Presence Of Interstitial Lung Abnormalities Research Articles

Postoperative pulmonary function of patients with lung cancer and interstitial lung abnormalities.

We investigated the impact of radiological interstitial lung abnormalities on the postoperative pulmonary functions of patients with non-small cell lung cancer. A total of 1191 patients with clinical stage IA non-small cell lung cancer who underwent lung resections and pulmonary function tests ≥ 6months postoperatively were retrospectively reviewed. Postoperative pulmonary function reduction rates were compared between patients with and without interstitial lung abnormalities and according to the radiological interstitial lung abnormality classifications. Surgical procedures were divided into wedge resection, 1-2 segment resection, and 3-5 segment resection groups. No significant differences in postoperative pulmonary function reduction rates 6months after wedge resection were observed between the interstitial lung abnormality [n = 202] and non-interstitial lung abnormality groups [n = 989] [vital capacity [VC]: 6.82% vs. 5.00%; forced expiratory volume in 1s [FEV1]: 7.05% vs. 7.14%]. After anatomical resection, these values were significantly lower in the interstitial lung abnormality group than in the non-interstitial lung abnormality group [VC: 1-2 segments, 12.50% vs. 9.93%; 3-5 segments, 17.42% vs. 14.23%; FEV1: 1-2 segments: 13.36% vs. 10.27%; 3-5 segments: 17.36% vs. 14.39%]. No significant differences in postoperative pulmonary function reduction rates according to the radiological interstitial lung abnormality classifications were observed. The presence of interstitial lung abnormalities had a minimal effect on postoperative pulmonary functions after wedge resections; however, pulmonary functions significantly worsened after segmentectomy or lobectomy, regardless of the radiological interstitial lung abnormality classification in early-stage non-small cell lung cancer.

Association between interstitial lung abnormality and mortality in patients with esophageal cancer.

To investigate the relationship between interstitial lung abnormalities (ILAs) and mortality in patients with esophageal cancer and the cause of mortality. This retrospective study investigated patients with esophageal cancer from January 2011 to December 2015. ILAs were visually scored on baseline CT using a 3-point scale (0 = non-ILA, 1 = indeterminate for ILA, and 2 = ILA). ILAs were classified into subcategories of non-subpleural, subpleural non-fibrotic, and subpleural fibrotic. Five-year overall survival (OS) was compared between patients with and without ILAs using the multivariable Cox proportional hazards model. Subgroup analyses were performed based on cancer stage and ILA subcategories. The prevalences of treatment complications and death due to esophageal cancer and pneumonia/respiratory failure were analyzed using Fisher's exact test. A total of 478 patients with esophageal cancer (age, 66.8years ± 8.6 [standard deviation]; 64 women) were evaluated in this study. Among them, 267 patients showed no ILAs, 125 patients were indeterminate for ILAs, and 86 patients showed ILAs. ILAs were a significant factor for shorter OS (hazard ratio [HR] = 1.68, 95% confidence interval [CI] 1.10-2.55, P = 0.016) in the multivariable Cox proportional hazards model adjusting for age, sex, smoking history, clinical stage, and histology. On subgroup analysis using patients with clinical stage IVB, the presence of ILAs was a significant factor (HR = 3.78, 95% CI 1.67-8.54, P = 0.001). Subpleural fibrotic ILAs were significantly associated with shorter OS (HR = 2.22, 95% CI 1.25-3.93, P = 0.006). There was no significant difference in treatment complications. Patients with ILAs showed a higher prevalence of death due to pneumonia/respiratory failure than those without ILAs (non-ILA, 2/95 [2%]; ILA, 5/39 [13%]; P = 0.022). The prevalence of death due to esophageal cancer was similar in patients with and without ILA (non-ILA, 82/95 [86%]; ILA 32/39 [82%]; P = 0.596). ILAs were significantly associated with shorter survival in patients with esophageal cancer.

Quantitative assessment of airway wall thickness in COPD patients with interstitial lung abnormalities.

Whether the airway is involved in the pathogenesis of interstitial lung abnormalities (ILA) is not well understood. Also the impact of ILA on lung function in COPD patients remains controversial. We aimed to assess the quantitative CT measurements of airway wall thickness (AWT) and lung function according to ILA status in COPD patients. 157 COPD patients discharged from our hospital from August 1, 2019 through August 31, 2022 who underwent chest CT imagings and pulmonary function tests were retrospectively enrolled. Linear regression analysis and multiple models were used to analyze associations between quantitative assessment of airway wall changes and the presence of ILA. In 157 COPD patients, 23 patients (14.6%) had equivocal ILA, 42 patients (26.8%) had definite ILA. The definite ILA group had the highest measurements of Pi10 (square root of theoretical airway wall area with a lumen perimeter of 10 mm), segmental AWT and segmental WA% (percentage of wall area), whereas the no ILA group had the lowest measurements of Pi10, segmental AWT and segmental WA%. In the adjusted analyses (adjusted by age, sex, body mass index, smoking intensity, COPD GOLD stage, lung function, slice thickness and scanner type), compared to COPD patients without ILA, the measurements of Pi10, segmental AWT and segmental WA% were higher in definite ILA group with differences of 0.225 mm (p = 0.012), 0.152 mm (p < 0.001), 4.8% (p < 0.001) respectively. COPD patients with definite ILA tended to have higher FEV1% predicted, FVC% predicted and lower MMEF75/25% predicted, but there were no statistically differences among the three groups. Our study demonstrates the higher AWT measures in COPD patients with ILA compared to the patients without ILA. These findings suggest that the airway may be involved in the pathogenesis of ILA.

Association of pretreatment chest CT abnormalities with trastuzumab deruxtecan–associated pneumonitis.

1106 Background: Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate approved for HER2+ metastatic breast cancer (MBC) and HER2-low (IHC 1+ or 2+ with FISH-) MBC . Pneumonitis with T-DXd has been observed in 13.6% of patients (pts) on DESTINY-Breast 01 (including 2.2% fatal events) and 12.1% in pts on DESTINY-BREAST 04 (including 0.8% fatal events). There is an unmet need to determine if pts with baseline lung abnormalities are at increased risk for development of pneumonitis from T-DXd. Methods: This retrospective cohort study included all pts treated with T-DXd for MBC at an academic institution from 1/2020 to 2/2023 for more than 1 cycle (&gt;21 days). Outcomes were evaluated from treatment initiation until 2/1/2023. Two board-certified radiologists blinded to outcomes reviewed staging chest CTs performed before initiating T-DXd and graded each scan on 16 parenchymal abnormalities, including presence of interstitial lung abnormalities (ILA). Pneumonitis was retrospectively adjudicated by an independent oncologist using chart review and graded according to CTCAE v5.0 and compared to the treating physician’s assessment. The difference of proportions was analyzed with the Pearson Chi-Square test. Significance was declared at the 0.05 type I error threshold. Results: A total of 68 pts (median age 57.3 years) were included (30 = HER2+, 24 = HR+/HER2 low, 14 = TNBC/HER2 low). By independent assessment, 16 pts (23.5%) had grade 1 pneumonitis and 3 pts (4.4%) grade 2 pneumonitis. Median time from treatment initiation to pneumonitis was 83 days (range 35-266). By treating physician assessment, 5 pts (7.4%) developed grade 1 pneumonitis and 3 pts (4.4%) developed grade 2 pneumonitis. 16 of 68 pts (23.5%) had baseline ILA and 62 pts (91.2%) had at least one other parenchymal abnormality. As assessed by an independent oncologist, of pts with baseline ILA (N = 16), 12.5% developed T-DXd related pneumonitis, compared to 32.7% of pts without pre-existing ILA (N=52), p=0.16. There was no statistical difference in T-DXd related pneumonitis assessed by treating physician between pts with baseline ILA (2/16 patients, 12.5%) compared to pts without baseline ILA (7/52 pts, 13.5%), p=0.68. Conclusions: In this study, presence of baseline ILA was not associated with subsequent pneumonitis from T-DXd. Notably, the rate of independently assessed pneumonitis was higher than treatment-attributed pneumonitis as defined by the treating physician. Further research is needed to validate these findings and define predictors of treatment-associated pneumonitis. [Table: see text]

Interstitial lung abnormalities: Real‐world evidence

Interstitial lung abnormalities: Real‐world evidence

Pre-Existing Interstitial Lung Abnormalities Are Independent Risk Factors for Interstitial Lung Disease during Durvalumab Treatment after Chemoradiotherapy in Patients with Locally Advanced Non-Small-Cell Lung Cancer.

Chemoradiotherapy (CRT) followed by durvalumab, an immune checkpoint inhibitor, is the standard treatment for locally advanced non-small-cell lung cancer (NSCLC). Interstitial lung disease (ILD) is a life-threatening toxicity caused by these treatments; however, risk factors for the ILD have not yet been established. Interstitial lung abnormalities (ILAs) are computed tomography (CT) findings which manifest as minor interstitial shadows. We aimed to investigate whether ILAs could be risk factors for grade-two or higher ILD during durvalumab therapy. Patients with NSCLC who received durvalumab after CRT from July 2018 to June 2021 were retrospectively enrolled. We obtained patient characteristics, laboratory data, radiotherapeutic parameters, and chest CT findings before durvalumab therapy. A total of 148 patients were enrolled. The prevalence of ILAs before durvalumab treatment was 37.8%. Among 148 patients, 63.5% developed ILD during durvalumab therapy. The proportion of patients with grade-two or higher ILD was 33.8%. The univariate logistic regression analysis revealed that older age, high dose-volume histogram parameters, and the presence of ILAs were significant risk factors for grade-two or higher ILD. The multivariate analysis showed that ILAs were independent risk factors for grade-two or higher ILD (odds ratio, 3.70; 95% confidence interval, 1.69-7.72; p &lt; 0.001). We showed that pre-existing ILAs are risk factors for ILD during durvalumab treatment after CRT. We should pay attention to the development of grade-two or higher ILD during durvalumab treatment in patients with ILAs.

Pre-existing interstitial lung abnormalities are independent risk factors for interstitial lung disease during durvalumab treatment after chemoradiotherapy in patients with locally advanced non–small lung cancer.

8528 Background: The standard treatment for locally advanced non-small cell lung cancer (NSCLC) is chemoradiotherapy (CRT) followed by treatment of durvalumab, one of immune checkpoint inhibitors (ICI). Interstitial lung disease (ILD) is a clinically life-threatening toxicity of CRT or durvalumab. The patient-characteristics or dose-volume histogram parameters of radiotherapy have been reported to be the risk factors for radiation-induced pneumonitis. However, the risk factors for ILD during durvalumab therapy has not been established. Interstitial lung abnormalities (ILA) are generated by aging or smoking, and manifest as minor interstitial shadow on lung computed tomography (CT). We previously reported that ILA were risk factors for ICI-induced ILD in patients with advanced NSCLC, as well as non-lung cancer. Therefore, we investigated whether ILA could be risk factors for ILD during the durvalumab therapy. Methods: We retrospectively enrolled NSCLC patients who received durvalumab after CRT at 10 institutions from July 2018 to June 2021. Patient-information, patient-characteristics, dose-volume histogram parameters, chest CT findings, and laboratory data, were obtained. CT findings were examined using CT obtained after CRT and prior to durvalumab therapy. Results: A total of 153 patients were enrolled, and the prevalence of ILA was 37.8% (56 patients) before durvalumab treatment. Among the enrolled patients, 94 (63.5%) developed ILD during durvalumab therapy. The proportion of patients with grade 1, grade 2, or grade 3 ILD was observed to be 29.7% (44 patients), 25.7% (38 patients), and 8% (12 patients), respectively. Univariate logistic regression analysis revealed that higher age, higher dose volume histogram parameters (V5, V20, mean lung dose), and the presence of ILA were significant risk factors for grade 2 or more ILD. Multivariate logistic regression analysis showed that ILA, especially ground grass attenuation in ILA, was an independent risk factor for grade 2 or more ILD (odds ratio: 7.02, 95% CI: 2.95-16.69, p &lt; 0.0001). Conclusions: Pre-existing ILA are risk factors for ILD during durvalumab treatment after CRT. This observation is consistent with previously reported findings in patients with advanced lung cancer and non-lung cancer. Therefore, we should pay more attention to the development of grade 2 or more ILD during durvalumab treatment in patients with ILA.

Chronic Obstructive Pulmonary Disease Combined with Interstitial Lung Disease.

Although chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD) have distinct clinical features, both diseases may coexist in a patient because they share similar risk factors such as smoking, male sex, and old age. Patients with both emphysema in upper lung fields and diffuse ILD are diagnosed with combined pulmonary fibrosis and emphysema (CPFE), which causes substantial clinical deterioration. Patients with CPFE have higher mortality compared with patients who have COPD alone, but results have been inconclusive compared with patients who have idiopathic pulmonary fibrosis (IPF). Poor prognostic factors for CPFE include exacerbation, lung cancer, and pulmonary hypertension. The presence of interstitial lung abnormalities, which may be an early or mild form of ILD, is notable among patients with COPD, and is associated with poor prognosis. Various theories have been proposed regarding the pathophysiology of CPFE. Biomarker analyses have implied that this pathophysiology may be more closely associated with IPF development, rather than COPD or emphysema. Patients with CPFE should be advised to quit smoking and undergo routine lung function tests, and pulmonary rehabilitation may be helpful. Various pharmacologic agents and surgical approaches may be beneficial in patients with CPFE, but further studies are needed.

Chronic obstructive pulmonary disease combined with interstitial lung disease.

Although chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD) have distinct clinical features, both diseases may coexist in a patient because they share similar risk factors such as smoking, male sex, and old age. Patients with both emphysema in upper lung fields and diffuse ILD are diagnosed with combined pulmonary fibrosis and emphysema (CPFE), which causes substantial clinical deterioration. Patients with CPFE have higher mortality compared with patients who have COPD alone, but results have been inconclusive compared with patients who have idiopathic pulmonary fibrosis (IPF). Poor prognostic factors for CPFE include exacerbation, lung cancer, and pulmonary hypertension. The presence of interstitial lung abnormalities, which may be an early or mild form of ILD, is notable among patients with COPD, and is associated with poor prognosis. Various theories have been proposed regarding the pathophysiology of CPFE. Biomarker analyses have implied that this pathophysiology may be more closely associated with IPF development, rather than COPD or emphysema. Patients with CPFE should be advised to quit smoking and undergo routine lung function tests, and pulmonary rehabilitation may be helpful. Various pharmacologic agents and surgical approaches may be beneficial in patients with CPFE, but further studies are needed.

PREVALENCE OF INTERSTITIAL LUNG ABNORMALITIES AND ASSOCIATION WITH MORTALITY AND HOSPITALIZATION IN A CT LUNG CANCER SCREENING COHORT

TOPIC: Diffuse Lung Disease TYPE: Original Investigations PURPOSE: Interstitial lung abnormalities (ILA), non-dependent interstitial changes identified on lung CT scans, have been shown to have significant biological and clinical consequences. In some cases, ILA may represent a less severe or earlier stage of pulmonary fibrosis. In the United States, 14.5 million patients are estimated to be eligible for CT lung cancer screening (CTLS) which has the potential to be an early screening tool for interstitial lung disease. In this study, we sought to characterize ILA in a large CTLS cohort, evaluating prevalence and associations with clinically relevant outcomes. METHODS: Patients (n=1703) from Lahey Hospital and Medical Center who underwent CTLS from Jan 12, 2012 through Sep 30, 2014 and had an in network primary care physician were included; outcomes data was collected through Sep 30, 2019. Two thoracic radiologists certified in lung cancer screening scored the baseline CT exams per Fleischner Society ILA position paper guidelines (ILA, indeterminate, no ILA). For CT scans in which the score was discordant between the two radiologists (n=163), a third reader scored the CT to determine the final score. Cox multivariable regression proportional hazards models were used to test the association between ILA and cancer, all-cause mortality, all cause hospitalization and COPD and pneumonia related hospital admission adjusted for age, sex, smoking status and pack years exposure. Kaplan-Meier plots were generated to visualize the associations between observed baseline ILA and clinical outcomes. To adjust for multiplicity Bonferroni correction was utilized and p-value significance was set at<=0.01. All statistical analyses were performed using STATA14.1. RESULTS: Baseline characteristics were mean age 62.6 ± 6.2 years, 56.3% male, 57.7% with emphysema. A total of 101 (5.9%) patients were scored indeterminate and 45 (2.6%) were scored for ILA on the baseline CT. Of those with ILA, 35 (78%) had not been seen by a pulmonologist prior to their baseline CT and average time between baseline CTLS exam and referral was 2.51 ± 2.85 years. Of the patients with baseline ILA, who did not carry a pre-scan diagnosis of interstitial lung disease (ILD) (n=39), 15(33.3%) subsequently received a clinical diagnosis of ILD, 5.0 ± 2.5 years post baseline scan. In multivariable modeling, the presence of ILA was associated with death, HR 4.05 (2.26, 7.23, p<0.001) and hospital admission for pneumonia, HR 3.07 (1.41, 6.68, p<0.005). CONCLUSIONS: The results of this study demonstrate that ILA are a significant clinical finding in a large CTLS cohort with a prevalence and 5-year mortality risk similar to that of lung cancer. A significant percentage of these patients develop clinical ILD and may benefit from early pulmonology referral, evaluation, and management. CLINICAL IMPLICATIONS: Identification of ILA in a CTLS cohort has the potential to identify patients who will develop clinical ILD. DISCLOSURES: No relevant relationships by Melissa Gawlik, source=Web Response Grant funding relationship with Genentech Please note: 9/10/2020 Added 04/23/2021 by Lee Gazourian, source=Web Response, value=Grant/Research Support No relevant relationships by Jeffrey Hashim, source=Web Response No relevant relationships by Gary Hunninghake, source=Web Response Advisor relationship with AstraZeneca Please note: 2019-2021 Added 04/22/2021 by Brady McKee, source=Web Response, value=Advisor Fee No relevant relationships by Timothy MD, source=Web Response No relevant relationships by Ezra Miller, source=Web Response Grant recipient relationship with Genentech Please note: 07/01/2020 -- Added 04/18/2021 by Avignat Patel, source=Web Response, value=Grant/Research Support No relevant relationships by Lori Lyn Price, source=Web Response No relevant relationships by Shawn Regis, source=Web Response No relevant relationships by Christoph Wald, source=Web Response, value=Honoraria Removed 04/22/2021 by Christoph Wald, source=Web Response

The impact of lung parenchyma attenuation on nodule volumetry in lung cancer screening

BackgroundRecent recommendations for lung nodule management include volumetric analysis using tools that present intrinsic measurement variability, with possible impacts on clinical decisions and patient safety. This study was conducted to evaluate whether changes in the attenuation of the lung parenchyma adjacent to a nodule affect the performance of nodule segmentation using computed tomography (CT) studies and volumetric tools.MethodsTwo radiologists retrospectively applied two commercially available volumetric tools for the assessment of lung nodules with diameters of 5–8 mm detected by low-dose chest CT during a lung cancer screening program. The radiologists recorded the success and adequacy of nodule segmentation, nodule volume, manually and automatically (or semi-automatically) obtained long- and short-axis measurements, mean attenuation of adjacent lung parenchyma, and presence of interstitial lung abnormalities or disease, emphysema, pleural plaques, and linear atelectasis. Regression analysis was performed to identify predictors of good nodule segmentation using the volumetric tools. Interobserver and intersoftware agreement on good nodule segmentation was assessed using the intraclass correlation coefficient.ResultsIn total, data on 1265 nodules (mean patient age, 68.3 ± 5.1 years; 70.2% male) were included in the study. In the regression model, attenuation of the adjacent lung parenchyma was highly significant (odds ratio 0.987, p < 0.001), with a large effect size. Interobserver and intersoftware agreement on good segmentation was good, although one software package performed better and measurements differed consistently between software packages.ConclusionFor lung nodules with diameters of 5–8 mm, the likelihood of good segmentation declines with increasing attenuation of the adjacent parenchyma.

Prevalence of and risk factors for pulmonary complications after curative resection in otherwise healthy elderly patients with early stage lung cancer

Background and objectiveThe prevalence of lung cancer has been increasing in healthy elderly patients with preserved pulmonary function and without underlying lung diseases. We aimed to determine the prevalence of and risk factors for postoperative pulmonary complications (PPCs) in healthy elderly patients with non-small cell lung cancer (NSCLC) to select optimal candidates for surgical resection in this subpopulation.MethodsWe included 488 patients older than 70 years with normal spirometry results who underwent curative resection for NSCLC (stage IA-IIB) between 2012 and 2016.ResultsThe median (interquartile range) age of our cohort was 73 (71–76) years. Fifty-two patients (10.7%) had PPCs. Severe PPCs like acute respiratory distress syndrome, pneumonia, and respiratory failure had prevalences of 3.7, 3.7, and 1.4%, respectively. Compared to patients without PPCs, those with PPCs were more likely to be male and current smokers; have a lower body mass index (BMI), higher American Society of Anesthesiologists (ASA) classification, more interstitial lung abnormalities (ILAs), and higher emphysema index on computed tomography (CT); and have undergone pneumonectomy or bilobectomy (all p < 0.05). On multivariate analysis, ASA classification ≥3, lower BMI, ILA, and extent of resection were independently associated with PPC risk. The short-term all-cause mortality was significantly higher in patients with PPCs.ConclusionsCurative resection for NSCLC in healthy elderly patients appeared feasible with 10% PPCs. ASA classification ≥3, lower BMI, presence of ILA on CT, and larger extent of resection are predictors of PPC development, which guide treatment decision-making in these patients.

Serum 25-Hydroxyvitamin D Concentrations Are Associated with Computed Tomography Markers of Subclinical Interstitial Lung Disease among Community-Dwelling Adults in the Multi-Ethnic Study of Atherosclerosis (MESA)

BackgroundActivated vitamin D has anti-inflammatory properties. 25-Hydroxyvitamin D [25(OH)D] deficiency might contribute to subclinical interstitial lung disease (ILD). ObjectiveWe examined associations between serum 25(OH)D concentrations and subclinical ILD among middle-aged to older adults who were free of cardiovascular disease at baseline. MethodsWe studied 6302 Multi-Ethnic Study of Atherosclerosis (MESA) participants who had baseline serum 25(OH)D concentrations and computed tomography (CT) imaging spanning ≤ 10 y. Baseline cardiac CT scans (2000–2002) included partial lung fields. Some participants had follow-up cardiac CT scans at exams 2–5 and a full-lung CT scan at exam 5 (2010–2012), with a mean ± SD of 2.1 ± 1.0 scans. Subclinical ILD was defined quantitatively as high-attenuation areas (HAAs) between –600 and –250 Hounsfield units. We assessed associations of 25(OH)D with adjusted HAA volumes and HAA progression. We also examined associations between baseline 25(OH)D and the presence of interstitial lung abnormalities (ILAs) assessed qualitatively (yes or no) from full-lung CT scans at exam 5. Models were adjusted for sociodemographic characteristics, lifestyle factors (including smoking), and lung volumes. ResultsThe cohort's mean ± SD characteristics were 62.2 ± 10 y for age, 25.8 ± 10.9 ng/mL for 25(OH)D concentrations, and 28.3 ± 5.4 for body mass index (kg/m2); 53% were women, with 39% white, 27% black, 22% Hispanic, and 12% Chinese race/ethnicities. Thirty-three percent had replete (≥30 ng/mL), 35% intermediate (20 to <30 ng/mL), and 32% deficient (<20 ng/mL) 25(OH)D concentrations. Compared with those with replete concentrations, participants with 25(OH)D deficiency had greater adjusted HAA volume at baseline (2.7 cm3; 95% CI: 0.9, 4.5 cm3) and increased progression over a median of 4.3 y of follow-up (2.7 cm3; 95% CI: 0.9, 4.4 cm3) (P < 0.05). 25(OH)D deficiency was also associated with increased prevalence of ILAs 10 y later (OR: 1.5; 95% CI: 1.1, 2.2). ConclusionsVitamin D deficiency is independently associated with subclinical ILD and its progression, based on both increased HAAs and ILAs, in a community-based population. Further studies are needed to examine whether vitamin D repletion can prevent ILD or slow its progression. The MESA cohort design is registered at www.clinicaltrials.gov as NCT00005487.

Functional Impact of a Spectrum of Interstitial Lung Abnormalities in Rheumatoid Arthritis

Approximately 10% of patients with rheumatoid arthritis (RA) have interstitial lung disease (ILD), and one-third have subclinical ILD on chest CT scan. In this study, we aimed to further characterize functional decrements in a spectrum of RA-associated ILD. All subjects were enrolled in the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS). The presence of interstitial lung abnormalities (ILAs) on clinically indicated chest CT scans was determined using a previously validated sequential reading method. Univariate and multivariate analyses were used to assess the association between degree of ILAs and physiologic, functional, and demographic variables of interest. Of 1,145 BRASS subjects, 91 subjects (8%) were included in this study. Twelve had radiologically severe ILAs, 34 had ILAs, and 38 had no ILAs on CT scan. Subjects with radiologically severe ILAs were older (P = .0037), had increased respiratory symptoms (cough, P = .027; dyspnea, P = .010), and more severe RA disease (rheumatoid factor, P = .018; total swollen joints, P = .046) compared with subjects with no ILAs. Participants also had a trend toward having an increased smoking history (P = .16) and having lower FVC % predicted (77% vs 94%, P = .097) and diffusion capacity of carbon monoxide % predicted (52% vs 77%, P = .068). Similar but attenuated increases in respiratory symptoms, functional decrements, and RA disease severity were observed in subjects with ILAs compared with those with no ILAs. We have shown that patients with RA have varying degrees of ILAs that are associated with a spectrum of functional and physiologic decrements. Our findings suggest that improved risk stratification and detection of ILAs will provide a therapeutic window that could improve RA-ILD outcomes.

Detection of subtle interstitial abnormalities of the lungs on digitized chest radiographs: acceptable data compression ratios.

To determine acceptable compression ratios for digital radiography, we evaluated the effect of data compression on the detection of subtle interstitial lung abnormalities using digitized chest radiographs. Screen-film chest radiographs of 38 patients with subtle interstitial lung abnormalities and 40 patients with normal lung parenchyma were digitized (spatial resolution, 0.175 mm; 2000 x 2000 pixels; 10 bits per pixel) and compressed with the discrete cosine transform method at ratios of 10:1, 20:1, and 30:1. Five chest radiologists and five radiology residents examined the uncompressed and compressed digital images and rates the presence of interstitial lung abnormalities with a five-level scale of confidence. Results were analyzed by receiver operating characteristic methods. Overall, the interpretation of images with a compression ratio of 30:1 was significantly less accurate than that of uncompressed images (p < .05). For the five chest radiologists, interpretation of images with a compression ratio of 20:1 or 30:1 was significantly less accurate than that of uncompressed images (p < .05). However, for the five residents, no significant difference between interpretations of compressed and uncompressed images was noted (p > or = .05). These results suggest that a 10:1 data compression ratio does not influence the detection of subtle interstitial lung abnormalities. However, information that is lost with a 20:1 data compression ratio might be essential for interpretation by experienced chest radiologists.