The aim of this study was to assess the frequency and prognostic significance of PH in our patients with ILD.
Patients with a diagnosis of ILD and who had been assessed for PH at Ege University Hospital between 2009 and 2016 were reviewed.
The study population is 672 patients referred with ILD who were investigated for pulmonary hypertension (PH), 260 were male, 412 were female. The mean age was 56 years (range 13 to 86). The diagnoses included a wide range of interstitial lung diseases. The mean follow up from presentation was 50 months (range 1 to 206), during which time 145 patients (22%) died. All patients had echocardiography. The mean SPAP value was 42 mmHg (range 10 to 130). By Cox Regression analysis, the SPAP value is a strong predictor of survival (p<0.001). On Kaplan-Meier survival analysis, mean survival from first presentation for those (n=488) with an SPAP ≤ 35 mmHg on echo was 161 months (95% CI 145 to 176), compared to 78 months (95% CI 62 to 95) for those (n=184) with an SPAP > 35 mmHg (p<0.001). 83 patients went on to right heart catheterisation (RHC) of whom 52 were found to have PH. ROC analyses were performed to investigate possible predictors of PH on RHC. The areas under the curve were: pulmonary artery diameter; 0.728, pulmonary artery/aorta ratio; 0.676, pulmonary artery /vertebral body ratio; 0.680, SPAP > 35 mmHg; 0.702, TVR on ECHO; 0.687, brain naturetic peptide; 0.729; FVC%/DLCO% ratio; 0.663.
Assessment of pulmonary pressure is of prognostic value in the broad spectrum of patients with ILD. SPAP is a non-invasive method applicable to all patients and yields a statistically significant stratification of patients. Pulmonary artery diameter, BNP and SPAP predict PH by RHC.
Clinicians need to be aware of risk of PH in ILD and to appropriately investigate. The development of PH has a significant impact on survival.