title: Subclinical hypothyroidism, weight change, and body composition in the elderly: the Cardiovascular Health Study.
abstract: BACKGROUND
  Subclinical hypothyroidism is common in the elderly, yet its relationship with weight and body composition is unclear.
  
  
  OBJECTIVE
  We examined the relationship between subclinical hypothyroidism and weight change and body composition in older adults.
  
  
  METHODS
  A total of 427 subclinically hypothyroid and 2864 euthyroid U.S. individuals ≥65 years old enrolled in the Cardiovascular Health Study and not taking thyroid preparations were included. Analyses of 6-year weight change were performed, compared by thyroid status. A cross-sectional analysis of thyroid status and body composition was performed in a subset of 1276 participants who had dual-energy x-ray absorptiometry scans. Models were risk factor-adjusted and stratified by sex.
  
  
  RESULTS
  Overall, participants lost weight during follow-up (-0.38 kg/y in men, -0.37 kg/y in women). Subclinical hypothyroidism, when assessed at a single time point or persisting over 2 years, was not associated with a difference in weight change compared with euthyroidism. Subclinical hypothyroidism was also not associated with differences in lean mass, fat mass, or percent fat compared with euthyroidism. A TSH level 1 mU/L higher within the euthyroid or subclinical hypothyroid range was associated with a 0.51-kg higher baseline weight in women only (P < .001) but not with weight change in either sex. A 1 ng/dL higher free T4 level was associated with lower baseline weight and 0.32 kg/y greater weight loss in women only (P = .003). Baseline weight and weight change did not differ by T3 levels.
  
  
  CONCLUSIONS
  Our data do not support a clinically significant impact of subclinical hypothyroidism on weight status in the elderly.
authors.affiliation: Division of Endocrinology, Diabetes, and Metabolism (M.C.G., A.R.C.), Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104; Department of Biostatistics (A.M.A.), University of Washington, Seattle, Washington 98155; Division of Endocrinology, Gerontology, and Metabolism (J.S.L.), Stanford University School of Medicine and Veterans Administration Palo Alto Health Care System, Palo Alto, California 94305; and Departments of Pathology and Biochemistry (R.P.T.), University of Vermont, Burlington, Vermont 05405.
authors.forename: Margaret C
authors.initials: MC
authors.lastname: Garin
authors.forename: Alice M
authors.initials: AM
authors.lastname: Arnold
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Lee
authors.forename: Russell P
authors.initials: RP
authors.lastname: Tracy
authors.forename: Anne R
authors.initials: AR
authors.lastname: Cappola
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D058070:Asymptomatic Diseases; D001823:Body Composition / Q000502:physiology*; D015992:Body Mass Index; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D013961:Thyroid Gland / Q000502:physiology; D015431:Weight Loss / Q000502:physiology*