Association Between Vitamin D and Perioperative Hemoglobin Levels in Patients Undergoing Off-pump Coronary Artery Bypass Graft Surgery: Role of Hepcidin

Study Overview
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Brief Summary
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Preoperative anemia is present in more than 50% of patients undergoing cardiac surgery, which is associated with increased risk of transfusion, increased length of stay in the intensive care unit, and increased incidence of renal failure and mortality. To date, clinical research on perioperative anemia has been focused on finding and treating other underlying causes of anemia, lowering the threshold for transfusion, and performing careful transfusion. However, recently, it was known that hepcidin and erythroferrone are related to iron metabolism and absorption, vitamin D has an inverse correlation with the development of anemia, and is related to hepcidin concentration control. Therefore, in this study, the relationship between vitamin D, hepcidin concentration and perioperative hemoglobin level in patients with off-pump coronary artery bypass graft surgery was investigated together.

Official Title
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Association Between Vitamin D and Perioperative Hemoglobin Levels in Patients Undergoing Off-pump Coronary Artery Bypass Graft Surgery: Role of Hepcidin

Conditions
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Coronary Artery Disease

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. Patients over 20 years of age undergoing off-pump coronary artery bypass graft Exclusion Criteria: Emergency operation Minimal invasive coronary artery bypass graft Cooperative operation with other surgery Patients who need a mechanical ventricular assist device Patients with chronic kidney disease (eGFR < 30) Patients who have a end stage renal disease and need a hemodialysis Patients with a low hemoglobin (Hb < 10) before surgery Patients who have a some disease(leukemia, myeloma, aplastic anemia, sickle cell anemia, etc) affecting hematopoiesis Patients with a liver cirrhosis Patients who receive vit. D, iron supplements, erythropoietin within 6 months Patients who cannot understand the informed consent (eg. Foreigner, patients with cognitive dysfunction, etc) Patients who disagree this study

Ages Eligible for Study
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Minimum Age: 20 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Relationship about pre-operative vitamin D level and recovery of hemoglobin | Vitamin D is a fat-soluble vitamin, a regulator acting on bone and calcium metabolism, and is known to affect the pathophysiology of several chronic diseases, and is particularly closely related to heart disease. Vitamin D deficiency was observed in 56% of patients undergoing cardiac surgery, and low vitamin D concentrations increased the risk of postoperative infection and organ failure, atrial fibrillation, and delirium. It is also known that vitamin D is closely related to anemia by regulating the secretion of erythroferrone and changing the concentration of hepcidin. | Up to 1month |