Spona Daniel Camillo, Frodi Diana My, Xing Lucas Yixi, Kongebro Emilie Katrine, Haugan Ketil Jørgen, Graff Claus, Højberg Søren, Krieger Derk, Brandes Axel, Køber Lars, Olesen Morten S, Andersen Andreas, Hædersdal Sofie, Frikke-Schmidt Ruth, Svendsen Jesper Hastrup, Diederichsen Søren Zöga
Department of Cardiology, Copenhagen University Hospital-Rigshospitalet, 2100 Copenhagen, Denmark.
Department of Cardiology, Zealand University Hospital Roskilde, 4000 Roskilde, Denmark.
J Clin Endocrinol Metab. 2025 May 19;110(6):e1975-e1984. doi: 10.1210/clinem/dgae610.
Subclinical thyroid dysfunction is a marker for atrial fibrillation (AF) and stroke risk.
This study explored the effects of AF screening according to thyroid-stimulating hormone (TSH) levels.
An AF screening trial (the LOOP study) was analyzed post hoc according to baseline TSH. The primary outcome was stroke or systemic embolism (SE). Secondary outcomes included major bleeding, all-cause death, and the combination of stroke, SE, and cardiovascular death.
TSH measurements were available in 6003 of 6004 trial participants, 1500 randomized to implantable loop recorder (ILR) screening for AF and anticoagulation upon detection vs 4503 to usual care; mean age was 74.7 ± 4.1 years and 2836 (47%) were women. AF detection was approximately triple for ILR vs usual care across TSH tertiles (adjusted P interaction = 0.44). In the first tertile, screening was associated with decreased risk of the primary outcome (hazard ratio [HR] 0.52, 95% CI 0.30-0.90; P = .02) and stroke, SE, or cardiovascular death (HR 0.54, 95% CI 0.34-0.84; P = .006) compared with usual care, while no effect was observed among participants with higher TSH (adjusted P interaction .03 and .01, respectively). There was no effect on other outcomes. Analyses of continuous TSH or excluding those with abnormal TSH or thyroid medication showed similar results.
AF screening and subsequent treatment was associated with decreased stroke risk among participants with low TSH, though the yield of screening was similar across TSH levels. TSH may be useful as a marker to indicate benefit from AF screening vs overdiagnosis and overtreatment. These findings should be considered exploratory and warrant further study.
亚临床甲状腺功能障碍是心房颤动（AF）和中风风险的一个标志物。
本研究探讨了根据促甲状腺激素（TSH）水平进行AF筛查的效果。
根据基线TSH对一项AF筛查试验（LOOP研究）进行事后分析。主要结局是中风或全身性栓塞（SE）。次要结局包括大出血、全因死亡以及中风、SE和心血管死亡的组合。
6004名试验参与者中有6003人可获得TSH测量值，1500人被随机分配至植入式环路记录仪（ILR）进行AF筛查并在检测到AF后进行抗凝治疗，4503人接受常规治疗；平均年龄为74.7±4.1岁，2836名（47%）为女性。在TSH三分位数中，ILR检测到AF的概率约为常规治疗的三倍（校正P交互作用=0.44）。在第一个三分位数中，与常规治疗相比，筛查与主要结局风险降低相关（风险比[HR]0.52，95%CI 0.30 - 0.90；P = 0.02）以及中风、SE或心血管死亡风险降低相关（HR 0.54，95%CI 0.34 - 0.84；P = 0.006），而在TSH较高的参与者中未观察到效果（校正P交互作用分别为0.03和0.01）。对其他结局无影响。对连续TSH进行分析或排除TSH异常或正在服用甲状腺药物的参与者显示出相似结果。
AF筛查及后续治疗与TSH水平低的参与者中风风险降低相关，尽管TSH各水平的筛查检出率相似。TSH可能作为一个标志物，用于表明AF筛查相对于过度诊断和过度治疗的益处。这些发现应被视为探索性的，需要进一步研究。
