Internal Medicine Department, Endocrinology division, Alexandria University Student Hospital, Alexandria, Egypt.
Internal Medicine Department, Endocrinology division, Faculty of Medicine, Alexandria University, Alexandria, Egypt.
Endocrine. 2023 Oct;82(1):78-86. doi: 10.1007/s12020-023-03361-3. Epub 2023 Jul 25.
Subclinical hyperthyroidism (SCH) is found to be associated with renal dysfunction. Hyperthyroidism is a well-known cause of secondary systolic hypertension. However, the effect of SCH on the kidney and its vasculature is still unknown.
To assess the presence of renal function changes and renal vasodysfunction in SCH patients and their relation to hypertension.
The study included 321 patients with SCH and 80 healthy matched controls. Laboratory investigations included thyroid function tests, anti-TSH receptor antibody (TRAb), creatinine, estimated glomerular filtration rate (eGFR), serum osmolarity (S. Osmol), urine osmolarity (U. Osmol), Fractional Excretion of Sodium (FeNa), Fractional Excretion of Potassium (FeK), copeptin (CPP), and aldosterone/renin ratio (ARR). Ultrasound for the thyroid gland, echocardiography, total peripheral resistance (TPR), flow-mediated dilatation (FMD), and Renal Arterial distensibility (RAD) was also done.
Serum creatinine was significantly lower while eGFR was significantly higher in SCH patients compared to euthyroid subjects (mean 0.59 ± 0.11 mg/dl Vs mean 0.8 ± 0.1 mg/dl, p = 0.001 and mean 128.28 ± 14.69 ml/min/1.73m2 Vs mean 100.49 ± 14.9 ml/min/1.73m2, p = 0.013, respectively). The TPR and FMD showed a significant decrease in SCH group compared to controls (mean 975.85 ± 159.33 mmHg.min/L Vs mean 1120.24 ± 135.15 mmHg.min/L, p = 0.045 and mean 7.03 ± 4.02% Vs mean 13.48 ± 4.57%, p = 0.003, respectively). RAD was significantly higher in hypertensive SCH patients compared to normotensive SCH patients (mean 17.82 ± 2.46 mmHg Vs mean 11.98 ± 3.21 mmHg, p = 0.001).
SCH patients showed vascular resistance reduction. Alterations in thyroid hormones and blood pressure could be the driving mechanisms for the change in renal functions in patients with SCH.
亚临床甲状腺功能亢进症（SCH）与肾功能障碍有关。甲状腺功能亢进症是继发性收缩期高血压的已知原因。然而，SCH 对肾脏及其血管的影响尚不清楚。
评估 SCH 患者肾功能变化和肾血管舒张功能障碍及其与高血压的关系。
该研究纳入了 321 名 SCH 患者和 80 名健康匹配对照者。实验室检查包括甲状腺功能检测、抗促甲状腺激素受体抗体（TRAb）、肌酐、估算肾小球滤过率（eGFR）、血清渗透压（S. Osmol）、尿渗透压（U. Osmol）、钠排泄分数（FeNa）、钾排泄分数（FeK）、 copeptin（CPP）和醛固酮/肾素比值（ARR）。还进行了甲状腺超声、超声心动图、总外周阻力（TPR）、血流介导的舒张（FMD）和肾动脉可扩张性（RAD）检查。
与甲状腺功能正常者相比，SCH 患者的血清肌酐明显降低，而 eGFR 明显升高（平均 0.59±0.11mg/dl 与平均 0.8±0.1mg/dl，p=0.001；平均 128.28±14.69ml/min/1.73m2 与平均 100.49±14.9ml/min/1.73m2，p=0.013）。与对照组相比，SCH 组的 TPR 和 FMD 明显降低（平均 975.85±159.33mmHg.min/L 与平均 1120.24±135.15mmHg.min/L，p=0.045；平均 7.03±4.02%与平均 13.48±4.57%，p=0.003）。与血压正常的 SCH 患者相比，高血压 SCH 患者的 RAD 明显更高（平均 17.82±2.46mmHg 与平均 11.98±3.21mmHg，p=0.001）。
SCH 患者表现出血管阻力降低。甲状腺激素和血压的变化可能是 SCH 患者肾功能变化的驱动机制。
