title: Effects of L-thyroxine on gastric motility and ghrelin in subclinical hypothyroidism: a prospective study.
abstract: BACKGROUND
  Overt hypothyroidism affects the gastrointestinal system. Limited data are available regarding gastric motility in subclinical hypothyroidism (SCH).
  
  
  OBJECTIVE
  The aim of this study was to assess gastric motility-related gastric symptoms and levels of ghrelin in patients with SCH compared with those in healthy control subjects and to evaluate the potential effects of l-thyroxine replacement therapy.
  
  
  METHODS
  Twenty premenopausal women with SCH and 20 age- and body mass index-matched healthy control women were enrolled in the study. The gastroparesis cardinal severity index questionnaire was used to reveal gastrointestinal motility changes, and electrogastrographic activities were measured. Fasting and postprandial ghrelin levels at 30, 60, and 120 minutes were determined during a mixed meal test. All tests were repeated after 6 months when patients were in the euthyroid state.
  
  
  RESULTS
  The gastroparesis cardinal severity index score, fasting tachygastria ratio, and postprandial/fasting bradygastria ratio in electrogastrography were higher in patients with SCH compared with control subjects (P = .03, P = .04, and P = .04, respectively). All 3 parameters significantly improved after l-thyroxine replacement therapy (P < .001, P = .005, and P =.02 respectively) reaching levels similar to those of control subjects. Baseline and area under the curve for ghrelin during mixed meal tests did not show a difference between patients with SCH and control subjects and before and after l-thyroxine replacement in SCH.
  
  
  CONCLUSIONS
  Gastric dysmotility and the resultant upper gastrointestinal symptoms can be observed in SCH, and symptomatology related to dysmotility and parameters appear to be improved with thyroid hormone replacement. Our results also suggest that ghrelin levels in response to a meal are similar between women with SCH and healthy women and that normalization of thyroid function by l-thyroxine does not modulate these levels.
authors.affiliation: Hacettepe University Faculty of Medicine, Department of Internal Medicine, Division of Endocrinology and Metabolism, 06100 Ankara, Turkey. yildizbo@yahoo.com.
authors.forename: Asena Gökçay
authors.initials: AG
authors.lastname: Canpolat
authors.forename: Taylan
authors.initials: T
authors.lastname: Kav
authors.forename: Bülent
authors.initials: B
authors.lastname: Sivri
authors.forename: Bülent Okan
authors.initials: BO
authors.lastname: Yildiz
mesh_terms: D000328:Adult; D004415:Dyspepsia / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D004435:Eating / Q000502:physiology; D004594:Electrophysiology / Q000379:methods; D005260:Female; D005746:Gastric Emptying / Q000187:drug effects*; D054439:Ghrelin / Q000097:blood*; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000150:complications / Q000188:drug therapy*; D008875:Middle Aged; D017697:Premenopause; D011446:Prospective Studies; D012720:Severity of Illness Index; D013974:Thyroxine / Q000008:administration & dosage*; D016896:Treatment Outcome
chemical_list: D054439:Ghrelin; D013974:Thyroxine