title: Increased prevalence of hyperthyroidism as an early and transient side-effect of implementing iodine prophylaxis.
abstract: OBJECTIVE
  To assess the prevalence of hyperthyroidism just after implementation of iodine prophylaxis among adults from an area with iodine deficiency.
  
  
  METHODS
  A total of 1648 adults (age 16 years and older) were sampled from an area of southern Poland during two nationwide epidemiological surveys. Of these, 1424 adults with negative medical history for thyroid disorders qualified for final analysis. The authors compared thyroid dysfunction in participants prior to (1989-1990) and after implementation of iodine prophylaxis (1997-1999).
  
  
  METHODS
  The southern part of Poland.
  
  
  RESULTS
  We found an increase in the serum concentration of anti-thyroid microsomal antibodies from 4.9% in the years 1989-1990 to 12.1% after introduction of iodised household salt (P < 0.0001). The prevalence of hyperthyroidism (defined as thyroid-stimulating hormone < 0.4 microU ml- 1) significantly increased in the equivalent period from 4.8 to 6.5% (P = 0.009).
  
  
  CONCLUSIONS
  We concluded that a sudden rise in iodine intake after implementation of iodine prophylaxis among adults from the area with iodine deficiency may lead to an increase in thyroid autoimmunity and prevalence of hyperthyroidism. Those possible early side-effects appear to be only temporary and are acceptable when compared with the evident benefits of adequate iodine intake.
authors: Department of Endocrinology, Jagiellonian University Faculty of Medicine, Kopernika 17, 31-501 Krakow, Poland. filgol@cm-uj.krakow.pl
authors: Filip
authors: F
authors: Gołkowski
authors: Monika
authors: M
authors: Buziak-Bereza
authors: Małgorzata
authors: M
authors: Trofimiuk
authors: Agata
authors: A
authors: Bałdys-Waligórska
authors: Zbigniew
authors: Z
authors: Szybiński
authors: Bohdan
authors: B
authors: Huszno
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood / Q000139:chemically induced* / Q000453:epidemiology; D007037:Hypothyroidism / Q000097:blood / Q000517:prevention & control*; D007455:Iodine / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood / Q000172:deficiency; D008297:Male; D008875:Middle Aged; D011044:Poland; D015995:Prevalence; D017673:Sodium Chloride, Dietary; D013972:Thyrotropin / Q000097:blood; D014131:Trace Elements / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood; D016896:Treatment Outcome
chemical_list: D017673:Sodium Chloride, Dietary; D014131:Trace Elements; C034024:iodized salt; D013972:Thyrotropin; D007455:Iodine