Serum thyroid hormone autoantibodies in type 1 diabetes mellitus

J Clin Endocrinol Metab. 2015 May;100(5):1870-8. doi: 10.1210/jc.2014-3950. Epub 2015 Feb 24.

Abstract

Context: Autoimmune thyroid diseases (AITDs) can be associated with type 1 diabetes (DM1). The prevalence of serum antibodies against thyroid hormones (THAb) in subjects with autoimmune diseases other than DM1 is increasing. No data are available for DM1.

Objective: The objectives were evaluate the rate of associated AITD; the rate of positiveness for serum THAb; the panel of THAb based on thyroid hormone interaction and on Ig class; and the association of AITD alone, THAb alone, or AITD plus THAb with diabetes-related complications.

Design: This was an observational, prospective study with 6-year (2005-2011) follow-up.

Setting: The setting was an outpatient diabetes clinic.

Patients: Fifty-two consecutive subjects (53.8% males; mean age, 37.4 ± 7.4 y; diabetes duration, 19.9 ± 8.2 y) with DM1. All participants completed the study.

Main outcome measures: Main outcome measures were AITD rate; THAb positivity according to hormone interaction and Ig class; association of AITD and THAb with diabetes-related complications.

Results: AITD rate increased from baseline (34.6%) to follow-up (38.5%). Subjects with DM1 had a high prevalence of THAb (92.3%). The presence of AITD at baseline was associated with subsequent development of macroangiopathy (0 vs 33% at baseline and follow-up, respectively; P = .029). Some THAb patterns, the majority having T3 binding in common, were associated with the progression and development of diabetes-related complications.

Conclusions: THAb synthesis in DM1 might be driven by increased glycosylation of thyroglobulin. Anti T3-THAb may cause a relative "tissue hypothyroidism" by sequestering thyroid hormone, this at least partially contributing to worsening diabetes-related vascular complications. In a clinical setting THAb positivity could identify subjects more likely to develop diabetes complications.

MeSH terms

  • Adult
  • Autoantibodies / blood*
  • Autoantigens / immunology*
  • Diabetes Mellitus, Type 1 / blood
  • Diabetes Mellitus, Type 1 / immunology*
  • Female
  • Humans
  • Iodide Peroxidase / immunology*
  • Iron-Binding Proteins / immunology*
  • Male
  • Middle Aged
  • Prospective Studies
  • Thyroglobulin / immunology*

Substances

  • Autoantibodies
  • Autoantigens
  • Iron-Binding Proteins
  • Thyroglobulin
  • TPO protein, human
  • Iodide Peroxidase