研究背景：
　　葛瑞夫氏症是最常見造成甲狀腺機能亢進症的原因，臨床上以體重下降及代謝異常等為表現，治療之後往往伴隨體重增加；然而，經藥物治療後體重變化之預測因子與對代謝症候群盛行率之影響仍舊尚未明朗。這次的研究目的即著重於甲狀腺機能亢進症經藥物治療後體重與代謝指標的改變。

研究方法：
　　本次研究為一前瞻性的世代觀察研究。在成大醫院內分泌科門診中徵募新診斷之甲狀腺機能亢進症患者，於藥物治療期間定期收集病患的身體測量學指標（包含身高、體重、腰臀圍等）、生化資料（包含血糖、血脂肪、肝腎功能等）及甲狀腺功能，透過多變項線性迴歸分析體重變化之預測因子、卡方檢定比較藥物治療前後的代謝症候群盛行率的改變，並以麥內班檢定確認代謝症候群之各項因素是否改變。

研究結果：
　　本次研究總共納入94位新診斷之葛瑞夫氏症病人（包含男性31人與女性63人），經藥物治療後三個月、六個月、九個月及十二個月，其恢復至甲狀腺機能正常的比率分別為86.2%、85.1%、88.3%、85.1%；在男性身上，體重於一個月、三個月、六個月、九個月及十二個月後，分別為69.3 ± 13.0公斤、72.0 ± 12.6公斤、73.0 ± 12.4公斤、74.2 ± 13.2公斤、74.7 ± 13.3公斤，而在女性身上，體重於一個月、三個月、六個月、九個月及十二個月後，分別為54.0 ± 7.6公斤、55.7 ± 7.5公斤、56.0 ± 7.7公斤、56.6 ± 8.3公斤、56.7 ± 8.3公斤。經多變項線性迴歸分析發現，男性患者可藉由一個月的體重變化預測一年的體重變化（β 1.501，95% CI 0.733~2.270，p <0.001），女性患者可藉由前三個月的體重變化預測一年的體重變化(β 1.041，95% CI 0.750~1.332，P <0.001)；另一方面，代謝症候群盛行率於藥物治療十二個月後明顯上升（由7.8%增至23.3%，p = 0.001），主要由於中央肥胖增加（由42.6%增至59.6%，p = 0.001）及高密度膽固醇下降（由22.0%增至45.1%，p = 0.001）所影響。

結論：
　　本研究發現男性甲狀腺機能亢進症患者可藉治療一個月後的體重變化預測一年後的體重變化，女性甲狀腺機能亢進症患者則可藉治療三個月後的體重變化預測一年後的體重變化；藥物治療後代謝症候群的盛行率上升主因來自於中央肥胖增加及高密度膽固醇下降的改變。因此，我們建議在甲狀腺機能亢進症治療期間，應注意體重管理的重要性。

Introduction
Graves’ disease is the most common cause of thyrotoxicosis presented with significant weight loss and metabolic abnormalities. Treatment of Graves’ disease frequently results in weight gain. However, the predictors of post-treatment body weight gain, and the impact of treatment on metabolic syndrome development remain unknown. The aim of this study was to evaluate the changes of body weight and metabolic abnormalities after thionamide treatment of Graves’ disease.

Methods
This is a prospective observational study. Patients with newly diagnosed hyperthyroidism were recruited from outpatient clinic. Anthropometric measurements, biochemistry data, and thyroid function tests were collected during the treatment periods. Multivariate linear regressions were conducted to explore the predictors of body weight change. Chi-square tests were conducted to compare the prevalence of metabolic syndrome before and after treatment, and the McNemar tests were used to determine if there were differences of metabolic syndrome components.

Results
A total of 94 patients (male/female: 31/63) with newly diagnosed Graves’ disease was included. After thionamide treatment, 86.2%, 85.1%, 88.3%, and 85.1% of subjects achieved euthyroidism (normal free T4) at 3m, 6m, 9m, and 12m, respectively. The BW were 69.3 ± 13.0 Kg, 72.0 ± 12.6 Kg, 73.0 ± 12.4 Kg, 74.2 ± 13.2 Kg, and 74.7 ± 13.3 Kg at 1m, 3m, 6m, 9m and 12m, respectively, in male subjects, and 54.0 ± 7.6 Kg, 55.7 ± 7.5 Kg, 56.0 ± 7.7 Kg, 56.6 ± 8.3 Kg, and 56.7 ± 8.3 Kg in females. The multivariate linear regressions showed that weight gain during the first month predicts one-year weight gain in men (β 1.501, 95% CI 0.733~2.270 , P <0.001), and weight gain during the first three months predicts one-year weight gain in women (β 1.041, 95% CI 0.750~1.332, p <0.001). In addition, the prevalence of metabolic syndrome increased significantly 12m after treatment (from 7.8% to 23.3%. p = 0.001), which was contributed by the increased percentage of central obesity (from 42.6% to 59.6%. p = 0.001) and low-HDL (from 22.0% to 45.1%. p = 0.001) among the five components of metabolic syndrome.

Conclusion
We found that weight gain during the first month predicts one-year weight gain in men, and weight gain during the first three months predicts one-year weight gain in women. Furthermore, the prevalence of metabolic syndrome increased significantly after treatment, which was contributed by the increased percentage of central obesity and low-HDL among the five components of metabolic syndrome. Our results suggest the importance of weight management in patients with Graves’ disease receiving antithyroid treatment.

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