Low-level laser in the treatment of patients with hypothyroidism induced by chronic autoimmune thyroiditis: a randomized, placebo-controlled clinical trial

Lasers Med Sci. 2013 May;28(3):743-53. doi: 10.1007/s10103-012-1129-9. Epub 2012 Jun 21.

Abstract

Chronic autoimmune thyroiditis (CAT) is the most common cause of acquired hypothyroidism, which requires lifelong levothyroxine replacement therapy. Currently, no effective therapy is available for CAT. Thus, the objective of this study was to evaluate the efficacy of low-level laser therapy (LLLT) in patients with CAT-induced hypothyroidism by testing thyroid function, thyroid peroxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb), and ultrasonographic echogenicity. A randomized, placebo-controlled trial with a 9-month follow-up was conducted from 2006 to 2009. Forty-three patients with a history of levothyroxine therapy for CAT-induced hypothyroidism were randomly assigned to receive either 10 sessions of LLLT (830 nm, output power of 50 mW, and fluence of 707 J/cm(2); L group, n=23) or 10 sessions of a placebo treatment (P group, n=20). The levothyroxine was suspended 30 days after the LLLT or placebo procedures. Thyroid function was estimated by the levothyroxine dose required to achieve normal concentrations of T3, T4, free-T4 (fT4), and thyrotropin after 9 months of postlevothyroxine withdrawal. Autoimmunity was assessed by measuring the TPOAb and TgAb levels. A quantitative computerized echogenicity analysis was performed pre- and 30 days postintervention. The results showed a significant difference in the mean levothyroxine dose required to treat the hypothyroidism between the L group (38.59 ± 20.22 μg/day) and the P group (106.88 ± 22.90 μg/day, P<0.001). Lower TPOAb (P=0.043) and greater echogenicity (P<0.001) were also noted in the L group. No TgAb difference was observed. These findings suggest that LLLT was effective at improving thyroid function, promoting reduced TPOAb-mediated autoimmunity and increasing thyroid echogenicity in patients with CAT hypothyroidism.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Autoantibodies / blood
  • Female
  • Hashimoto Disease / complications*
  • Hashimoto Disease / drug therapy
  • Hashimoto Disease / radiotherapy*
  • Humans
  • Hypothyroidism / drug therapy
  • Hypothyroidism / etiology*
  • Hypothyroidism / radiotherapy*
  • Low-Level Light Therapy*
  • Male
  • Middle Aged
  • Thyroid Gland / diagnostic imaging
  • Thyroid Gland / immunology
  • Thyroid Gland / radiation effects
  • Thyroxine / administration & dosage
  • Thyroxine / therapeutic use
  • Ultrasonography

Substances

  • Autoantibodies
  • anti-thyroglobulin
  • thyroid microsomal antibodies
  • Thyroxine