PT  - JOURNAL ARTICLE
AU  - Mathai, Stephen
AU  - Gashouta, Mohamed
AU  - Damico, Rachel
AU  - Hassoun, Paul
TI  - The impact of definition of ILD on WHO group Classification of PH in scleroderma
DP  - 2013 Sep 01
TA  - European Respiratory Journal
PG  - P2633
VI  - 42
IP  - Suppl 57
4099  - http://erj.ersjournals.com/content/42/Suppl_57/P2633.short
4100  - http://erj.ersjournals.com/content/42/Suppl_57/P2633.full
SO  - Eur Respir J2013 Sep 01; 42
AB  - Background:Patients with scleroderma (SSc) can develop several forms of pulmonary hypertension (PH). However, while guidelines for classification of PH distinguish between WHO Group I and II disease, they fail to distinguish between PH-ILD [group III] and PAH with thresholds of pulmonary function or chest radiographic findings that define PH-ILD. Therefore, we applied various definitions of “significant” ILD to our population of SSc patients with known PH to determine the impact on PH classification.Methods: 150 consecutive patients with SSc and either Group I or III PH documented by RHC were retrospectively reviewed. We applied 3 definitions of “significant” ILD:1) TLC<60% predicted or TLC 60-70% predicted with > “minimal” fibrosis (clinical trial definition)2) Limited/Extensive staging system: extent of lung involvement>20% of lung fields or <20% with FVC<70% predicted3) FVC<70% predicted.Patients were then reclassified as Group I or III based upon these criteria.Results: Using the clinical trial definition, 73% of patients had Group I disease; however, when applying the limited/extensive staging system or FVC criteria, only 39% patients had Group I disease. No differences in demographics or hemodynamics were noted between groups based upon ILD definition.Conclusions: We found a substantial impact upon the WHO group classification of patients with SSc-PH based upon criteria used to define ILD with changes in >40% of patients. Given the differences in response to therapy and outcomes in SSc between Group I and Group III disease, the changes in PH classification based upon definition of ILD demonstrated in this study have important implications for clinical trials and clinical practice.