Heald Adrian H, Premawardhana Lakdasa D, Taylor Peter N, Baker Adam, Chaudhury Nadia, Fryer Anthony A, Okosieme Onyebuchi E, Dayan Colin M, Stedman Mike
The School of Medicine and Manchester Academic Health Sciences Centre, University of Manchester, Manchester, UK.
Department of Endocrinology and Diabetes, Salford Royal Hospital, Salford, UK.
Clin Endocrinol (Oxf). 2025 Apr;102(4):490-495. doi: 10.1111/cen.15185. Epub 2024 Dec 19.
There continues to be much discussion around optimisation of thyroid hormone status in hypothyroid individuals. We here looked the way that free T4(FT4) and thyroid-stimulating hormone (TSH) related to each other in a large laboratory sample of people who underwent a thyroid function test (TFT), split between those on levothyroxine replacement (monitoring test) and those who underwent a test to check for thyroid hormone imbalance (diagnostic test; not on levothyroxine).
TFT test (FT4/TSH) results were extracted from the Salford Royal Hospital Laboratory Information Management System during 2009-2012. This was a single site study. Requests includes a tick box for 'on levothyroxine' (yes or no). To minimise comorbidity effects, only samples taken in General Practices were used. For untreated patients only those who had single tests results were used; for treated patients, the median value across all their results was used. Cluster analysis considered an ellipse with centre on median values for log (TSH) and FT4 and the vertex based on 5% and 95% percentile values of both. The percentage of patients falling outside the ellipse boundary was considered for both treated and untreated populations.
The total data set included 290,000 tests on 130,000 individuals. After filtering, FT4/TSH results were used from 12,006 (F 9231/M 2775; age < 60 5850/age ≥ 60 6567) treated patients with 43,846 test results. These were compared to the single results for 43,394 untreated patients (F 24,386/M19,008; age < 60 32,537/age ≥ 60 10,857). Cluster analysis showed for untreated patients, median values for TSH and FT4 were 1.8 mU/L and 15.5 pmol/L, respectively, with 24% of patient results falling outside the untreated 5%/95% percentiles. For treated patients, the median TSH was 2.3 mU/L (+30% vs. untreated) and FT4 was 18.9 pmol/L (+22% vs. untreated), with 22% of treated patients falling outside the treated 5%/95% percentiles. When considered against the untreated limits, 68% of treated results fell outside (split male 63%, female 70% and age < 60 67%, Age ≥ 60 64%).
The current treatment regimens of either low or high dose levothyroxine are not delivering the expected laboratory TFT profiles, with significant numbers of treated patients being well outside the expected values: both TSH and FT4 being significantly higher. This effect appears to be more prevalent in women than men.
关于甲状腺功能减退患者甲状腺激素状态的优化，一直存在诸多讨论。我们在此研究了在接受甲状腺功能测试（TFT）的大量实验室样本中，游离甲状腺素（FT4）和促甲状腺激素（TSH）之间的相互关系，这些样本分为接受左甲状腺素替代治疗的患者（监测测试）和接受甲状腺激素失衡检查的患者（诊断测试；未接受左甲状腺素治疗）。
2009年至2012年期间，从索尔福德皇家医院实验室信息管理系统中提取TFT测试（FT4/TSH）结果。这是一项单中心研究。申请中包括一个“是否接受左甲状腺素治疗”的勾选框（是或否）。为尽量减少合并症的影响，仅使用在全科医疗中采集的样本。对于未治疗的患者，仅使用有单次测试结果的样本；对于接受治疗的患者，使用其所有结果的中位数。聚类分析考虑以log（TSH）和FT4的中位数为中心、顶点基于两者5%和95%百分位数的椭圆。分别考虑治疗组和未治疗组中落在椭圆边界之外的患者百分比。
数据集总共包括对130,000名个体的290,000次测试。经过筛选后，使用了12,006名接受治疗患者（女性9231名/男性2775名；年龄＜60岁5850名/年龄≥60岁6567名）的43,846次FT4/TSH测试结果。将这些结果与43,394名未治疗患者（女性24,386名/男性19,008名；年龄＜60岁32,537名/年龄≥60岁10,857名）的单次测试结果进行比较。聚类分析显示，对于未治疗患者，TSH和FT4的中位数分别为1.8 mU/L和15.5 pmol/L，24%的患者结果落在未治疗组的5%/95%百分位数之外。对于接受治疗的患者，TSH中位数为2.3 mU/L（比未治疗组高30%），FT4为18.9 pmol/L（比未治疗组高22%），22%的接受治疗患者结果落在治疗组的5%/95%百分位数之外。与未治疗组的范围相比，68%的治疗结果超出范围（男性占63%，女性占70%；年龄＜60岁占67%，年龄≥60岁占64%）。
目前低剂量或高剂量左甲状腺素的治疗方案未能实现预期的实验室TFT指标，大量接受治疗的患者结果远超出预期值：TSH和FT4均显著更高。这种影响在女性中似乎比男性更普遍。
