title: Prevalence of hyperthyrotropinemia in obese children before and after weight loss.
abstract: BACKGROUND
  Obesity is a worldwide epidemic. In recent years, increasing attention has been focused on thyroid function in obesity.
  
  
  OBJECTIVE
  To establish the prevalence of elevated thyroid-stimulating hormone (TSH) levels in obese children and adolescents, and identify the relationship between TSH levels and other metabolic and hormonal variables before and after weight reduction.
  
  
  METHODS
  We evaluated 150 obese subjects (aged 3-17 years) for anthropometric, biochemical, metabolic and hormonal variables. Measurements were taken at baseline and, in a subgroup of children with hyperthyrotropinemia, after a 6-month intervention program based on exercise, behavior therapy, and nutrition education.
  
  
  RESULTS
  At baseline, 23 participants (15.3 %) had hyperthyrotropinemia, and 21 of these patients completed the weight reduction intervention. Among these 21 patients, 14 had substantial weight loss and a significant decrease in TSH and free T3 levels.
  
  
  CONCLUSIONS
  We conclude that TSH and T3 levels are significantly increased in childhood obesity; in most cases, however, these increases cannot be elucidated by thyroid autoimmunity or iodine deficiency. If thyroid disorders are excluded beforehand, an elevated TSH with normal thyroid hormone levels in obese children seems rather a consequence than a cause of obesity since weight loss leads to a normalization of elevated TSH levels. In this context, thyroid hormone alterations in obesity suggest an adaptation process.
authors.affiliation: Clinics of Pediatric Endocrinology, Dr. Sami Ulus Women Health, Children's Education and Research Hospital, Ankara, Turkey, veyselbas@yahoo.com.
authors.forename: Veysel Nijat
authors.initials: VN
authors.lastname: Baş
authors.forename: Zehra
authors.initials: Z
authors.lastname: Aycan
authors.forename: Sebahat Yılmaz
authors.initials: SY
authors.lastname: Ağladıoğlu
authors.forename: Havva Nur Peltek
authors.initials: HN
authors.lastname: Kendirci
mesh_terms: D000293:Adolescent; D001835:Body Weight; D002648:Child; D002675:Child, Preschool; D015444:Exercise; D005260:Female; D015438:Health Behavior; D006801:Humans; D008297:Male; D009765:Obesity / Q000097:blood* / Q000628:therapy; D013972:Thyrotropin / Q000097:blood*; D015431:Weight Loss
chemical_list: D013972:Thyrotropin