Vitamin D Deficiency and Postoperative Hypocalcemia

University of Sao Paulo General Hospital

Status and phase: Unknown; Phase 4

Conditions: Hypocalcemia

Treatments: Drug: Cholecalciferol

Study type: Interventional

Funder types: Other

Identifiers

NCT01632514

USaoPauloGH 8624

Details and patient eligibility

About

Hypocalcemia is a frequent adverse event after thyroidectomy. It is usually related to hypoparathyroidism, but preoperative hypocalcemia, hypomagnesemia or vitamin D deficiency contributes to it. This study aims to determine the frequency of vitamin D deficiency or insufficiency in patients submitted to thyroidectomy, to define the risk attributed to vitamin D deficiency to postoperative hypocalcemia, to identify other factors associated to postoperative calcium disorder, and to evaluate the benefit of preoperative treatment of vitamin D deficiency to prevent postoperative hypocalcemia.

Full description

Subjects to be submitted to total thyroidectomy will be included in the study. The investigators will evaluate serum levels of total calcium, ionic calcium, phosphorus, magnesium, creatinine, albumin, alkaline phosphatase, fasting glucose, thyroid stimulating hormone (TSH), free thyroxin (FT4), intact parathyroid hormone (PTH), 25 hydroxy vitamin D (25OHD), osteocalcin, C-terminal telopeptide (CTX) and procollagen type 1 amino-terminal propeptide (P1NP). Patients will be randomized to 3 groups: (1) 30 subjects with 25OHD < 20 ng/mL that will receive 100,000U of cholecalciferol weekly for 4 weeks before surgery, (2) 30 subjects with 25OHD < 20 ng/mL that will not receive cholecalciferol before surgery and (3) 30 controls with 25OHD >= 20 ng/mL that will not receive cholecalciferol before surgery. Afterwards, the investigators will evaluate immediate postoperative PTH and measure serum levels of total calcium, ionic calcium, magnesium, alkaline phosphatase, osteocalcin, CTX and P1NP in first and second postoperative days for further analysis.

Enrollment: 90 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• patients that will be submitted to total thyroidectomy

Exclusion criteria

• < 18 year-old
• chronic renal failure (creatinine > 1.5 mg/dL)
• fasting glucose > 200 mg/dl
• albumin < 3.5 g/L
• preoperative use of calcium supplements, bisphosphonates, corticosteroids

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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90 participants in 3 patient groups

Vitamin D deficiency treatment

Active Comparator group

Description:

subjects with 25OHD \< 20 ng/mL that will receive 100,000U of cholecalciferol weekly for 4 weeks before surgery

Treatment:

Drug: Cholecalciferol

Vitamin D deficiency observation

No Intervention group

Description:

subjects with 25OHD \< 20 ng/mL that will not receive cholecalciferol before surgery

Vitamin D sufficiency

No Intervention group

Description:

controls with 25OHD \>= 20 ng/mL that will not receive cholecalciferol before surgery