Patient-centered Outcomes Research in Interstitial Lung Disease: An Official American Thoracic Society Research Statement.

Background: In the past two decades, many advances have been made to our understanding of interstitial lung disease (ILD) and the way we approach its treatment. Despite this, many questions remain unanswered, particularly those related to how the disease and its therapies impact outcomes that are most important to patients. There is currently a lack of guidance on how to best define and incorporate these patient-centered outcomes in ILD research. Objectives: To summarize the current state of patient-centered outcomes research in ILD, identify gaps in knowledge and research, and highlight opportunities and methods for future patient-centered research agendas in ILD. Methods: An international interdisciplinary group of experts was assembled. The group identified top patient-centered outcomes in ILD, reviewed available literature for each outcome, highlighted important discoveries and knowledge gaps, and formulated research recommendations. Results: The committee identified seven themes around patient-centered outcomes as the focus of the statement. After a review of the literature and expert committee discussion, we developed 28 research recommendations. Conclusions: Patient-centered outcomes are key to ascertaining whether and how ILD and interventions used to treat it affect the way patients feel and function in their daily lives. Ample opportunities exist to conduct additional work dedicated to elevating and incorporating patient-centered outcomes in ILD research.

Frailty and geriatric conditions in older patients with idiopathic pulmonary fibrosis.

BACKGROUND: Functional status, an important predictor of health outcomes in older patients, has not been studied in an IPF population. This study aimed to determine the prevalence of frailty and geriatric conditions in older patients with IPF. METHODS: IPF patients age ≥65 years were identified prospectively at the University of Michigan. Frailty was assessed using the Fried frailty phenotype. Questionnaires addressing functional status, geriatric conditions and symptoms were administered. Quantitative measurement of pectoralis muscle area was performed. Patient variables were compared among different frailty groups. RESULTS: Of the 50 participants, 48% were found to be frail and 40% had ≥2 geriatric conditions. Frailty was associated with increased age, lower lung function, shorter 6-min walk distance, higher symptom scores and a greater number of comorbidities, geriatric conditions and functional limitations (p < 0.05). Pectoralis muscle area was nearly significant (p = 0.08). Self-reported fatigue score (odds ratio [OR] = 2.13, confidence interval [CI] 95% 1.23-3.70, p = 0.0068) and diffusion capacity (OR = 0.54 CI 95% 0.35-0.85, p = 0.0071) were independent predictors of frailty. CONCLUSIONS: Frailty and geriatric conditions are common in older patients with IPF. The presence of frailty was associated with objective (diffusion capacity) and subjective (self-reported fatigue score) data. Longitudinal evaluation is necessary to determine impact of frailty on disease-related outcomes in IPF.

Hypersensitivity Pneumonitis: Radiologic Phenotypes Are Associated With Distinct Survival Time and Pulmonary Function Trajectory.

BACKGROUND: Hypersensitivity pneumonitis (HP) is an interstitial lung disease with a better prognosis, on average, than idiopathic pulmonary fibrosis (IPF). We compare survival time and pulmonary function trajectory in patients with HP and IPF by radiologic phenotype. METHODS: HP (n = 117) was diagnosed if surgical/transbronchial lung biopsy, BAL, and exposure history results suggested this diagnosis. IPF (n = 152) was clinically and histopathologically diagnosed. All participants had a baseline high-resolution CT (HRCT) scan and FVC % predicted. Three thoracic radiologists documented radiologic features. Survival time is from HRCT scan to death or lung transplant. Cox proportional hazards models identify variables associated with survival time. Linear mixed models compare post-HRCT scan FVC % predicted trajectories. RESULTS: Subjects were grouped by clinical diagnosis and three mutually exclusive radiologic phenotypes: honeycomb present, non-honeycomb fibrosis (traction bronchiectasis and reticulation) present, and nonfibrotic. Nonfibrotic HP had the longest event-free median survival (> 14.73 years) and improving FVC % predicted (1.92%; 95% CI, 0.49-3.35; P = .009). HP with non-honeycomb fibrosis had longer survival than IPF (> 7.95 vs 5.20 years), and both groups experienced a significant decline in FVC % predicted. Subjects with HP and IPF with honeycombing had poor survival (2.76 and 2.81 years, respectively) and significant decline in FVC % predicted. CONCLUSIONS: Three prognostically distinct, radiologically defined phenotypes are identified among patients with HP. The importance of pursuing a specific diagnosis (eg, HP vs IPF) among patients with non-honeycomb fibrosis is highlighted. When radiologic honeycombing is present, invasive diagnostic testing directed at determining the diagnosis may be of limited value given a uniformly poor prognosis.

Development and validation of a radiological diagnosis model for hypersensitivity pneumonitis.

High-resolution computed tomography (HRCT) may be useful for diagnosing hypersensitivity pneumonitis. Here, we develop and validate a radiological diagnosis model and model-based points score.Patients with interstitial lung disease seen at the University of Michigan Health System (derivation cohort) or enrolling in the Lung Tissue Research Consortium (validation cohort) were included. A thin-section, inspiratory HRCT scan was required. Thoracic radiologists documented radiological features.The derivation cohort comprised 356 subjects (33.9% hypersensitivity pneumonitis) and the validation cohort comprised 424 subjects (15.5% hypersensitivity pneumonitis). An age-, sex- and smoking status-adjusted logistic regression model identified extent of mosaic attenuation or air trapping greater than that of reticulation ("MA-AT>Reticulation"; OR 6.20, 95% CI 3.53-10.90; p<0.0001) and diffuse axial disease distribution (OR 2.33, 95% CI 1.31-4.16; p=0.004) as hypersensitivity pneumonitis predictors (area under the receiver operating characteristic curve 0.814). A model-based score >2 (1 point for axial distribution, 2 points for "MA-AT>Reticulation") has specificity 90% and positive predictive value (PPV) 74% in the derivation cohort and specificity 96% and PPV 44% in the validation cohort. Similar model performance is seen with population restriction to those reporting no exposure (score >2: specificity 91%).When radiological mosaic attenuation or air trapping are more extensive than reticulation and disease has diffuse axial distribution, hypersensitivity pneumonitis specificity is high and false diagnosis risk low (<10%), but PPV is diminished in a low-prevalence setting.

Utility of Transbronchial vs Surgical Lung Biopsy in the Diagnosis of Suspected Fibrotic Interstitial Lung Disease.

BACKGROUND: Surgical lung biopsy (SLB) is invasive and not possible in all patients with undiagnosed interstitial lung disease (ILD). We hypothesized that transbronchial biopsy (TBB) findings combined with clinical and high-resolution CT (HRCT) data leads to a confident diagnosis congruent to SLB and therefore avoids the need for SLB in some patients. METHODS: We evaluated 33 patients being investigated for suspected ILD who underwent HRCT, TBB, and SLB. First, clinicians, radiologists, and a pathologist reviewed the clinical information and HRCT and TBB findings. Clinicians were asked to provide a diagnosis and were also asked if SLB was needed for a more confident diagnosis. Subsequently, the clinical, HRCT, and SLB data were reviewed, and the same participants were asked to provide a final diagnosis. Clinician consensus and overall agreement between TBB- and SLB-based diagnoses were calculated. RESULTS: Four patients had definite usual interstitial pneumonia (UIP) on HRCT and would not be considered for biopsy using current guidelines. Of the 29 patients without a definitive HRCT diagnosis, the clinicians felt confident of the diagnosis (ie, would not recommend SLB) in six cases. In these cases, there was 100% agreement between TBB and SLB diagnoses. UIP was the most common diagnosis (n = 3) and was associated with an HRCT diagnosis of possible UIP/nonspecific interstitial pneumonia-like. Agreement was poor (33%) between TBB and SLB diagnoses when confidence in the TBB diagnosis was low. CONCLUSIONS: Information from TBB, when combined with clinical and HRCT data, may provide enough information to make a confident and accurate diagnosis in approximately 20% to 30% of patients with ILD.