title: Linear growth and intellectual outcome in children with long-term idiopathic subclinical hypothyroidism.
abstract: OBJECTIVE
  The treatment of children with subclinical hypothyroidism (SH) is controversial for TSH values between 4.5 and 10 mU/l. The aim of this cross-sectional, controlled study was to evaluate growth and intellectual outcome in children with persistent SH who have never been treated with levothyroxine.
  
  
  METHODS
  Clinical and auxological parameters, thyroid function, and intellectual outcome were evaluated in 36 children with persistent SH at the age of 9.7±0.6 (range 4-18.0) years. Children had been followed longitudinally for 3.3±0.3 (range 2.0-9.3) years, from first diagnosis of SH until enrollment in the study. Thirty-six age- and sex-matched children were enrolled in the study as controls.
  
  
  RESULTS
  At study entry, height (-0.8±0.2 SDS), bone age/chronological age (BA/CA ratio 0.92±0.6), and body mass index (BMI -0.1±0.2 SDS) in SH children were normal. Despite long-term duration of SH, none of these parameters showed a worsening with respect to height (-0.7±0.2 SDS), BA/CA (0.97±0.03), and BMI (-0.1±0.2) at the time of first SH detection. None of the children showed overt signs or symptoms of hypothyroidism during the follow-up. Verbal (99.1±2.2), performance (100.4±1.9), and full-scale (99.7±1.9) intelligence quotient (IQ) scores in SH children were normal and comparable to those of controls. No relationship was detected between IQ scores and the degree or duration of SH.
  
  
  CONCLUSIONS
  Persistent SH in children is not associated with alterations in growth, bone maturation, BMI, and cognitive function or other complaints that could be ascribed to SH even after several years without therapeutic intervention.
authors.affiliation: Department of Pediatrics, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Cerbone
authors.forename: Carmela
authors.initials: C
authors.lastname: Bravaccio
authors.forename: Donatella
authors.initials: D
authors.lastname: Capalbo
authors.forename: Miriam
authors.initials: M
authors.lastname: Polizzi
authors.forename: Malgorazata
authors.initials: M
authors.lastname: Wasniewska
authors.forename: Daniela
authors.initials: D
authors.lastname: Cioffi
authors.forename: Nicola
authors.initials: N
authors.lastname: Improda
authors.forename: Mariella
authors.initials: M
authors.lastname: Valenzise
authors.forename: Dario
authors.initials: D
authors.lastname: Bruzzese
authors.forename: Filippo
authors.initials: F
authors.lastname: De Luca
authors.forename: Mariacarolina
authors.initials: M
authors.lastname: Salerno
mesh_terms: D000293:Adolescent; D001827:Body Height / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000503:physiopathology*; D007360:Intelligence / Q000502:physiology*; D008297:Male