title: Radioiodine therapy in patients with Graves' disease and the effects of prior carbimazole therapy.
abstract: The use of radioiodine as the first line of treatment in Graves' disease is restricted in India because of its limited availability and an unrealistic risk perception associated with it. Additionally, the effectiveness of radioiodine ablation in Graves' disease is influenced by many factors. Prior medical antithyroid therapy is one such important factor.
  
  
  OBJECTIVE
  To analyze the efficacy of low dose radioiodine therapy (5 mCi) in treatment of naive patients of Graves' disease in comparison to that in which it was already primed with an antithyroid drug, carbimazole.
  
  
  METHODS
  A non-randomized, interventional study conducted in the Department of Medicine and Endocrinology of a tertiary care institute in South India.
  
  
  METHODS
  The study had two groups; Group A (36 treatment naive, uncomplicated Graves' disease patients) and B (34 Graves' disease patients on carbimazole prior to radioiodine therapy). Both groups had baseline clinical, biochemical evaluation and were reassessed at 3 and 6 months for evaluating the clinical status for possible documentation of cure.
  
  
  RESULTS
  The cure rate was 61.1% in drug naive group and 58.8% in pretreated group at 6 months following radioiodine (P = 0.845). Higher baseline 999m technicium (99m Tc) uptake, male gender, BMI and higher baseline free thyroxine (fT4) level predicted treatment failure following radioiodine therapy.
  
  
  CONCLUSIONS
  Administration of carbimazole prior to low dose radioiodine therapy does not alter the efficacy of radioiodine. Low fixed dose (5 mCi) of radioactive iodine may be a safe and effective primary therapeutic option in Graves' disease patients pretreated with antithyroid drugs.
authors.affiliation: Department of Medicine, Jawaharlal Institute of Post-graduate Medical Education and Research, Puducherry, India.
authors.forename: Arun
authors.initials: A
authors.lastname: Karyampudi
authors.affiliation: Department of Medicine, Jawaharlal Institute of Post-graduate Medical Education and Research, Puducherry, India.
authors.forename: Abdoul
authors.initials: A
authors.lastname: Hamide
authors.affiliation: Department of Nuclear Medicine, Jawaharlal Institute of Post-graduate Medical Education and Research, Puducherry, India.
authors.forename: Dhanapathi
authors.initials: D
authors.lastname: Halanaik
authors.affiliation: Department of Endocrinology, Jawaharlal Institute of Post-graduate Medical Education and Research, Puducherry, India.
authors.forename: Jaya Prakash
authors.initials: JP
authors.lastname: Sahoo
authors.affiliation: Department of Endocrinology, Jawaharlal Institute of Post-graduate Medical Education and Research, Puducherry, India.
authors.forename: Sadishkumar
authors.initials: S
authors.lastname: Kamalanathan
keywords: Fixed low dose; Graves’ disease; radioiodine ablation; treatment failure; treatment naïve