title: Serum Thyrotropin Concentrations Are Not Associated with the Ankle-Brachial Index: Results from Three Population-Based Studies.
abstract: BACKGROUND
  There is only limited data on the potential association between thyroid dysfunction and peripheral arterial disease (PAD).
  
  
  OBJECTIVE
  The aim of our study was to investigate the potential association of thyroid function, as defined by serum concentrations of the clinically used primary thyroid function marker thyrotropin [i.e. thyroid-stimulating hormone (TSH)] and 3,5-diiodothyronine (3,5-T2), with the ankle-brachial index (ABI) as a marker of PAD.
  
  
  METHODS
  We used data from 5,818 individuals from three cross-sectional population-based studies conducted in Northeast (SHIP-2 and SHIP-TREND) and Central Germany (CARLA). Measurement of serum TSH concentrations was conducted in one central laboratory for all three studies. In a randomly selected subpopulation of 750 individuals of SHIP-TREND, serum 3,5-T2 concentrations were measured with a recently developed immunoassay. ABI was measured either by a hand-held Doppler ultrasound using the Huntleigh Dopplex D900 or palpatorily by the OMRON HEM-705CP device.
  
  
  RESULTS
  Serum TSH concentrations were not significantly associated with ABI values in any of the three studies. Likewise, groups of individuals with a TSH <0.3 mIU/l or with a TSH ≥3.0 mIU/l had no significantly different ABI values in comparison with individuals with a TSH in the reference range. Analyses regarding TSH within the reference range or serum 3,5-T2 concentrations did not reveal consistent significant associations with the ABI. No sex-specific associations were detected.
  
  
  CONCLUSIONS
  The results of our study do not substantiate evidence for an association between thyroid function and PAD, but further studies are needed to investigate the associations of overt forms of thyroid dysfunction with PAD.
authors.affiliation: Institute for Community Medicine, Pulmonary Medicine and Infectious Diseases, University Medicine Greifswald, Germany ; DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany.
authors.forename: Till
authors.initials: T
authors.lastname: Ittermann
authors.affiliation: Institute for Community Medicine, Pulmonary Medicine and Infectious Diseases, University Medicine Greifswald, Germany.
authors.forename: Roberto
authors.initials: R
authors.lastname: Lorbeer
authors.affiliation: Institute of Medical Epidemiology, Biostatistics and Informatics, Halle (Saale), Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Tiller
authors.affiliation: Institut für Experimentelle Endokrinologie, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Ina
authors.initials: I
authors.lastname: Lehmphul
authors.affiliation: Institute of Medical Epidemiology, Biostatistics and Informatics, Halle (Saale), Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Kluttig
authors.affiliation: Department of Internal Medicine B - Cardiology, Intensive Care, Pulmonary Medicine and Infectious Diseases, University Medicine Greifswald, Germany ; DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany.
authors.forename: Stephan B
authors.initials: SB
authors.lastname: Felix
authors.affiliation: Department of Medicine III, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany.
authors.forename: Karl
authors.initials: K
authors.lastname: Werdan
authors.affiliation: German Cancer Research Centre, Division of Cancer Epidemiology, Heidelberg, Germany.
authors.forename: Karin Halina
authors.initials: KH
authors.lastname: Greiser
authors.affiliation: Institut für Experimentelle Endokrinologie, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Josef
authors.initials: J
authors.lastname: Köhrle
authors.affiliation: Institute for Community Medicine, Pulmonary Medicine and Infectious Diseases, University Medicine Greifswald, Germany ; DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany.
authors.forename: Henry
authors.initials: H
authors.lastname: Völzke
authors.affiliation: Department of Internal Medicine B - Cardiology, Intensive Care, Pulmonary Medicine and Infectious Diseases, University Medicine Greifswald, Germany ; DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Dörr
keywords: Ankle-brachial index; Epidemiology; Peripheral arterial disease; Population-based study; Thyroid; Thyrotropin