Smoking-Related Interstitial Fibrosis: Evidence of Radiologic Regression with Advancing Age and Smoking Cessation.

More data are needed regarding the radiology, co-morbidities and natural history of smoking-related interstitial fibrosis (SRIF), a common pathological finding, mainly described heretofore in association with lung cancer, where respiratory bronchiolitis (RB) usually co-exists. We prospectively acquired high resolution CT scan data (edge-enhancing lung reconstructions) to detect any radiologic interstitial lung abnormality (ILA) in individuals who ultimately underwent surgical lobectomy for lung cancer (n = 20), for radiologic/pathologic correlation. We also re-examined other smoking-related benign histologic cases: chronic obstructive pulmonary disease (COPD lung explants, n = 20), alpha 1-antitrypsin deficiency (A1AT, explanted lungs n = 20), combined pulmonary fibrosis and emphysema (CPFE, n = 8) and idiopathic pulmonary fibrosis (IPF, n = 10). Finally, we pooled our data with all peer-reviewed published data describing histologic SRIF of known ILA status. SRIF was observed in 40% of cancer lobectomies, mean (±SD) age 65.8 ± 8.7 years, none of whom had ILA. SRIF was observed in other smoking-related benign diseases (COPD 35%, A1AT 20%, CPFE 25%, and IPF 10%). 71.4% of benign SRIF cases had no RB (nearly all ex-smokers) versus 0% of cancer-associated SRIF cases (P = 1.7 × 10-3). Pooled data showed that those SRIF subjects without ILA were 15.05 years older than those with ILA (95% confidence interval 8.99 to 21.11, P = 2.5 × 10-5) and more likely to be former smokers (P = 7.2 × 10-3). SRIF is frequently found without lung cancer, and mostly without RB in former smokers. SRIF is less likely to have ILA in older subjects and with smoking cessation, which could represent RB+/-SRIF regression.

Pulmonary hypertension in idiopathic pulmonary fibrosis with mild-to-moderate restriction.

The clinical course of pulmonary hypertension (PH) in idiopathic pulmonary fibrosis (IPF) is not known except in advanced disease.488 subjects in a placebo-controlled study of ambrisentan in IPF with mild-moderate restriction in lung volume, underwent right heart catheterisation (RHC) at baseline and 117 subjects (24%) had repeated haemodynamic measurements at 48 weeks. The subjects were categorised into a) World Health Organization (WHO) Group 3 PH (PH associated with pulmonary disease), n=68 (14%); b) WHO Group 2 PH (PH associated with left-sided cardiac disease), n=25 (5%); c) no PH but elevated pulmonary artery wedge pressure (PAWP), n=21 (4%); and d) no PH but without elevation of PAWP, n=374 (77%). The WHO Group 3 PH subjects had a lower diffusion capacity, 6MWD and oxygen saturation compared to the subjects with no PH. There was no significant change in mean pulmonary arterial pressure with ambrisenten or placebo after 12 months. Subjects with IPF associated with WHO Group 3 PH had impaired gas exchange and exercise capacity compared to patients without PH. An additional 9% of the subjects had haemodynamic evidence of subclinical left-ventricular dysfunction. Pulmonary artery pressures remained stable over 1 year in the majority of the cohort.

Diagnosis of idiopathic pulmonary fibrosis with high-resolution CT in patients with little or no radiological evidence of honeycombing: secondary analysis of a randomised, controlled trial.

BACKGROUND: Present guidelines for the diagnosis of idiopathic pulmonary fibrosis require histological confirmation of surgical lung biopsy samples when high-resolution CT images are not definitive for usual interstitial pneumonia. We aimed to assess the predictive value of high-resolution CT in a cohort of patients with suspected idiopathic pulmonary fibrosis from a previous randomised trial. METHODS: ARTEMIS-IPF was a randomised, double-blind, placebo-controlled, multicentre, phase 3 trial of ambrisentan for adults aged 40-80 years with well-defined idiopathic pulmonary fibrosis and 5% or less honeycombing on high-resolution CT. In December, 2010, an interim analysis showed lack of efficacy and the trial was stopped. In the present follow-on analysis, we assessed patients who were screened for ARTEMIS-IPF who underwent high-resolution CT as part of screening and surgical lung biopsy as part of standard clinical care. A radiologist and a pathologist from a central panel independently assessed anonymised CT scans and biopsy samples. We calculated the positive and negative predictive value of high-resolution CT (classified as usual interstitial pneumonia, possible usual interstitial pneumonia, and inconsistent with usual interstitial pneumonia) for confirmation of histological patterns of usual interstitial pneumonia. This study is registered with ClinicalTrials.gov, number NCT00768300. FINDINGS: 315 (29%) of 1087 consecutively screened patients in ARTEMIS-IPF had both high-resolution CT and surgical lung biopsy samples. 108 of 111 patients who met high-resolution CT criteria for usual interstitial pneumonia had histologically confirmed usual interstitial pneumonia (positive predictive value 97·3%, 95% CI 92·3-99·4), as did 79 of 84 patients who met high-resolution CT criteria for possible usual interstitial pneumonia (94·0%, 86·7-98·0). 22 of 120 patients had an inconsistent high-resolution CT pattern for usual interstitial pneumonia that was histologically confirmed as not or possible usual interstitial pneumonia (negative predictive value 18·3%, 95% CI 11·9-26·4). INTERPRETATION: In the appropriate clinical setting, for patients with possible usual interstitial pneumonia pattern on high resolution CT, surgical lung biopsy sampling might not be necessary to reach a diagnosis of idiopathic pulmonary fibrosis if high-resolution CT scans are assessed by experts at regional sites familiar with patterns of usual interstitial pneumonia and management of idiopathic interstitial pneumonia. FUNDING: Gilead Sciences.