Introduction: Despite the poor prognosis of interstitial lung disease (ILD) with pulmonary hypertension (PH), evidence-based guidelines for PH screening in ILD are lacking. PHINDER (NCT05776225) aims to develop a validated PH screening tool in patients with ILD.

Objectives: This PHINDER interim analysis evaluated which clinical features among ILD patients were associated with the presence of PH.

Materials and Methods: PHINDER is a prospective, multicenter study enrolling approximately 300 patients with ILD who undergo non-invasive clinical assessments – including physical exam, pulmonary function tests, echocardiography, and chest computed tomography – followed by right heart catheterization (RHC) to confirm the presence of PH. An interim univariate logistic regression analysis was performed on numerous variables from each assessment to determine their association with the presence of PH, defined as a mean pulmonary arterial pressure (mPAP) >20 mmHg, compared to patients with mPAP ≤20 mmHg.

Results: Data were available for 190 patients (median age 73 years, median time since ILD diagnosis 2.5 years, 54% male, 57% with IIPs and 23% with CTD-ILD), 134 (71%) of which had mPAP >20 mmHg on RHC. Supplemental O2 use and rate, B-type and N-terminal pro B-type natriuretic peptide levels, DLCO absolute and % predicted, FVC/DLCO ratio, right ventricle systolic pressure (RVSP), tricuspid regurgitant velocity (TRV), tricuspid annular plane systolic excursion (TAPSE)/RVSP ratio, RV/LV ratio, pulmonary artery (PA)/aorta ratio, and PA enlargement were found to be statistically associated with mPAP >20 mmHg (Table 1).

Conclusions: Clinical characteristics including supplemental oxygen requirements, natriuretic peptide levels, DLCO, RVSP, TRV, PA diameter, and RV/LV ratio, may indicate the presence of elevated mPAP in patients with ILD. Results of the fully enrolled PHINDER study will further refine and expand upon these results to develop a validated, practical tool for PH screening in ILD.