Thyroid Status and Pulmonary Thromboembolic Extent: Is There an Association in Patients with Pulmonary Embolism?

BACKGROUND: Thyroid dysfunction has been associated with thrombotic diseases. However, the association between thyroid status and pulmonary thromboembolic extent remains unclear in patients with pulmonary embolism (PE). Thus, this study investigated the association between thyroid status and pulmonary thromboembolic extent and elucidated the clinical significance of thyroid status assessment in patients with PE. METHODS: We retrospectively analyzed data from 118 patients with PE. Pulmonary thromboembolic extent was assessed with computerized tomography obstruction index. RESULTS: Serum free triiodothyronine (FT3) levels were significantly higher in PE patients with greater pulmonary thromboembolic extent than in those with lesser pulmonary thromboembolic extent (4.33[4.04-4.98] vs 4.17[3.33-4.66] pmol/L, p=0.017), but not for serum free thyroxine (FT4) levels (15.33[13.43-16.94] vs 15.36[13.75-17.82] pmol/L, p=0.908) and serum thyroid stimulating hormone (TSH) levels (1.84[1.01-3.00] vs 1.49[0.74-2.58] uIU/mL, p=0.273). Multivariable linear regression analysis revealed that higher serum FT3 levels were independently associated with greater pulmonary thromboembolic extent in patients with PE (β=0.235, p=0.013). CONCLUSION: Higher serum FT3 levels were associated with greater pulmonary thromboembolic extent in patients with PE. This finding suggests that the possibility of extensive pulmonary thromboembolic extent should be noticed for PE patients with higher serum FT3 levels.