Abstract
There are limited published data defining survival and treatment response in patients with mild lung disease and/or reduced gas transfer who fulfil diagnostic criteria for idiopathic pulmonary arterial hypertension (IPAH).
Patients diagnosed with IPAH between 2001 and 2019 were identified in the ASPIRE (Assessing the Spectrum of Pulmonary Hypertension Identified at a Referral Centre) registry. Using prespecified criteria based on computed tomography (CT) imaging and spirometry, patients with a diagnosis of IPAH and no lung disease were termed IPAHno-LD (n=303), and those with minor/mild emphysema or fibrosis were described as IPAHmild-LD (n=190).
Survival was significantly better in IPAHno-LD than in IPAHmild-LD (1- and 5-year survival 95% and 70% versus 78% and 22%, respectively; p<0.0001). In the combined group of IPAHno-LD and IPAHmild-LD, independent predictors of higher mortality were increasing age, lower diffusing capacity of the lung for carbon monoxide (DLCO), lower exercise capacity and a diagnosis of IPAHmild-LD (all p<0.05). Exercise capacity and quality of life improved (both p<0.0001) following treatment in patients with IPAHno-LD, but not IPAHmild-LD. A proportion of patients with IPAHno-LD had a DLCO <45%; these patients had poorer survival than patients with DLCO ≥45%, although they demonstrated improved exercise capacity following treatment.
The presence of even mild parenchymal lung disease in patients who would be classified as IPAH according to current recommendations has a significant adverse effect on outcomes. This phenotype can be identified using lung function testing and clinical CT reports. Patients with IPAH, no lung disease and severely reduced DLCO may represent a further distinct phenotype. These data suggest that randomised controlled trials of targeted therapies in patients with these phenotypes are required.
Abstract
Patients with IPAH who have mild parenchymal lung disease have significantly worse outcomes, in terms of survival and treatment response, when compared to patients with IPAH who do not have evidence of parenchymal lung disease http://bit.ly/3agkYn0
Footnotes
This article has an editorial commentary: https://doi.org/10.1183/13993003.00606-2020
This article has supplementary material available from erj.ersjournals.com
Support statement: A.A.R. Thompson is supported by a British Heart Foundation Intermediate Clinical Fellowship (FS/18/13/3328). A.J. Swift is supported by a Wellcome Trust Clinical Research Career Development Fellowship (205188/Z/16/Z). Funding information for this article has been deposited with the Crossref Funder Registry.
Conflict of interest: R.A. Lewis reports non-financial support from Actelion Pharmaceuticals, outside the submitted work.
Conflict of interest: A.A.R. Thompson reports grants from British Heart Foundation, during the conduct of the study; support for meeting attendance from Actelion Pharmaceuticals Ltd, outside the submitted work.
Conflict of interest: C.G. Billings has nothing to disclose.
Conflict of interest: A. Charalampopoulos reports grants, personal fees and non-financial support from Actelion Pharmaceuticals, personal fees and non-financial support from Novartis, grants from Bayer and GSK, outside the submitted work.
Conflict of interest: C.A. Elliot reports personal fees for advisory board work and lectures from Actelion Pharmaceuticals, GlaxoSmithKline and Bayer, grants from Pfizer, Actelion Pharmaceuticals and Bayer, support for meeting attendance from Bayer and Actelion Pharmaceuticals, outside the submitted work.
Conflict of interest: N. Hamilton reports personal fees from MSD and Actelion, grants and personal fees from Bayer, outside the submitted work.
Conflict of interest: C. Hill has nothing to disclose.
Conflict of interest: J. Hurdman has nothing to disclose.
Conflict of interest: S. Rajaram has nothing to disclose.
Conflict of interest: I. Sabroe reports grants and personal fees for advisory board from AstraZeneca, grants from GSK, outside the submitted work.
Conflict of interest: A.J. Swift has nothing to disclose.
Conflict of interest: D.G. Kiely reports grants, personal fees and non-financial support from Actelion, Bayer and GSK, personal fees and non-financial support from MSD, outside the submitted work.
Conflict of interest: R. Condliffe reports grants, personal fees and non-financial support from Actelion Pharmaceuticals and Bayer, grants from GSK, outside the submitted work.
- Received December 4, 2019.
- Accepted February 16, 2020.
- Copyright ©ERS 2020
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