively, hepcidin levels were higher in RLS patients in comparison with the control group. CONCLUSION: In this study, no differences were found in iron and ferritin values. High levels of hepcidin, the main regulator of iron metabolism, in those with primary RLS support the possibility that hepcidin may play a role in the pathogenesis of RLS. We think that larger studies on this subject can give clearer ideas.

Investigation of the relationship between serum irisin level in the idiopathic restless legs syndrome: Could be a marker independent of physical activity?

INTRODUCTION: Restless legs syndrome (RLS) is a common but underdiagnosed neurological syndrome. It is characterized by the feeling of discomfort and desire to move, especially in the lower extremities, which often occurs at night, and the cure or relief of symptoms with movement. Irisin is a hormonelike polypeptide that was first identified in 2012, weighs 22 kDa, consists of 163 amino acids, and is mainly synthesized in muscle. Its synthesis increases with exercise. Here in this study, we planned to investigate the relationship among serum irisin level, physical activity, lipid profile, and RLS. MATERIAL AND METHODS: A total of 35 patients with idiopathic RLS and 35 volunteers were included in the study. Then, venous blood was taken from the participants in the morning after 12 h of night fasting. RESULTS: The mean value of serum irisin level was 16.9 ± 14.1 ng/mL in the case group and 5.1 ± 5.9 ng/mL in the control group, which was statistically quite significant (p < .001). A significant efficiency (under the curve area 0.886 [0.804-0.967]) of irisin value was observed in the differentiation of patients in the case and control groups. DISCUSSION: Serum irisin level was significantly higher in the case group than in the control group. In conclusion, we suggest that irisin may play a role in the pathophysiology of RLS independently of the intensity and duration of physical activity and anthropometric data, such as body weight, body mass index, and waist/hip ratio.