RATIONALE: Pulmonary hypertension (PH) commonly complicates idiopathic pulmonary fibrosis (IPF). However, the rate of change in pulmonary hemodynamics in IPF remains poorly defined. OBJECTIVES: To examine the rate of change in pulmonary hemodynamics among patients with IPF. METHODS: The rate of change in mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVR) was examined in patients with IPF listed for lung transplantation. The 5th and 7th World Symposium on Pulmonary Hypertension definitions for precapillary PH were employed in this analysis. MEASUREMENTS AND MAIN RESULTS: There were 496 patients with IPF that had at least two right heart catheterizations (RHCs) while listed for lung transplantation. The median time between repeated RHCs was 9 months (interquartile range [IQR]: 6-14). PH was present in 25.8% and 46.8% at the first RHC, while 42.9% and 64.3% had PH by the two definitions respectively, at the time of the final RHC. The median rate of change in the mPAP and PVR were 3.8 mmHg/year (IQR: -0.9-11.8) and 0.8 Wood Units/year (IQR: -0.2-2.4), respectively. The rate of PVR change was slower for those with established PH compared with those without PH. 28.6% of the patients had accelerated progression of their hemodynamics, arbitrarily defined as an increase in PVR of ≥ 2 Wood Units/year. CONCLUSIONS: PH associated with IPF tends to progress in an unpredictable fashion, with some patients demonstrating an accelerated phenotype. Among patients with RHC hemodynamics below the threshold for therapy, close vigilance is warranted with consideration for an early repeat RHC. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).