Moulin de Moraes Cristiane M, Mancini Marcio C, de Melo Maria Edna, Figueiredo Daniela Andraus, Villares Sandra Mara F, Rascovski Alessandra, Zilberstein Bruno, Halpern Alfredo
Obesity and Metabolic Syndrome Unit, Endocrinology Service, Hospital das Clínicas, University of São Paulo Medical School, São Paulo, Brazil.
Obes Surg. 2005 Oct;15(9):1287-91. doi: 10.1381/096089205774512537.
There are many studies concerning thyroid function in obesity, and some of them describe higher TSH levels in obese subjects. Few studies evaluated long-term changes in thyroid function caused by weight loss after bariatric surgery. Our aims were to evaluate the prevalence of subclinical hypothyroidism (SH) in a morbidly obese population and to analyze the effect of weight loss induced by Roux-en-Y gastric bypass (RYGBP) on TSH and thyroid hormone (TH) levels.
TSH, free thyroxine (fT4) and total triiodothyronine (T3) levels were analyzed before and 12 months after RYGBP in patients with grade III or grade II obesity with co-morbidities. Subjects taking TH and/or with positive antithyroid antibodies and/or with overt hypothyroidism were excluded.
72 subjects (62F/10M), with mean age 39.6+/-9.8 years and mean BMI 53.0+/-10.4 kg/m2 were studied. The prevalence of SH before RYGBP was 25% (n=18). There was a significant post-surgical decrease in BMI in the whole population, as well as in SH patients. In the SH group and normal TSH group, there was a decrease in TSH and T3, but not in fT4. TSH was not correlated with initial BMI or percent change in BMI. TSH concentrations reached normal values in all SH patients after RYGBP.
Our data confirm that severe obesity is associated with increased TSH. The decrease in TSH was independent of BMI, but occurred in all SH patients. A putative effect of weight reduction on the improvement of SH in all patients may be an additional benefit of bariatric surgery.
有许多关于肥胖症患者甲状腺功能的研究，其中一些研究描述了肥胖受试者促甲状腺激素（TSH）水平较高。很少有研究评估减肥手术后体重减轻引起的甲状腺功能长期变化。我们的目的是评估病态肥胖人群中亚临床甲状腺功能减退症（SH）的患病率，并分析 Roux-en-Y 胃旁路术（RYGBP）引起的体重减轻对 TSH 和甲状腺激素（TH）水平的影响。
对患有 III 级或 II 级肥胖症且伴有合并症的患者在 RYGBP 手术前和术后 12 个月分析 TSH、游离甲状腺素（fT4）和总三碘甲状腺原氨酸（T3）水平。排除正在服用 TH 和/或抗甲状腺抗体阳性和/或患有明显甲状腺功能减退症的受试者。
研究了 72 名受试者（62 名女性/10 名男性），平均年龄 39.6±9.8 岁，平均体重指数（BMI）为 53.0±10.4kg/m²。RYGBP 手术前 SH 的患病率为 25%（n = 18）。整个人群以及 SH 患者术后 BMI 均显著下降。在 SH 组和正常 TSH 组中，TSH 和 T3 下降，但 fT4 未下降。TSH 与初始 BMI 或 BMI 的变化百分比无关。RYGBP 手术后所有 SH 患者的 TSH 浓度均达到正常水平。
我们的数据证实严重肥胖与 TSH 升高有关。TSH 的下降与 BMI 无关，但在所有 SH 患者中均出现。体重减轻对所有患者 SH 改善的假定作用可能是减肥手术的额外益处。
