Pulmonary hypertension and Hashimoto's thyroiditis: does a relationship exist?

Several studies examined the possibility that idiopathic pulmonary hypertension is related to thyroid autoimmune diseases. The aim of our study was to highlight the possible correlations between the pulmonary hypertension and Hashimoto's thyroiditis (HT). A total of 93 patients were enrolled, 70 suffering from HT in euthyroidism state and 23 controls. All underwent anthropometric [weight (Kg); height (m); Body Mass Index (Kg/m(2)): waist circumference (cm)] and biochemical [fasting blood glucose (mg/dl), TSH (µUI/mL), FT3 (pg/ml), FT4 (pg/ml), total, HDL and LDL-cholesterol (mg/dl), triglycerides (mg/dl)] evaluations. All patients underwent two-dimensional trans-thoracic echocardiographic evaluations in order to measure systolic (sPAP) and the end-diastolic pressure of the pulmonary artery (dPAP). There were no differences between the two populations regarding anthropometric and biochemical parameters. Patients with HT had higher sPAP values than controls (Hashimoto: 20.06 ± 6.56 mmHg vs controls: 19.96 ± 8.58 mmHg, p = 0.044). Patients with HT had lower dPAP values than controls (2.51 ± 0.90 mmHg vs. controls 3.17 ± 1.58 mmHg, p < 0.0001), and there was a statistically significant difference in the left ventricle ejection fraction between the two groups (60.57 ± 1.60 % in patients with HT vs. 61.04 ± 2.03 % in controls, p = 0.037). The multivariate regression analysis did not confirm such results. We demonstrated that patients with HT did not show relevant pulmonary hypertension when compared to healthy controls.