title: Impact of lithium on efficacy of radioactive iodine therapy for Graves' disease: a cohort study on cure rate, time to cure, and frequency of increased serum thyroxine after antithyroid drug withdrawal.
abstract: BACKGROUND
  Radioactive iodine (RAI) is a common therapy for hyperthyroidism due to Graves' disease. A small but significant proportion of patients have recurrence of hyperthyroidism after RAI therapy. Lithium might increase RAI effectiveness by increasing RAI retention in the thyroid. However, whether lithium favorably affects the long-term outcome of RAI therapy is still a matter of argument.
  
  
  OBJECTIVE
  The objective of the study was to compare the efficacy of RAI given with or without concomitant lithium treatment.
  
  
  METHODS
  This was a retrospective cohort study.
  
  
  METHODS
  The study was conducted at a tertiary university center.
  
  
  METHODS
  Six hundred fifty-one patients with newly diagnosed Graves' disease participated in the study.
  
  
  METHODS
  Two hundred ninety-eight patients were treated with RAI plus lithium (900 mg/d for 12 d) and 353 with RAI alone.
  
  
  METHODS
  Proportion of cured patients and time to achieve cure of hyperthyroidism during 1 yr of follow-up was measured.
  
  
  RESULTS
  PATIENTS treated with RAI plus lithium had a higher cure rate (91.0%) than those treated with RAI alone (85.0%, P = 0.030). In addition, patients treated with RAI plus lithium were cured more rapidly (median 60 d) than those treated with RAI alone (median 90 d, P = 0.000). Treatment with lithium prevented the serum free T(4) increase after methimazole withdrawal and RAI therapy. Side effects after RAI therapy occurred in a subset of patients and were mild, transient, and without differences in the two groups.
  
  
  CONCLUSIONS
  RAI combined with lithium is safe and more effective than RAI alone in the cure of hyperthyroidism due to Graves' disease.
authors.affiliation: Department of Endocrinology and Metabolism, and Epidemiology and Biostatistics Unit (G.R.), Institute of Clinical Physiology, National Research Council, 56124 Pisa, Italy. fbogazzi@hotmail.com
authors.forename: Fausto
authors.initials: F
authors.lastname: Bogazzi
authors.forename: Clara
authors.initials: C
authors.lastname: Giovannetti
authors.forename: Rezene
authors.initials: R
authors.lastname: Fessehatsion
authors.forename: Maria Laura
authors.initials: ML
authors.lastname: Tanda
authors.forename: Alberto
authors.initials: A
authors.lastname: Campomori
authors.forename: Emanuele
authors.initials: E
authors.lastname: Compri
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Rossi
authors.forename: Claudia
authors.initials: C
authors.lastname: Ceccarelli
authors.forename: Paolo
authors.initials: P
authors.lastname: Vitti
authors.forename: Aldo
authors.initials: A
authors.lastname: Pinchera
authors.forename: Luigi
authors.initials: L
authors.lastname: Bartalena
authors.forename: Enio
authors.initials: E
authors.lastname: Martino
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D013956:Antithyroid Agents / Q000627:therapeutic use; D015331:Cohort Studies; D005260:Female; D006111:Graves Disease / Q000097:blood / Q000188:drug therapy* / Q000453:epidemiology / Q000532:radiotherapy*; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood / Q000188:drug therapy / Q000453:epidemiology* / Q000532:radiotherapy; D015994:Incidence; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008094:Lithium / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012074:Remission Induction; D012189:Retrospective Studies; D013974:Thyroxine / Q000097:blood*; D013997:Time Factors; D016896:Treatment Outcome; D028761:Withholding Treatment; D055815:Young Adult
chemical_list: D013956:Antithyroid Agents; D007457:Iodine Radioisotopes; D008094:Lithium; D013974:Thyroxine