Low-Level Laser Therapy in Chronic Autoimmune Thyroiditis

Study Overview
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Brief Summary
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The purpose of this study is to evaluate whether low-level Laser therapy is effective in ameliorating the thyroid function of patients with hypothyroidism caused by chronic autoimmune thyroiditis.

Detailed Description
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Chronic autoimmune thyroiditis (CAT) is the most common cause of hypothyroidism in iodine-replete areas. An autoimmune dysfunction causes humoral and cellular responses that lead progressively to thyroiditis. There is no effective therapy available that can change the natural history of CAT, which presents a high incidence of hypothyroidism and requires continuous treatment with levothyroxine (LT4). Laser light can be valuable since the local and systemic actions of low-level laser therapy (LLLT) have been shown to be effective in treating autoimmune diseases, such as rheumatoid arthritis and Sjogren's syndrome. There is also evidence suggesting that LLLT can facilitate regeneration of various tissues and, in animal thyroids, can lead to improvement in microcirculation and increases in serum triiodothyronine (T3) and thyroxine (T4) levels. Since the LLLT is a non-invasive, cost-effective and painless procedure, the objective of this randomized clinical trial was to evaluate the effectiveness of LLLT in patients with hypothyroidism caused by chronic autoimmune thyroiditis, based on patients' thyroid function, their concentration of thyroid autoantibodies, and the parameters of their ultrasonography study.

Official Title
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Low-Level Laser Therapy in Chronic Autoimmune Thyroiditis: Randomized, Placebo Controlled Clinical Trial

Conditions
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Autoimmune Thyroiditis

Intervention / Treatment
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* Device: Low-level Laser therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients previously diagnosed with hypothyroidism induced by chronic autoimmune thyroiditis (CAT). The presence of hypothyroidism, laboratory measurements and ultrasonography criteria were applied to diagnose CAT. Significantly elevated concentrations of thyroid peroxidase (TPOAb) and/or thyroglobulin (TgAb) autoantibodies Ultrasonography results consistent with CAT Patients undergoing LT4 treatment Normal (or almost normal) levels of triiodothyronine (T3), thyroxine (T4), free T4 and thyrotropin (TSH) Exclusion Criteria: Use of immunosuppressants, immunostimulants, or other drugs that could interfere with the production, metabolism and transport of thyroid hormones CAT with normal thyroid function CAT with subclinical hypothyroidism Thyroid nodules Hypothyroidism stemming from post-partum thyroiditis (up to 18 months after gestation) History of Graves' disease Thyrotropin receptor antibody (TRAb) detectable Prior treatment with radioiodine Tracheal stenosis Pregnancy History of ionizing irradiation and/or neoplasia in the cervical area Previous surgical intervention in the thyroid Thyroid hypoplasia Ectopic thyroid Serious illness (cancer, ischemic coronary artery disease, stroke, kidney or liver failure, etc.)

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Sham Laser<br>Ten applications of placebo were performed (twice a week) with the same method and Laser equipment, which has a placebo function available with a red ordinary light indistinguishable of the Laser light. | Device: Low-level Laser therapy<br>* A continuous wave (CW) diode laser device (830nm, infrared) with a beam area of 0.2827cm2 and using the punctual method, continuous emission mode, output power of de 50mW and fluence of 70J/cm2 (40 seconds at the point of application).<br>* Other names: Low power Laser therapy;|
| Active Comparator: Active Laser<br>Ten applications of low-level Laser therapy (twice a week) were performed with a continuous wave diode laser device (830nm, beam area of 0.2827cm2), using the punctual method, continuous emission mode, output power of de 50 mW and fluence of 70J/cm2. | Device: Low-level Laser therapy<br>* A continuous wave (CW) diode laser device (830nm, infrared) with a beam area of 0.2827cm2 and using the punctual method, continuous emission mode, output power of de 50mW and fluence of 70J/cm2 (40 seconds at the point of application).<br>* Other names: Low power Laser therapy;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The main outcome measure was to gauge the effectiveness of applying LLLT in patients with hypothyroidism caused by CAT evaluated by a significant reduction of the levothyroxine (LT4) mean dose (µ/day) 9 months post-LT4 withdrawal. | All patients enrolled in the study were undergoing LT4 treatment. They received 10 applications of LLLT or placebo. Thirty days after intervention, LT4 was discontinued in all patients and, if required, reintroduced. T3, T4, free T4 and TSH levels (all laboratory personnel was blinded), were assessed pre-LLLT and then 1, 2, 3, 6 and 9 months post-LT4 withdrawal. The LT4 mean dose pre-LLLT and 9 months post-LT4 withdrawal was compared both in face of normal levels of T3, T4, free T4 and TSH to evaluate LLLT effectiveness. | LT4 dose, concentrations of T3, T4, free T4 and TSH were evaluated and compared before intervention and 9 months post-LT4 withdrawal. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluate the LLLT efficacy in reducing thyroid autoantibodies concentrations. | Thyroid peroxidase (TPOAb) and thyroglobulin (TgAb) autoantibodies were both determined prior to LLLT and in the 1st, 2nd, 3rd, 6th and 9th months after LT4 withdrawal. All laboratory personnel was blinded to treatment assignment throughout the study. | Thyroid autoantibodies were determined and compared pre-intervention and 9 months post-LT4 withdrawal. | 
| Evaluate the LLLT efficacy by quantitative and qualitative ultrasonography parameters. | B-mode sonography (volume, texture and echogenicity using computerized histogram) as well as power Doppler (vascularization) and pulsed Doppler (maximal systolic peak velocity and resistance index for the thyroid arteries) were performed and compared pre- and 30 days post-intervention by only one experienced and blind investigator, during the use of the same doses of LT4. | The ultrasonography parameters observed pre-LLLT were compared with those observed 30 days post-LLLT. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Autoimmune Thyroiditis, Laser, Therapy, Thyroid, Ultrasound