title: Gluten-free diet may alleviate depressive and behavioural symptoms in adolescents with coeliac disease: a prospective follow-up case-series study.
abstract: BACKGROUND
  Coeliac disease in adolescents has been associated with an increased prevalence of depressive and disruptive behavioural disorders, particularly in the phase before diet treatment. We studied the possible effects of a gluten-free diet on psychiatric symptoms, on hormonal status (prolactin, thyroidal function) and on large neutral amino acid serum concentrations in adolescents with coeliac disease commencing a gluten-free diet.
  
  
  METHODS
  Nine adolescents with celiac disease, aged 12 to 16 years, were assessed using the semi-structured K-SADS-Present and Lifetime Diagnostic interview and several symptom scales. Seven of them were followed at 1 to 2, 3, and 6 months on a gluten-free diet.
  
  
  RESULTS
  Adolescent coeliac disease patients with depression had significantly lower pre-diet tryptophan/ competing amino-acid (CAA) ratios and free tryptophan concentrations, and significantly higher biopsy morning prolactin levels compared to those without depression. A significant decrease in psychiatric symptoms was found at 3 months on a gluten-free diet compared to patients' baseline condition, coinciding with significantly decreased coeliac disease activity and prolactin levels and with a significant increase in serum concentrations of CAAs.
  
  
  CONCLUSIONS
  Although our results of the amino acid analysis and prolactin levels in adolescents are only preliminary, they give support to previous findings on patients with coeliac disease, suggesting that serotonergic dysfunction due to impaired availability of tryptophan may play a role in vulnerability to depressive and behavioural disorders also among adolescents with untreated coeliac disease.
authors.affiliation: Hospital for Children and Adolescents, Helsinki University Central Hospital, Helsinki, Finland. paivi.pynnonen@pp.fimnet.fi
authors.forename: Päivi A
authors.initials: PA
authors.lastname: Pynnönen
authors.forename: Erkki T
authors.initials: ET
authors.lastname: Isometsä
authors.forename: Matti A
authors.initials: MA
authors.lastname: Verkasalo
authors.forename: Seppo A
authors.initials: SA
authors.lastname: Kähkönen
authors.forename: Ilkka
authors.initials: I
authors.lastname: Sipilä
authors.forename: Erkki
authors.initials: E
authors.lastname: Savilahti
authors.forename: Veikko A
authors.initials: VA
authors.lastname: Aalberg
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000596:Amino Acids / Q000097:blood; D016022:Case-Control Studies; D002446:Celiac Disease / Q000097:blood / Q000178:diet therapy* / Q000453:epidemiology; D002648:Child; D015331:Cohort Studies; D015897:Comorbidity; D003866:Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy*; D018753:Diet, Protein-Restricted / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D005983:Glutens / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy*; D011388:Prolactin / Q000097:blood; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D013960:Thyroid Function Tests; D016896:Treatment Outcome; D014364:Tryptophan / Q000097:blood
chemical_list: D000596:Amino Acids; D005983:Glutens; D014364:Tryptophan; D011388:Prolactin