title: Thermogenic response and leptin levels rise after recovery of the euthyroid state.
abstract: OBJECTIVE
  The aims of the study were to compare: a) the thermogenic responses in subclinical hypothyroidism (SH) and euthyroid state; b) the relationship between thermogenic response and leptin level.
  
  
  METHODS
  Thirty women diagnosed with SH (mean age 39.9+/-4.1 yr; body mass index 23.2+/-2.5 kg/m(2)) were enrolled in the study. Thyroid function tests, leptin, and lipid profiles were measured during SH and after stable euthyroidism was recovered. Thermogenic response was measured by Water Immersion Calorimetry during SH and after the euthyroid state was attained.
  
  
  RESULTS
  The mean level of thermogenic response was found to be 1.45+/-0.43 kcal/kg*h in women with SH. It changed to 1.54+/-0.77 kcal/kg*h (p=0.01) in the euthyroid state; the change was statistically significant. Mean level of leptin was found to be 7.22+/-2.6 ng/ml in SH; and 15.8+/-8.0 ng/ml in the euthyroid state. There was a positive correlation between leptin and free T(3) (r=0.460, p=0.009) levels in SH. There were positive correlations between leptin level and fat mass in SH (r=0.820, p=0.01) and in the euthyroid state (r=0.700, p=0.03).
  
  
  CONCLUSIONS
  No correlations were found between thermogenic response and leptin levels in SH and in the euthyroid state. Thermogenic response and leptin levels rose after the euthyroid state was recovered.
authors.affiliation: Department of Endocrinology and Metabolism, Ege University Medical School, Bornova, Izmir, Turkey. fuldensarac@yahoo.com
authors.forename: F
authors.initials: F
authors.lastname: Saraç
authors.forename: A Gökhan
authors.initials: AG
authors.lastname: Ozgen
authors.forename: G
authors.initials: G
authors.lastname: Celebi
authors.forename: M
authors.initials: M
authors.lastname: Pehlivan
authors.forename: H
authors.initials: H
authors.lastname: Uluer
authors.forename: C
authors.initials: C
authors.lastname: Yilmaz
mesh_terms: D000328:Adult; D015992:Body Mass Index; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood* / Q000503:physiopathology*; D020738:Leptin / Q000097:blood*; D022722:Thermogenesis / Q000502:physiology*
chemical_list: D020738:Leptin