title: Endogenous subclinical thyroid disorders, physical and cognitive function, depression, and mortality in older individuals.
abstract: OBJECTIVE
  To what extent endogenous subclinical thyroid disorders contribute to impaired physical and cognitive function, depression, and mortality in older individuals remains a matter of debate.
  
  
  METHODS
  A population-based, prospective cohort of the Longitudinal Aging Study Amsterdam.
  
  
  METHODS
  TSH and, if necessary, thyroxine and triiodothyronine levels were measured in individuals aged 65 years or older. Participants were classified according to clinical categories of thyroid function. Participants with overt thyroid disease or use of thyroid medication were excluded, leaving 1219 participants for analyses. Outcome measures were physical and cognitive function, depressive symptoms (cross-sectional), and mortality (longitudinal)
  
  
  RESULTS
  Sixty-four (5.3%) individuals had subclinical hypothyroidism and 34 (2.8%) individuals had subclinical hyperthyroidism. Compared with euthyroidism (n=1121), subclinical hypo-, and hyper-thyroidism were not significantly associated with impairment of physical or cognitive function, or depression. On the contrary, participants with subclinical hypothyroidism did less often report more than one activity limitation (odds ratio 0.44, 95% confidence interval (CI) 0.22-0.86). After a median follow-up of 10.7 years, 601 participants were deceased. Subclinical hypo- and hyper-thyroidism were not associated with increased overall mortality risk (hazard ratio 0.89, 95% CI 0.59-1.35 and 0.69, 95% CI 0.40-1.20 respectively).
  
  
  CONCLUSIONS
  This study does not support disadvantageous effects of subclinical thyroid disorders on physical or cognitive function, depression, or mortality in an older population.
authors.affiliation: Department of Internal Medicine and Endocrinology EMGO Institute for Health and Care Research Department of Psychiatry, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands. rt.dejongh@vumc.nl
authors.forename: Renate T
authors.initials: RT
authors.lastname: de Jongh
authors.forename: Paul
authors.initials: P
authors.lastname: Lips
authors.forename: Natasja M
authors.initials: NM
authors.lastname: van Schoor
authors.forename: Kelly J
authors.initials: KJ
authors.lastname: Rijs
authors.forename: Dorly J H
authors.initials: DJ
authors.lastname: Deeg
authors.forename: Hannie C
authors.initials: HC
authors.lastname: Comijs
authors.forename: Mark H H
authors.initials: MH
authors.lastname: Kramer
authors.forename: Jan P
authors.initials: JP
authors.lastname: Vandenbroucke
authors.forename: Olaf M
authors.initials: OM
authors.lastname: Dekkers
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000401:mortality; D003072:Cognition Disorders / Q000209:etiology* / Q000523:psychology; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000209:etiology* / Q000523:psychology; D005260:Female; D005500:Follow-Up Studies; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D006980:Hyperthyroidism / Q000401:mortality / Q000523:psychology; D007037:Hypothyroidism / Q000401:mortality / Q000523:psychology; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology; D009426:Netherlands / Q000453:epidemiology; D009483:Neuropsychological Tests; D013959:Thyroid Diseases / Q000401:mortality / Q000503:physiopathology* / Q000523:psychology*; D013960:Thyroid Function Tests