Department of Emergency Medicine, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan.
Center for Aging and Health, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan.
Thromb Haemost. 2020 Mar;120(3):505-514. doi: 10.1055/s-0039-3402761. Epub 2020 Feb 6.
Previous studies have shown that hypothyroidism may have an impact on blood coagulation. However, how hypothyroidism and thyroxine replacement therapy (TRT) affect the risk of venous thromboembolism (VTE) remains controversial. This study aimed to examine the associations of hypothyroidism and TRT with VTE risks.
This nationwide population-based cohort study was conducted using Taiwan's National Health Insurance Research Database. We enrolled 10,818 hypothyroid patients (the exposed cohort) and 21,636 non-hypothyroid subjects (the unexposed cohort) between 2001 and 2014 after 1:2 exact matching according to age, sex, and index year. Hypothyroid patients were further divided into two groups depending on whether they received TRT or not. Adjusted hazard ratios (aHRs) for VTE were calculated using Fine and Gray competing risk models.
The mean follow-up period was 7.5 years. Hypothyroidism was significantly associated with a higher risk of VTE (aHR = 1.83 [95% confidence interval [CI]: 1.44-2.33, < 0.001]). Among hypothyroid patients, the TRT subgroup had a non-significant trend of lower VTE risk than the non-TRT subgroup (aHR = 0.73 [95% CI: 0.52-1.01, = 0.058]). The analysis for individual events revealed a significant association between TRT use and a lower risk of pulmonary embolism among hypothyroid patients (aHR = 0.34 [95% CI: 0.13-0.88, = 0.026]).
The data suggest that hypothyroidism was significantly associated with an increased risk of VTE. Among hypothyroid patients, a non-significant trend of lower VTE risk in patients treated with TRT was observed. Further prospective studies or clinical trials are necessary to confirm causality.
既往研究表明甲状腺功能减退症可能对凝血产生影响。然而，甲状腺功能减退症和甲状腺素替代治疗（TRT）如何影响静脉血栓栓塞症（VTE）的风险仍存在争议。本研究旨在探讨甲状腺功能减退症和 TRT 与 VTE 风险的关系。
本项全国性基于人群的队列研究使用了台湾全民健康保险研究数据库。我们在 2001 年至 2014 年间招募了 10818 例甲状腺功能减退症患者（暴露队列）和 21636 例非甲状腺功能减退症患者（未暴露队列），并按照年龄、性别和索引年份进行了 1:2 精确匹配。甲状腺功能减退症患者根据是否接受 TRT 进一步分为两组。使用 Fine 和 Gray 竞争风险模型计算 VTE 的调整后危险比（aHR）。
平均随访时间为 7.5 年。甲状腺功能减退症与 VTE 风险升高显著相关（aHR=1.83[95%置信区间（CI）：1.44-2.33，<0.001]）。在甲状腺功能减退症患者中，TRT 亚组的 VTE 风险较非 TRT 亚组呈下降趋势，但无统计学意义（aHR=0.73[95%CI：0.52-1.01，=0.058]）。对单个事件的分析显示，TRT 的使用与甲状腺功能减退症患者中肺栓塞风险降低显著相关（aHR=0.34[95%CI：0.13-0.88，=0.026]）。
数据表明甲状腺功能减退症与 VTE 风险增加显著相关。在甲状腺功能减退症患者中，接受 TRT 治疗的患者 VTE 风险呈下降趋势，但无统计学意义。需要进一步的前瞻性研究或临床试验来确认因果关系。
