Clinical Trial Details
— Status: Not yet recruiting
Administrative data
NCT number |
NCT05871957 |
Other study ID # |
YXLL-KY-2021(041) |
Secondary ID |
|
Status |
Not yet recruiting |
Phase |
|
First received |
|
Last updated |
|
Start date |
June 1, 2023 |
Est. completion date |
September 30, 2023 |
Study information
Verified date |
May 2023 |
Source |
Qianfoshan Hospital |
Contact |
Lin Liao, Doctor |
Phone |
18354117713 |
Email |
liaolin[@]sdu.edu.cn |
Is FDA regulated |
No |
Health authority |
|
Study type |
Observational
|
Clinical Trial Summary
The purpose of this study is to explore the relationship between vitamin D and Hashimoto's
thyroiditis and to explore whether vitamin D can play an adjuvant role in the treatment of
Hashimoto's thyroiditis. Epidemiological surveys show that vitamin D deficiency rates are as
high as 50%-90% in HT patients. Dietary supplementation with vitamin D has been evaluated as
a way to protect the thyroid gland from autoimmune damage, but the results of randomized
clinical trials are unclear.
Description:
Hashimoto's thyroiditis (HT), also known as chronic lymphocytic or autoimmune thyroiditis
(AITD), is a type of chronic autoimmune thyroid disease that is associated with varying
degrees of hypothyroidism, thyroid autoantibody production, and lymphocytic infiltration. In
China, the incidence rate showed a rising trend year by year. For the majority of HT
hypothyroidism patients, synthetic levothyroxine (LT4) (first crystallized by Kendall in
1915, commercialized in the 1930s, and mass-produced in the 1960s) remains the only effective
drug for HT patients. The treatment works for most patients, but is still controversial.
Dietary vitamin D supplementation has been evaluated as a way to protect the thyroid from
autoimmune damage, but results from randomized clinical trials have been inconclusive.
Clinical studies have shown that vitamin D3 supplementation has a unique advantage in
reducing TPO antibody titers. In 2014, AACE (American Association of Clinical
Endocrinologists) guidelines indicated that vitamin D can be used as a complementary
treatment for Hashimoto's thyroiditis. The prevalence of vitamin D deficiency in HT patients
is as high as 50%-90%. Studies have shown that VD is widely used in vivo. VD can be used as
an immune factor to participate in the process of immune regulation. Cells of the immune
system (B cells, T cells and antigen presenting cells) can synthesize active metabolites of
vitamin D due to the expression of 1α-hydroxylase (CYP27B1), which shows immunomodulatory
properties. In addition, studies have shown that Vitamin D receptor (VDR) is found not only
in bone, kidneys, and intestine, but also in the immune system (T and B cells, macrophages,
and monocytes), reproductive system, endocrine system, muscle, brain, skin, and liver. The
expression of the vitamin D receptor in these cells suggests a local role for vitamin D in
immune responses. Existing genetic studies have found that most VDR can be restricted by
CYP1α and vitamin D binding proteins, showing the relationship between VDR, DBP and CYP1α
gene polymorphisms and thyroid autoimmune system, which affect T and B lymphocytes, dendritic
cells and macrophages, as well as enzymes with CYP1α and VDR. Therefore, Vitamin D is thought
to be an immune modulator.
Clinical studies have confirmed that vitamin D deficiency is more common in patients with
autoimmune thyroid disease (AITD), both in children and the elderly, and in both low and high
latitudes. Combining vitamin D with anti-thyroid drugs or thyroid hormones can help treat
AITD by suppressing autoimmune responses and lowering serum levels of thyroid autoantibodies.
However, studies have shown that vitamin D deficiency is not associated with AITD, especially
early AITD. However, a study based on Asian Indian communities found only a weak inverse
association between serum 25-hydroxyvitamin D values and TPO antibody titers. A 2015
meta-analysis demonstrated that vitamin D deficiency is prevalent in AITD subjects and that
these subjects have low serum 25-hydroxyvitamin D levels, suggesting that lower serum
25-hydroxyvitamin D is associated with AITD disease.
There is a complex relationship between HT and serum 25-hydroxyvitamin D. It is not clear
whether the decreased serum 25-hydroxyvitamin D level is one of the causes of HT
hypothyroidism or a consequence of HT.