Graves’ disease: is hyperthyroidism still present 6 months after radioactive iodine treatment really a failure?
Nuclear Medicine Communications, cilt.46, sa.11, ss.1037-1042, 2025 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 46 Sayı: 11
- Basım Tarihi: 2025
- Doi Numarası: 10.1097/mnm.0000000000002033
- Dergi Adı: Nuclear Medicine Communications
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, EMBASE, MEDLINE
- Sayfa Sayıları: ss.1037-1042
- Anahtar Kelimeler: Graves' disease, hypothyroidism, radioactive iodine treatment, thyrotoxicosis
- Sağlık Bilimleri Üniversitesi Adresli: Evet
Özet
Aim – This study aimed to evaluate the accuracy of the 6-month evaluation to accept treatment failure after a single dose of radioactive iodine (RAI) for Graves’ disease and to decide whether to repeat the dose. Methods – This study retrospectively analyzed 104 patients who received a single dose of RAI between 2003 and 2022, had regular follow-up for at least 2 years, and did not have extrathyroidal symptoms. The study group was divided into two groups: patients who developed hypothyroidism within the first 6 months and patients who developed hypothyroidism after 6 months, and statistically analyzed. Results – The mean administered dose of RAI was 10.6 ± 4.4 mCi, and the average duration of hypothyroidism was 5.5 ± 5.4 months. In patients with late-onset hypothyroidism (>6 months), the 2-h iodine uptake values were significantly higher, and post-RAI thyroid-stimulating hormone levels were significantly lower. While 58.5% of patients with early-onset hypothyroidism (<6 months) required antithyroid drug (ATD) therapy after RAI, all patients who developed hypothyroidism after 6 months received supportive ATD treatment. The 24-h iodine uptake values were significantly higher in the hypothyroid group compared with the euthyroid group. During follow-up, 26.9% of patients were hypothyroid at 0–3 months, 62.5% at 3–6 months, and 77.9% at 12 months. While 20.2% of patients remained hyperthyroid at 6 months, this rate declined to 3.8% at 12 months. Conclusion – This study suggests that the 6th month following RAI treatment in patients with Graves’ disease may not be sufficient to assess treatment response, as hypothyroidism tends to develop cumulatively over time. Iodine uptake values at 2 and 24 h may serve as useful indicators for predicting the development of early or late hypothyroidism, while also helping to guide the maintenance of a euthyroid state.