title: Mild thyroid hormone excess is associated with a decreased physical function in elderly men.
abstract: BACKGROUND
  In the adult, subclinical hyperthyroidism (Shyper) may alter skeletal muscle mass and strength. However, whether these effects are present in elderly subjects is not known. We explored the relationship between mild hyperthyroidism and physical function in a population-based sample of older persons.
  
  
  METHODS
  In a cross-sectional analysis, calf muscle cross-sectional area (CMA), handgrip strength, nerve conduction velocity (NCV), and Short Physical Performance Battery (SPPB) scores were compared between 364 euthyroid (Eut) and 28 Shyper men as well as between 502 Eut and 39 Shyper women. In a longitudinal analysis, we evaluated the relationship between baseline plasma TSH, FT3 and FT4 and the 3-year change in SPPB score in 304 men and 409 women who were euthyroid at enrolment.
  
  
  RESULTS
  At the cross-sectional analysis, Shyper men, but not women, had a significantly (p = 0.02) lower SPPB score than Eut controls, although with comparable CMA, grip strength and NCV, and were more likely to have poor physical performance (odds ratio = 2.97, p < 0.05). Longitudinal analysis showed that in Eut men higher baseline FT4 was significantly (p = 0.02) predictive of a lower SPPB score at the 3-year follow-up.
  
  
  CONCLUSIONS
  Even a modest thyroid hormone excess is associated with a reduced physical function in elderly men.
authors.affiliation: Department of Internal Medicine and Biomedical Sciences, Section of Geriatrics-Endocrine Unit, University of Parma, Parma, Italy. ceresini@unipr.it
authors.forename: Graziano
authors.initials: G
authors.lastname: Ceresini
authors.forename: Gian Paolo
authors.initials: GP
authors.lastname: Ceda
authors.forename: Fulvio
authors.initials: F
authors.lastname: Lauretani
authors.forename: Marcello
authors.initials: M
authors.lastname: Maggio
authors.forename: Stefania
authors.initials: S
authors.lastname: Bandinelli
authors.forename: Jack M
authors.initials: JM
authors.lastname: Guralnik
authors.forename: Anne R
authors.initials: AR
authors.lastname: Cappola
authors.forename: Elisa
authors.initials: E
authors.lastname: Usberti
authors.forename: Simonetta
authors.initials: S
authors.lastname: Morganti
authors.forename: Giorgio
authors.initials: G
authors.lastname: Valenti
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D058070:Asymptomatic Diseases / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005080:Exercise Test; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood / Q000503:physiopathology*; D008137:Longitudinal Studies; D008297:Male; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000503:physiopathology; D009431:Neural Conduction / Q000502:physiology; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine