Mortality and Thyroid-Stimulating Hormone in Pulmonary Arterial Hypertension

Thyroid stimulating hormone (TSH) is linked with mortality among patients with pulmonary arterial hypertension (PAH), although no clear association exists between TSH and other markers of severity in patients with PAH, according to study findings published recently in BMJ Open Respiratory Research.

PAH affects heart function and vascular tone in some diseases, but little is known about the relationship between PAH and thyroid dysfunction. Researchers therefore investigated the association between thyroid-stimulating hormone (TSH) and clinical outcomes among individuals with PAH.

The researchers analyzed data from the Seattle Right Ventricle Translational Science (Servetus) Study, a prospective observational cohort that measured TSH levels in all participants between 2014 and 2016. Among participants, 112 had PAH. Linear regression was applied to estimate relationships between TSH and 6-minute walk distance, tricuspid annular plane systolic excursion, and right ventricular basal diameter, as well as the relationship between TSH and New York Heart Association Functional Classification. Cox proportional hazards were applied to estimate the relationship between FSH and mortality. Further analyses were also conducted that adjusted for birth sex, age, and etiology of pulmonary hypertension, with and without adjustment for N-terminal-pro hormone brain natriuretic peptide.

The researchers found that TSH was strongly associated with mortality among the 112 individuals with PAH, regardless of adjustments. No consistent link between TSH and other markers of severity was observed in this PAH cohort.

Researchers acknowledged significant limitations to the current study, including residual and unmeasured confounding, and lack of differentiation between subclinical thyroid dysfunction and overt thyroid disease in their analyses.

“This report reinforces the important observation that TSH is associated with survival in patients with PAH, and future study of thyroid dysfunction as a potential remediable contributor to mortality in PAH is warranted,” study authors concluded.

Reference

Pi H, Rayner SG, Ralph DD, et al. Thyroid-stimulating hormone and mortality in pulmonary arterial hypertension. BMJ Open Respir Res. July 2022;9(1):e001348. doi:10.1136/bmjresp-2022-001348