Prevention of Postoperative Hypocalcemia of Oral Vitamin D Supplementation Before Total Thyroidectomy

Study Overview
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Brief Summary
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The hypocalcemia after total thyroidectomy is one of common surgical complications. It may be asymptomatic, but patients can complain of dysfunction around the mouth or extremities, stiffness or convulsion in severe cases. The incidence of transient hypocalcemia was 6.9-46%, and permanent hypocalcemia was reported to be 0.4-33%. It has been reported that the incidence of hypocalcemia after thyroidectomy is high when the difference in blood levels of parathyroid hormone and vitamin D is large before and after surgery. Therefore, it is a very important task to study the effect of using vitamin D3 (cholecalciferol), which has a better effect on the human body, on the prevention of hypocalcemia after total thyroidectomy with a long follow-up period after surgery. The department of surgery in Seoul National University Hospital intends to analyze the preventive effect D-mac 30,000 IU on postoperative hypocalcemia and safety of 'D-mac 30,000 IU through a prospective randomized clinical trial. The incidence of postoperative hypocalcemia of the group taking orally taking vitamin D3 (cholecalciferol) before surgery will be compared with that of the group not taking vitamin D3 before surgery. Patients who are enrolled in this RCT are allocated to the case group and the control group. Patients in the case group are taking 30,000 IU of vitamin D3 (cholecalciferol) orally, and patients in the control group are not taking any drugs. Primary endpoint of this study is to evaluate the incidence of hypocalcemia. And secondary endpoints are to evaluate the recovery duration from postoperative hypocalcemia and the risk factors for postoperative hypocalcemia.

Official Title
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Study for Effectiveness in Prevention of Postoperative Hypocalcemia of Preoperative Oral Supplementation of Vitamin D (D-mac 30,000 IU) in Patients Undergoing Total Thyroidectomy

Conditions
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Total Thyroidectomy, Hypocalcemia, Vitamin D Deficiency

Intervention / Treatment
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* Drug: Cholecalciferol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged 19 to 70 years old Patients undergoing total thyroidectomy due to thyroid disease Patients who consented to the study and obtained consent for the study Exclusion Criteria: Patients with confirmed hypocalcemia or hypercalcemia before surgery Patients receiving calcium or vitamin D treatment before surgery, patients with excessive vitamin D Patients with a previous history of parathyroid disease or a history of cervical irradiation Patients with confirmed parathyroid comorbidity Patients with diseases or conditions that cause hypercalcemia or hypercalciuria (myeloma, bone metastases, or other malignant bone diseases) Patients with confirmed renal dysfunction (glomerular filtration rate <60mL/min/1.73m2) before surgery or with a history of chronic renal failure Renal stone disease patient, kidney stone disease patient Patients with bowel disease that may affect serum vitamin D levels (celiac disease, small intestine resorption disease, small bowel resection history) Patients taking drugs that may affect serum calcium or vitamin D levels (anticonvulsants, bisphosphonates, cisplatin, aminoglycosides, diuretics, proton pump inhibitors, glucocorticoid benzodiazepine derivatives, etc.) Uncontrolled hypertension, diabetes, and clotting disorders Cardiovascular disease (angina pectoris, heart failure, myocardial infarction, coronary artery disease, history of arrhythmia treatment, stroke, transient ischemic attack), and taking medications for arrhythmia Drug Abuse and Alcohol Abuse Patients who participated in other drug clinical trials within 30 days Patients with a history of allergies to drugs For women, pregnant and lactating patients Patients judged unsuitable by the person in charge of the clinical trial Patients with genetic problems such as galactose intolerance, lactose deficiency, or glucose-galactose malabsorption disorder

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Since the concentration of D-mac 30,000 IU in the body reaches the maximum in the body around 1 to 3 weeks after administration, the drug is taken once 15 days before the surgery so that the vitamin D3 concentration is maximized at the time of surgery. In the case of the control group, there is no drug to be taken.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: case group<br>One dose of 30,000 IU of D-mac is taken once 15 days prior to surgery. | Drug: Cholecalciferol<br>* Since the concentration of D-mac 30,000 IU in the body reaches the maximum in the body around 1 to 3 weeks after administration, the drug is taken once 15 days before the surgery so that the vitamin D3 concentration is maximized at the time of surgery. In the case of the control group, there is no drug to be taken.<br>|
| No Intervention: control group<br>There is no 30,000 IU of D-mac to be taken. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative hypocalcemia | The incidence of hypocalcemia at postoperative 1 day | postoperative 1 day | 
| Postoperative hypocalcemia | The incidence of hypocalcemia at postoperative 2 weeks | postoperative 2 weeks | 
| Postoperative hypocalcemia | The incidence of hypocalcemia at postoperative 3 months | postoperative 3 months | 
| Postoperative hypocalcemia | The incidence of hypocalcemia at postoperative 6 months | postoperative 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The occurrence of hypocalcemia sign | The results of survey about the occurrence of hypocalcemia sign | 1 day, 2 weeks, 3 months, 6 months after surgery | 
| Duration of recovery period from postoperative hypocalcemia | Duration for recovery from hypocalcemia after thyroidectomy | 1 day, 2 weeks, 3 months, 6 months after surgery | 
| Risk factors for developing postoperative hypocalcemia | Risk factors associated with postoperative hypocalcemia | 1 day, 2 weeks, 3 months, 6 months after surgery |