Clinical features and long-term survival in idiopathic pulmonary arterial hypertension with thyroid dysfunction: insights from a national multicentre prospective study

Abstract

ObjectiveTo clarify the characteristics and long-term survival of idiopathic pulmonary arterial hypertension patients with thyroid dysfunction (IPAH-TD), and compare them with IPAH without thyroid dysfunction.MethodsA retrospective analysis was conducted using prospectively collected data. IPAH patients with thyroid dysfunction at baseline were included. Patients with other subgroups of PAH and Group 2–5 pulmonary hypertension were excluded. IPAH patients with euthyroid function were matched 1:1 to IPAH-TD by age and sex.ResultsIn total, 148 IPAH patients with thyroid dysfunction were included. Patients with hyper/hypothyroidism and subclinical hyper/hypothyroidism accounted for 16.2%, 18.9%, 8.1%, and 56.8%, respectively. IPAH patients with hyperthyroidism showed the highest mixed venous oxygen saturation (SvO2) and the lowest pulmonary vascular resistance (PVR) at baseline among subgroups, while patients with subclinical hypothyroidism had the lowest SvO2and highest PVR (p<0.05). Compared with IPAH without thyroid dysfunction, patients with hyperthyroidism (9.14 WUversus13.86 WU, p<0.05) and hypothyroidism (10.7 WUversus13.86 WU, p<0.05) showed significantly lower PVR. The hemodynamic profiles of patients with subclinical hypothyroidism were similar to IPAH with euthyroid function except for lower RAP (6 mmHgversus8 mmHg, p=0.009). The long-term survival of patients with clinical thyroid dysfunction was better than IPAH without thyroid dysfunction, while that of those with subclinical diseases was comparable to the latter, even after adjusting for baseline hemodynamics and treatment.ConclusionIPAH patients with clinical hyper- and hypothyroidism had better hemodynamics and survival than those without thyroid dysfunction, while patients with subclinical hypothyroidism had similar above profiles to the latter.