Endocrinology Division, Clinical Medicine Department, Faculty of Medical Sciences, University of Campinas, Campinas, Brazil.
Endocr J. 2013;60(7):877-84. doi: 10.1507/endocrj.ej13-0030. Epub 2013 Apr 5.
Previous reports highlight the role of systemic inflammation in the genesis of non-thyroidal illness syndrome and type 2 diabetes mellitus (T2DM). Our objective was to assess whether body mass index and the low-grade systemic inflammation would be associated with changes in thyroid hormone metabolism in patients with type 2 diabetes. This was a cross-sectional study of 104 subjects; 52 patients with type 2 diabetes and 52 in a control group, paired by age, gender and body mass index. We measured total (T) and free (F) thyroxine (T4) and triiodothyronine (T3), reverse T3 (rT3), the ratios FT3/rT3, FT3/FT4 and FT4/rT3, clinical parameters (age, gender, diabetes duration and complications, body mass index, waist circumference, hypertension, HbA1c), and high sensitivity C-reactive protein. Patients with DM presented lower levels of TT4 (p=0.006), TT3 (p<0.001) and FT3 (p<0.001) and higher of FT4 (p<0.001), waist circumference (p=0.047) and C-reactive protein (p<0.001). Body mass index was inversely correlated with FT4 (p=0.036) and TT3 (p=0.008). C-reactive protein was positively correlated with rT3 (p=0.001) and inversely with FT4/rT3 (p<0.001) and FT3/rT3 (p=0.014). Body mass index was an independent predictor for FT4 (B=-0.011, p=0.029) and TT3 levels (B=-1.118, p=0.003). Inflammation predicted the FT4/rT3 ratio (B=-0.190, p<0.001). C-reactive protein (B=0.235, p<0.001) and body mass index (B=-0.008, p=0.047) were independent predictors for rT3. In conclusion, type 2 diabetes was associated with a low T3 state. Body mass index and the low-grade systemic inflammation are related to the non-thyroidal illness syndrome in these patients, possibly by altering the activity of peripheral deiodinases.
先前的报告强调了全身炎症在非甲状腺疾病综合征和 2 型糖尿病（T2DM）发病机制中的作用。我们的目的是评估体重指数和低度全身炎症是否与 2 型糖尿病患者甲状腺激素代谢的变化有关。这是一项横断面研究，共纳入 104 例患者；52 例 2 型糖尿病患者和 52 例对照组，两组按年龄、性别和体重指数配对。我们测量了总（T）和游离（F）甲状腺素（T4）和三碘甲状腺原氨酸（T3）、反式三碘甲状腺原氨酸（rT3）、FT3/rT3、FT3/FT4 和 FT4/rT3 比值、临床参数（年龄、性别、糖尿病病程和并发症、体重指数、腰围、高血压、HbA1c）和高敏 C 反应蛋白。DM 患者 TT4（p=0.006）、TT3（p<0.001）和 FT3（p<0.001）水平降低，FT4（p<0.001）、腰围（p=0.047）和 C 反应蛋白（p<0.001）水平升高。体重指数与 FT4（p=0.036）和 TT3（p=0.008）呈负相关。C 反应蛋白与 rT3（p=0.001）呈正相关，与 FT4/rT3（p<0.001）和 FT3/rT3（p=0.014）呈负相关。体重指数是 FT4（B=-0.011，p=0.029）和 TT3 水平（B=-1.118，p=0.003）的独立预测因子。炎症预测了 FT4/rT3 比值（B=-0.190，p<0.001）。C 反应蛋白（B=0.235，p<0.001）和体重指数（B=-0.008，p=0.047）是 rT3 的独立预测因子。结论：2 型糖尿病与低 T3 状态有关。体重指数和低度全身炎症与这些患者的非甲状腺疾病综合征有关，可能通过改变外周脱碘酶的活性。
