Factors Associated with Persistence of Severe Asthma from Late Adolescence to Early Adulthood.

RATIONALE: Asthma severity in children generally starts mild but may progress and stay severe for unknown reasons. OBJECTIVES: Identify factors in childhood that predict persistence of severe asthma in late adolescence and early adulthood. METHODS: The Childhood Asthma Management Program is the largest and longest asthma trial in 1041 children aged 5-12 years with mild to moderate asthma. We evaluated 682 participants from the program with analyzable data in late adolescence (age 17-19) and early adulthood (age 21-23). MEASUREMENTS: Severe asthma was defined using criteria from the American Thoracic Society and the National Asthma Education and Prevention Program to best capture severe asthma. Logistic regression with stepwise elimination was used to analyze clinical features, biomarkers, and lung function predictive of persistence of severe asthma. MAIN RESULTS: In late adolescence and early adulthood 12% and 19% of the patents had severe asthma, respectively; only 6% were severe at both time periods. For every 5% decrease in post bronchodilator FEV1/FVC in childhood, the odds of persistence of severe asthma increased 2.36-fold (95% CI: 1.70-3.28; p <0.0001), for participants with maternal smoking during pregnancy odds of persistence of severe asthma increased 3.17-fold (95% CI: 1.18-8.53, p=0.02). Reduced growth lung function trajectory was significantly associated with persistence of severe asthma compared to normal growth. CONCLUSIONS: Lung function and maternal smoking during pregnancy were significant predictors of severe asthma from late adolescence to early adulthood. Interventions to preserve lung function early may prevent disease progression.

MnTE-2-PyP disrupts Staphylococcus aureus biofilms in a novel fracture model.

Biofilm-associated infections in orthopedic surgery lead to worse clinical outcomes and greater morbidity and mortality. The scope of the problem encompasses infected total joints, internally fixed fractures, and implanted devices. Diagnosis is difficult. Cultures are often negative, and antibiotic treatments are ineffective. The infections resist killing by the immune system and antibiotics. The organized matrix structure of extracellular polymeric substances within the biofilm shields and protects the bacteria from identification and immune cell action. Bacteria in biofilms actively modulate their redox environment and can enhance the matrix structure by creating an oxidizing environment. We postulated that a potent redox-active metalloporphyrin MnTE-2-PyP (chemical name: manganese (II) meso-tetrakis-(N-methylpyridinium-2-yl) porphyrin) that scavenges reactive species and modulates the redox state to a reduced state, would improve the effect of antibiotic treatment for a biofilm-associated infection. An infected fracture model with a midshaft femoral osteotomy was created in C57B6 mice, internally fixed with an intramedullary 23-gauge needle and seeded with a biofilm-forming variant of Staphylococcus aureus. Animals were divided into three treatment groups: control, antibiotic alone, and combined antibioticplus MnTE-2-PyP. The combined treatment group had significantly decreased bacterial counts in harvested bone, compared with antibiotic alone. In vitro crystal violet assay of biofilm structure and corresponding nitroblue tetrazolium assay for reactive oxygen species (ROS) demonstrated that MnTE-2-PyP decreased the biofilm structure and reduced ROS in a correlated and dose-dependent manner. The biofilm structure is redox-sensitive in S. aureus and an ROS scavenger improved the effect of antibiotic therapy in model of biofilm-associated infections.

Localization of Macrophages in the Human Lung via Design-based Stereology.

Rationale: Interstitial macrophages (IMs) and airspace macrophages (AMs) play critical roles in lung homeostasis and host defense, and are central to the pathogenesis of a number of lung diseases. However, the absolute numbers of macrophages and the precise anatomic locations they occupy in the healthy human lung have not been quantified.Objectives: To determine the precise number and anatomic location of human pulmonary macrophages in nondiseased lungs and to quantify how this is altered in chronic cigarette smokers.Methods: Whole right upper lobes from 12 human donors without pulmonary disease (6 smokers and 6 nonsmokers) were evaluated using design-based stereology. CD206 (cluster of differentiation 206)-positive/CD43+ AMs and CD206+/CD43- IMs were counted in five distinct anatomical locations using the optical disector probe.Measurements and Main Results: An average of 2.1 × 109 IMs and 1.4 × 109 AMs were estimated per right upper lobe. Of the AMs, 95% were contained in diffusing airspaces and 5% in airways. Of the IMs, 78% were located within the alveolar septa, 14% around small vessels, and 7% around the airways. The local density of IMs was greater in the alveolar septa than in the connective tissue surrounding the airways or vessels. The total number and density of IMs was 36% to 56% greater in the lungs of cigarette smokers versus nonsmokers.Conclusions: The precise locations occupied by pulmonary macrophages were defined in nondiseased human lungs from smokers and nonsmokers. IM density was greatest in the alveolar septa. Lungs from chronic smokers had increased IM numbers and overall density, supporting a role for IMs in smoking-related disease.

COPDGene® 2019: Redefining the Diagnosis of Chronic Obstructive Pulmonary Disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) remains a major cause of morbidity and mortality. Present-day diagnostic criteria are largely based solely on spirometric criteria. Accumulating evidence has identified a substantial number of individuals without spirometric evidence of COPD who suffer from respiratory symptoms and/or increased morbidity and mortality. There is a clear need for an expanded definition of COPD that is linked to physiologic, structural (computed tomography [CT]) and clinical evidence of disease. Using data from the COPD Genetic Epidemiology study (COPDGene®), we hypothesized that an integrated approach that includes environmental exposure, clinical symptoms, chest CT imaging and spirometry better defines disease and captures the likelihood of progression of respiratory obstruction and mortality. METHODS: Four key disease characteristics - environmental exposure (cigarette smoking), clinical symptoms (dyspnea and/or chronic bronchitis), chest CT imaging abnormalities (emphysema, gas trapping and/or airway wall thickening), and abnormal spirometry - were evaluated in a group of 8784 current and former smokers who were participants in COPDGene® Phase 1. Using these 4 disease characteristics, 8 categories of participants were identified and evaluated for odds of spirometric disease progression (FEV1 > 350 ml loss over 5 years), and the hazard ratio for all-cause mortality was examined. RESULTS: Using smokers without symptoms, CT imaging abnormalities or airflow obstruction as the reference population, individuals were classified as Possible COPD, Probable COPD and Definite COPD. Current Global initiative for obstructive Lung Disease (GOLD) criteria would diagnose 4062 (46%) of the 8784 study participants with COPD. The proposed COPDGene® 2019 diagnostic criteria would add an additional 3144 participants. Under the new criteria, 82% of the 8784 study participants would be diagnosed with Possible, Probable or Definite COPD. These COPD groups showed increased risk of disease progression and mortality. Mortality increased in patients as the number of their COPD characteristics increased, with a maximum hazard ratio for all cause-mortality of 5.18 (95% confidence interval [CI]: 4.15-6.48) in those with all 4 disease characteristics. CONCLUSIONS: A substantial portion of smokers with respiratory symptoms and imaging abnormalities do not manifest spirometric obstruction as defined by population normals. These individuals are at significant risk of death and spirometric disease progression. We propose to redefine the diagnosis of COPD through an integrated approach using environmental exposure, clinical symptoms, CT imaging and spirometric criteria. These expanded criteria offer the potential to stimulate both current and future interventions that could slow or halt disease progression in patients before disability or irreversible lung structural changes develop.

Subtypes of COPD Have Unique Distributions and Differential Risk of Mortality.

BACKGROUND: Previous attempts to explore the heterogeneity of chronic obstructive pulmonary disease (COPD) clustered individual patients using clinical, demographic, and disease features. We developed continuous multidimensional disease axes based on radiographic and spirometric variables that split into an airway-predominant axis and an emphysema-predominant axis. METHODS: The COPD Genetic Epidemiology study (COPDGene®) is a cohort of current and former smokers, > 45 years, with at least 10 pack years of smoking history. Spirometry measures, blood pressure and body mass were directly measured. Mortality was assessed through continuing longitudinal follow-up and cause of death was adjudicated. Among 8157 COPDGene® participants with complete spirometry and computed tomography (CT) measures, the top 2 deciles of the airway-predominant and emphysema-predominant axes previously identified were used to categorize individuals into 3 groups having the highest risk for mortality using Cox proportional hazard ratios. These groups were also assessed for causal mortality. Biomarkers of COPD (fibrinogen, soluble receptor for advanced glycation end products [sRAGE], C-reactive protein [CRP], clara cell secretory protein [CC16], surfactant-D [SP-D]) were compared by group. FINDINGS: High-risk subtype classification was defined for 2638 COPDGene® participants who were in the highest 2 deciles of either the airway-predominant and/or emphysema-predominant axis (32% of the cohort). These high-risk participants fell into 3 groups: airway-predominant disease only (APD-only), emphysema-predominant disease only (EPD-only) and combined APD-EPD. There was 26% mortality for the APD-only group, 21% mortality for the EPD-only group, and 54% mortality for the combined APD-EPD group. The APD-only group (n=1007) was younger, had a lower forced expiratory volume in 1 second (FEV1) percent (%) predicted and a strong association with the preserved ratio-impaired spirometry (PRISm) quadrant. The EPD-only group (n=1006) showed a relatively higher FEV1 % predicted and included largely GOLD stage 0, 1 and 2 partipants. Individuals in each of the 3 high-risk groups were at greater risk for respiratory mortality, while those in the APD-only group were additionally at greater risk for cardiovascular mortality. Biomarker analysis demonstrated a significant association of the APD-only group with CRP, and sRAGE demonstrated greatest significance with both the EPD-only and the combined APD-EPD groups. INTERPRETATION: Among current and former smokers, individuals in the highest 2 deciles for mortality risk on the airway-predominant axis and the emphysema-predominant axis have unique associations to spirometric patterns, different imaging characteristics, biomarkers and causal mortality.

One-Year Outcomes Following Tracheostomy for Acute Respiratory Failure.

OBJECTIVES: Tracheostomy utilization has dramatically increased recently. Large gaps exist between expected and actual outcomes resulting in significant decisional conflict and regret. We determined 1-year patient outcomes and healthcare utilization following tracheostomy to aid in decision-making and resource allocation. DESIGN: Retrospective cohort study. SETTING: All California hospital discharges from 2012 to 2013 with follow-up through 2014. PATIENTS: Nonsurgical patients who received a tracheostomy for acute respiratory failure. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Our primary outcome was 30-day, 90-day, and 1-year mortality. We also determined hospitals readmissions rates and healthcare utilization in the first year following tracheostomy. We identified 8,343 tracheostomies during the study period. One-year mortality following tracheostomy was high, 46.5%. Older adults (≥ 65 yr) had significantly higher mortality compared with younger patients (< 65 yr) (54.7% vs 36.5%; p < 0.0001). Median survival for older adults was 175 days (95% CI, 150-202 d) compared with greater than 1 year for younger adults (adjusted hazard ratio, 1.25; 95% CI, 1.14-1.36). Within 1 year of tracheostomy, 60.3% of patients required hospital readmission. Older adults were more likely to be readmitted in the first year after tracheostomy compared with younger adults (66.1% vs 55.2%; adjusted hazard ratio, 1.19; 95% CI, 1.09-1.29). Total short-term acute care hospital costs (index and readmissions) in the first year after tracheostomy were high (mean, $215,369; SD, $160,874). CONCLUSIONS: Long-term outcomes following tracheostomy are extremely poor with high mortality, morbidity, and healthcare resource utilization especially among older patients. Some subsets of younger patients may have better outcomes compared with the general tracheostomy population. Short-term acute care costs were extremely high in the first year following tracheostomy. If extended to the entire U.S. population, total short-term acute care hospital costs approach $11 billion dollars per year for tracheostomy-related to acute respiratory failure. These findings may aid families and surrogates in the decision-making process.

Identifying Smoking-Related Disease on Lung Cancer Screening CT Scans: Increasing the Value.

BACKGROUND: Lung cancer screening (LCS) via chest computed tomography (CT) scans can save lives by identifying early-stage tumors. However, most smokers die of comorbid smoking-related diseases. LCS scans contain information about smoking-related conditions that is not currently systematically assessed. Identifying these common comorbid diseases on CT could increase the value of screening with minimal impact on LCS programs. We determined the prevalence of 3 comorbid diseases from LCS eligible scans and quantified related adverse outcomes. METHODS: We studied COPD Genetic Epidemiology study (COPDGene®) participants (n=4078) who met criteria for LCS screening at enrollment (age > 55 years, and < 80 years, > 30 pack years smoking, current smoker or former smoker within 15 years of smoking cessation). CT scans were assessed for coronary artery calcification (CAC), emphysema, and vertebral bone density. We tracked the following clinically significant events: myocardial infarctions (MIs), strokes, pneumonia, respiratory exacerbations, and hip and vertebral fractures. RESULTS: Overall, 77% of eligible CT scans had one or more of these diagnoses identified. CAC (> 100 mg) was identified in 51% of scans, emphysema in 44%, and osteoporosis in 54%. Adverse events related to the underlying smoking-related diseases were common, with 50% of participants reporting at least one. New diagnoses of cardiovascular disease, emphysema and osteoporosis were made in 25%, 7% and 46%, of participants respectively. New diagnosis of disease was associated with significantly more adverse events than in participants who did not have CT diagnoses for both osteoporosis and cardiovascular risk. CONCLUSIONS: Expanded analysis of LCS CT scans identified individuals with evidence of previously undiagnosed cardiovascular disease, emphysema or osteoporosis that corresponded with adverse events. LCS CT scans can potentially facilitate diagnoses of these smoking-related diseases and provide an opportunity for treatment or prevention.

Transitional human alveolar type II epithelial cells suppress extracellular matrix and growth factor gene expression in lung fibroblasts.

Epithelial-fibroblast interactions are thought to be very important in the adult lung in response to injury, but the specifics of these interactions are not well defined. We developed coculture systems to define the interactions of adult human alveolar epithelial cells with lung fibroblasts. Alveolar type II cells cultured on floating collagen gels reduced the expression of type 1 collagen (COL1A1) and α-smooth muscle actin (ACTA2) in fibroblasts. They also reduced fibroblast expression of hepatocyte growth factor (HGF), fibroblast growth factor 7 (FGF7, KGF), and FGF10. When type II cells were cultured at an air-liquid interface to maintain high levels of surfactant protein expression, this inhibitory activity was lost. When type II cells were cultured on collagen-coated tissue culture wells to reduce surfactant protein expression further and increase the expression of some type I cell markers, the epithelial cells suppressed transforming growth factor-ß (TGF-ß)-stimulated ACTA2 and connective tissue growth factor (CTGF) expression in lung fibroblasts. Our results suggest that transitional alveolar type II cells and likely type I cells but not fully differentiated type II cells inhibit matrix and growth factor expression in fibroblasts. These cells express markers of both type II cells and type I cells. This is probably a normal homeostatic mechanism to inhibit the fibrotic response in the resolution phase of wound healing. Defining how transitional type II cells convert activated fibroblasts into a quiescent state and inhibit the effects of TGF-ß may provide another approach to limiting the development of fibrosis after alveolar injury.

Identification of Nonaggressive Pulmonary Nodules Using an Optimized Scoring System.

PURPOSE: The purpose of this study was to define the optimal scoring method for identifying benign intrapulmonary lymph nodes. MATERIALS AND METHODS: Subjects for this study were selected from the COPDGene study, a large multicenter longitudinal observational cohort study. A retrospective case-control analysis was performed using identified nodules on a subset of 377 patients who demonstrated 765 pulmonary nodules on their baseline computed tomography (CT) study. Nodule characteristics of 636 benign nodules (which resolved or showed <20% growth rate at 5 y follow-up) were compared with 51 nodules that occurred in the same lobe as a reported malignancy. Two radiologists scored each pulmonary nodule on the basis of intrapulmonary lymph node characteristics. A simple scoring strategy weighing all characteristics equally was compared with an optimized scoring strategy that weighed characteristics on the basis of their relative importance in identifying benign pulmonary nodules. RESULTS: A total of 479 of 636 benign pulmonary nodules had the majority of lymph node characteristics, whereas only 1 subpleural nodule with the majority of lymph node characteristics appeared to be malignant. Only 279 of 479 (58%) of benign pulmonary nodules with the majority of lymph node characteristics were intrafissural or subpleural. The optimized scoring strategy showed improved performance compared with the simple scoring strategy with average area under the curve of 0.80 versus 0.55. Optimized cutoff scores showed negative likelihood values for both readers of <0.2. A simulation showed a potential reduction in CT utilization of up to 36% for Fleischner criteria and up to 5% for LUNG-RADS. CONCLUSIONS: Nodules with the majority of lymph node characteristics, regardless of location, are likely benign, and weighing certain lymph node characteristics greater than others can improve overall performance. Given the potential to reduce CT utilization, lymph node characteristics should be considered when recommending appropriate follow-up.

TGF beta inhibits HGF, FGF7, and FGF10 expression in normal and IPF lung fibroblasts.

TGF beta is a multifunctional cytokine that is important in the pathogenesis of pulmonary fibrosis. The ability of TGF beta to stimulate smooth muscle actin and extracellular matrix gene expression in fibroblasts is well established. In this report, we evaluated the effect of TGF beta on the expression of HGF, FGF7 (KGF), and FGF10, important growth and survival factors for the alveolar epithelium. These growth factors are important for maintaining type II cells and for restoration of the epithelium after lung injury. Under conditions of normal serum supplementation or serum withdrawal TGF beta inhibited fibroblast expression of HGF, FGF7, and FGF10. We confirmed these observations with genome wide RNA sequencing of the response of control and IPF fibroblasts to TGF beta. In general, gene expression in IPF fibroblasts was similar to control fibroblasts. Reduced expression of HGF, FGF7, and FGF10 is another means whereby TGF beta impairs epithelial healing and promotes fibrosis after lung injury.

CT-based Visual Classification of Emphysema: Association with Mortality in the COPDGene Study.

Purpose To determine whether visually assessed patterns of emphysema at CT might provide a simple assessment of mortality risk among cigarette smokers. Materials and Methods Of the first 4000 cigarette smokers consecutively enrolled between 2007 and 2011 in this COPDGene study, 3171 had data available for both visual emphysema CT scores and survival. Each CT scan was retrospectively visually scored by two analysts using the Fleischner Society classification system. Severity of emphysema was also evaluated quantitatively by using percentage lung volume occupied by low-attenuation areas (voxels with attenuation of -950 HU or less) (LAA-950). Median duration of follow-up was 7.4 years. Regression analysis for the relationship between imaging patterns and survival was based on the Cox proportional hazards model, with adjustment for age, race, sex, height, weight, pack-years of cigarette smoking, current smoking status, educational level, LAA-950, and (in a second model) forced expiratory volume in 1 second (FEV1). Results Observer agreement in visual scoring was good (weighted κ values, 0.71-0.80). There were 519 deaths in the study cohort. Compared with subjects who did not have visible emphysema, mortality was greater in those with any grade of emphysema beyond trace (adjusted hazard ratios, 1.7, 2.5, 5.0, and 4.1, respectively, for mild centrilobular emphysema, moderate centrilobular emphysema, confluent emphysema, and advanced destructive emphysema, P < .001). This increased mortality generally persisted after adjusting for LAA-950. Conclusion The visual presence and severity of emphysema is associated with significantly increased mortality risk, independent of the quantitative severity of emphysema. Online supplemental material is available for this article.

Protein Tyrosine Phosphatase-N13 Promotes Myofibroblast Resistance to Apoptosis in Idiopathic Pulmonary Fibrosis.

RATIONALE: Idiopathic pulmonary fibrosis (IPF) is a progressive, fibrotic interstitial lung disease characterized by (myo)fibroblast accumulation and collagen deposition. Resistance to Fas-induced apoptosis is thought to facilitate (myo)fibroblast persistence in fibrotic lung tissues by poorly understood mechanisms. OBJECTIVES: To test the hypothesis that PTPN13 (protein tyrosine phosphatase-N13) is expressed by IPF lung (myo)fibroblasts, promotes their resistance to Fas-induced apoptosis, and contributes to the development of pulmonary fibrosis. METHODS: PTPN13 was localized in lung tissues from patients with IPF and control subjects by immunohistochemical staining. Inhibition of PTPN13 function in primary IPF and normal lung (myo)fibroblasts was accomplished by: 1) downregulation with TNF-α (tumor necrosis factor-α)/IFN-γ, 2) siRNA knockdown, or 3) a cell-permeable Fas/PTPN13 interaction inhibitory peptide. The role of PTPN13 in the development of pulmonary fibrosis was assessed in mice with genetic deficiency of PTP-BL, the murine ortholog of PTPN13. MEASUREMENTS AND MAIN RESULTS: PTPN13 was constitutively expressed by (myo)fibroblasts in the fibroblastic foci of patients with IPF. Human lung (myo)fibroblasts, which are resistant to Fas-induced apoptosis, basally expressed PTPN13 in vitro. TNF-α/IFN-γ or siRNA-mediated PTPN13 downregulation and peptide-mediated inhibition of the Fas/PTPN13 interaction in human lung (myo)fibroblasts promoted Fas-induced apoptosis. Bleomycin-challenged PTP-BL-/- mice, while developing inflammatory lung injury, exhibited reduced pulmonary fibrosis compared with wild-type mice. CONCLUSIONS: These findings suggest that PTPN13 mediates the resistance of human lung (myo)fibroblasts to Fas-induced apoptosis and promotes pulmonary fibrosis in mice. Our results suggest that strategies aimed at interfering with PTPN13 expression or function may represent a novel strategy to reduce fibrosis in IPF.

Alpha-1 Antitrypsin PiMZ Genotype Is Associated with Chronic Obstructive Pulmonary Disease in Two Racial Groups.

RATIONALE: Alpha-1 antitrypsin deficiency, caused primarily by homozygosity for the Z allele of the SERPINA1 gene, is a well-established genetic cause of chronic obstructive pulmonary disease (COPD). Whether the heterozygous PiMZ genotype for alpha-1 antitrypsin confers increased risk for COPD has been debated. OBJECTIVES: We analyzed 8,271 subjects in the Genetic Epidemiology of COPD (COPDGene) Study, hypothesizing that PiMZ would independently associate with COPD and COPD-related phenotypes. METHODS: The COPDGene Study comprises a multiethnic, cross-sectional, observational cohort of non-Hispanic white and African American current and former smokers with at least 10 pack-years of smoking who were enrolled for detailed clinical and genetic studies of COPD and COPD-related traits. We performed multivariate logistic regression analysis for moderate to severe COPD and assessed Pi genotype with other relevant covariates in models stratified by race. We analyzed quantitative characteristics on the basis of volumetric computed tomography with generalized linear models controlling for genotype, scanner type, and similar covariates. RESULTS: White PiMZ COPDGene subjects had significantly lower lung function, FEV1 percent predicted (68 ± 28 vs. 75 ± 27; P = 0.0005), and FEV1/FVC ratio (0.59 ± 0.18 vs. 0.63 ± 0.17; P = 0.0008), as well as more radiographic emphysema (P = 0.001), than subjects without alpha-1 antitrypsin Z risk alleles. Similarly, African American PiMZ subjects had lower lung function, FEV1 percent predicted (65 ± 33 vs. 84 ± 25; P = 0.009) and FEV1/FVC (0.61 ± 0.21 vs. 0.71 ± 0.15; P = 0.03). CONCLUSIONS: In the COPDGene Study, we demonstrate that PiMZ heterozygous individuals who smoke are at increased risk for COPD and obstructive lung function impairment compared with Z-allele noncarriers, regardless of race. Although severe alpha-1 antitrypsin deficiency is uncommon in African Americans, our study adds further support for initial targeted detection of all subjects with COPD for alpha-1 antitrypsin deficiency, including African Americans. Clinical trial registered with www.clinicaltrials.gov (NCT00608784).

Clinical Predictors of a Diagnosis of Common Variable Immunodeficiency-related Granulomatous-Lymphocytic Interstitial Lung Disease.

RATIONALE: Granulomatous-lymphocytic interstitial lung disease (GLILD) has emerged as a major cause of morbidity in patients with common variable immunodeficiency (CVID). While GLILD is among the most serious noninfectious pulmonary complications of CVID, risk factors for this condition have not been reported. OBJECTIVES: To identify clinical, physiologic, and serologic risk factors for GLILD in adults with CVID. METHODS: Of 345 consecutive adult patients with CVID, we identified 34 in the National Jewish Health research database who had a radiographic-pathologic diagnosis of GLILD evaluated between 2002 and 2014. Each case was age and sex matched to 52 CVID control subjects. We used logistic regression to determine independent predictors of GLILD. A mixed effects model was used to estimate the longitudinal change in percent predicted FVC. MEASUREMENTS AND MAIN RESULTS: The mean time from CVID diagnosis to GLILD detection was 7.8 years. Compared with matched control subjects, cases were more likely to have a history of autoimmune cytopenia, hypersplenism, polyarthritis, lower marginal zone and switched memory B cells, and restrictive lung function. Multivariate analysis revealed that hypersplenism (odds ratio [OR], 24; 95% confidence interval [CI], 4.5-179.1), polyarthritis (OR, 19; 95% CI, 2.3-206.8), and percent predicted FVC (OR, 0.93; 95% CI, 0.87-0.98) were independently associated with the development of GLILD. The rate of change of percent predicted FVC (slope, P = 0.48) did not vary significantly in patients with GLILD over a mean follow-up of 7 years after diagnosis. CONCLUSIONS: Hypersplenism and polyarthritis are strong risk factors for GLILD in patients with CVID. Percent predicted FVC remained stable over time in patients with GLILD.

Association Between Expiratory Central Airway Collapse and Respiratory Outcomes Among Smokers.

IMPORTANCE: Central airway collapse greater than 50% of luminal area during exhalation (expiratory central airway collapse [ECAC]) is associated with cigarette smoking and chronic obstructive pulmonary disease (COPD). However, its prevalence and clinical significance are unknown. OBJECTIVE: To determine whether ECAC is associated with respiratory morbidity in smokers independent of underlying lung disease. DESIGN, SETTING, AND PARTICIPANTS: Analysis of paired inspiratory-expiratory computed tomography images from a large multicenter study (COPDGene) of current and former smokers from 21 clinical centers across the United States. Participants were enrolled from January 2008 to June 2011 and followed up longitudinally until October 2014. Images were initially screened using a quantitative method to detect at least a 30% reduction in minor axis tracheal diameter from inspiration to end-expiration. From this sample of screen-positive scans, cross-sectional area of the trachea was measured manually at 3 predetermined levels (aortic arch, carina, and bronchus intermedius) to confirm ECAC (>50% reduction in cross-sectional area). EXPOSURES: Expiratory central airway collapse. MAIN OUTCOMES AND MEASURES: The primary outcome was baseline respiratory quality of life (St George's Respiratory Questionnaire [SGRQ] scale 0 to 100; 100 represents worst health status; minimum clinically important difference [MCID], 4 units). Secondary outcomes were baseline measures of dyspnea (modified Medical Research Council [mMRC] scale 0 to 4; 4 represents worse dyspnea; MCID, 0.7 units), baseline 6-minute walk distance (MCID, 30 m), and exacerbation frequency (events per 100 person-years) on longitudinal follow-up. RESULTS: The study included 8820 participants with and without COPD (mean age, 59.7 [SD, 6.9] years; 4667 [56.7%] men; 4559 [51.7%] active smokers). The prevalence of ECAC was 5% (443 cases). Patients with ECAC compared with those without ECAC had worse SGRQ scores (30.9 vs 26.5 units; P < .001; absolute difference, 4.4 [95% CI, 2.2-6.6]) and mMRC scale scores (median, 2 [interquartile range [IQR], 0-3]) vs 1 [IQR, 0-3]; P < .001]), but no significant difference in 6-minute walk distance (399 vs 417 m; absolute difference, 18 m [95% CI, 6-30]; P = .30), after adjustment for age, sex, race, body mass index, forced expiratory volume in the first second, pack-years of smoking, and emphysema. On follow-up (median, 4.3 [IQR, 3.2-4.9] years), participants with ECAC had increased frequency of total exacerbations (58 vs 35 events per 100 person-years; incidence rate ratio [IRR], 1.49 [95% CI, 1.29-1.72]; P < .001) and severe exacerbations requiring hospitalization (17 vs 10 events per 100 person-years; IRR, 1.83 [95% CI, 1.51-2.21]; P < .001). CONCLUSIONS AND RELEVANCE: In a cross-sectional analysis of current and former smokers, the presence of ECAC was associated with worse respiratory quality of life. Further studies are needed to assess long-term associations with clinical outcomes.

Identifying a Deletion Affecting Total Lung Capacity Among Subjects in the COPDGene Study Cohort.

Chronic obstructive pulmonary disease (COPD) is a progressive disease with both environmental and genetic risk factors. Genome-wide association studies (GWAS) have identified multiple genomic regions influencing risk of COPD. To thoroughly investigate the genetic etiology of COPD, however, it is also important to explore the role of copy number variants (CNVs) because the presence of structural variants can alter gene expression and can be causal for some diseases. Here, we investigated effects of polymorphic CNVs on quantitative measures of pulmonary function and chest computed tomography (CT) phenotypes among subjects enrolled in COPDGene, a multisite study. COPDGene subjects consist of roughly one-third African American (AA) and two-thirds non-Hispanic white adult smokers (with or without COPD). We estimated CNVs using PennCNV on 9,076 COPDGene subjects using Illumina's Omni-Express genome-wide marker array. We tested for association between polymorphic CNV components (defined as disjoint intervals of copy number regions) for several quantitative phenotypes associated with COPD within each racial group. Among the AAs, we identified a polymorphic CNV on chromosome 5q35.2 located between two genes (FAM153B and SIMK1, but also harboring several pseudo-genes) giving genome-wide significance in tests of association with total lung capacity (TLCCT ) as measured by chest CT scans. This is the first study of genome-wide association tests of polymorphic CNVs and TLCCT . Although the ARIC cohort did not have the phenotype of TLCCT , we found similar counts of CNV deletions and amplifications among AA and European subjects in this second cohort.

Clinical and Radiologic Disease in Smokers With Normal Spirometry.

IMPORTANCE: Airflow obstruction on spirometry is universally used to define chronic obstructive pulmonary disease (COPD), and current or former smokers without airflow obstruction may assume that they are disease free. OBJECTIVE: To identify clinical and radiologic evidence of smoking-related disease in a cohort of current and former smokers who did not meet spirometric criteria for COPD, for whom we adopted the discarded label of Global Initiative for Obstructive Lung Disease (GOLD) 0. DESIGN, SETTING, AND PARTICIPANTS: Individuals from the Genetic Epidemiology of COPD (COPDGene) cross-sectional observational study completed spirometry, chest computed tomography (CT) scans, a 6-minute walk, and questionnaires. Participants were recruited from local communities at 21 sites across the United States. The GOLD 0 group (n = 4388) (ratio of forced expiratory volume in the first second of expiration [FEV1] to forced vital capacity >0.7 and FEV1 ≥80% predicted) from the COPDGene study was compared with a GOLD 1 group (n = 794), COPD groups (n = 3690), and a group of never smokers (n = 108). Recruitment began in January 2008 and ended in July 2011. MAIN OUTCOMES AND MEASURES: Physical function impairments, respiratory symptoms, CT abnormalities, use of respiratory medications, and reduced respiratory-specific quality of life. RESULTS: One or more respiratory-related impairments were found in 54.1% (2375 of 4388) of the GOLD 0 group. The GOLD 0 group had worse quality of life (mean [SD] St George's Respiratory Questionnaire total score, 17.0 [18.0] vs 3.8 [6.8] for the never smokers; P < .001) and a lower 6-minute walk distance, and 42.3% (127 of 300) of the GOLD 0 group had CT evidence of emphysema or airway thickening. The FEV1 percent predicted distribution and mean for the GOLD 0 group were lower but still within the normal range for the population. Current smoking was associated with more respiratory symptoms, but former smokers had greater emphysema and gas trapping. Advancing age was associated with smoking cessation and with more CT findings of disease. Individuals with respiratory impairments were more likely to use respiratory medications, and the use of these medications was associated with worse disease. CONCLUSIONS AND RELEVANCE: Lung disease and impairments were common in smokers without spirometric COPD. Based on these results, we project that there are 35 million current and former smokers older than 55 years in the United States who may have unrecognized disease or impairment. The effect of chronic smoking on the lungs and the individual is substantially underestimated when using spirometry alone.

Visual Assessment of CT Findings in Smokers With Nonobstructed Spirometric Abnormalities in The COPDGene® Study.

Within the COPD Genetic Epidemiology (COPDGene®) study population of cigarette smokers, 9% were found to be unclassifiable by the Global Initiative for chronic Obstructive Lung Disease (GOLD) criteria. This study was to identify the differences in computed tomography (CT) findings between this nonobstructed (GOLDU) group and a control group of smokers with normal lung function. This research was approved by the institutional review board of each institution. CT images of 400 participants in the COPDGene® study (200 GOLDU, 200 smokers with normal lung function) were retrospectively evaluated in a blinded fashion. Visual CT assessment included lobar analysis of emphysema (type, extent), presence of paraseptal emphysema, airway wall thickening, expiratory air trapping, centrilobular nodules, atelectasis, non-fibrotic and fibrotic interstitial lung disease (ILD), pleural thickening, diaphragmatic eventration, vertebral body changes and internal thoracic diameters (in mm). Univariate comparisons of groups for each CT parameter and multiple logistic regression were performed to determine the imaging features associated with GOLDU. When compared with the control group, GOLDU participants had a significantly higher prevalence of unilateral diaphragm eventration (30% vs. 16%), airway wall thickening, centrilobular nodules, reticular abnormality, paraseptal emphysema (33% vs. 17%), linear atelectasis (60% vs. 35.6%), kyphosis (12% vs. 4%), and a smaller internal transverse thoracic diameter (255 ± 22.5 [standard deviation] vs. 264.8 ± 22.4, mm) (all p<0.05). With multiple logistic regression, all of these CT parameters, except non-fibrotic ILD and kyphosis, remained significantly associated with GOLDU status (p<0.05). In cigarette smokers, chest wall abnormalities and parenchymal lung disease, which contribute to restrictive physiologic impairment, are associated with GOLD-nonobstructed status.

Comparison of radiographic and clinical characteristics of low-risk and high-risk cystic fibrosis genotypes.

BACKGROUND: Patients with cystic fibrosis (CF) exhibit a wide range of disease severity, and can be broadly stratified into high-risk and low-risk groups based on cystic fibrosis transmembrane conductance regulator (CFTR) mutation class. Patients with a low-risk genotype are often diagnosed as adults, with milder disease and lower sweat chloride values. The aim of the current study was to better understand radiographic and clinical characteristics of sinus disease in adult CF patients within this risk category. METHODS: Adult CF patients were retrospectively compared to a control group of patients with chronic rhinosinusitis. CF diagnostic testing and pulmonary characteristics were compared between high-risk and low-risk CF groups, and sinus CT findings were compared among all 3 groups. RESULTS: When comparing CF cohorts (n = 25 and 30, respectively), earlier age at diagnosis (p < 0.001), higher sweat chloride values (p < 0.001), lower forced expiratory volume in 1 second (FEV1 ) values (p < 0.001), and a higher prevalence of pulmonary infection with Pseudomonas aeruginosa (p = 0.001) were found in the high-risk genotype group. A significantly increased incidence of sinus hypoplasia/aplasia and bony sclerosis was seen when comparing both CF groups to the control cohort (n = 30), as well as when comparing the high-risk and low-risk CF genotype cohorts. CONCLUSION: The current study describes clinicopathologic findings of sinus disease in adult CF patients in the context of genotype severity. Our data demonstrate that while patients within a low-risk genotype cohort have generally milder lung disease, they retain classic radiographic findings of CF sinus disease that can help raise the index of suspicion for undiagnosed CF.

Epidemiology, genetics, and subtyping of preserved ratio impaired spirometry (PRISm) in COPDGene.

BACKGROUND: Preserved Ratio Impaired Spirometry (PRISm), defined as a reduced FEV1 in the setting of a preserved FEV1/FVC ratio, is highly prevalent and is associated with increased respiratory symptoms, systemic inflammation, and mortality. Studies investigating quantitative chest tomographic features, genetic associations, and subtypes in PRISm subjects have not been reported. METHODS: Data from current and former smokers enrolled in COPDGene (n = 10,192), an observational, cross-sectional study which recruited subjects aged 45-80 with ≥10 pack years of smoking, were analyzed. To identify epidemiological and radiographic predictors of PRISm, we performed univariate and multivariate analyses comparing PRISm subjects both to control subjects with normal spirometry and to subjects with COPD. To investigate common genetic predictors of PRISm, we performed a genome-wide association study (GWAS). To explore potential subgroups within PRISm, we performed unsupervised k-means clustering. RESULTS: The prevalence of PRISm in COPDGene is 12.3%. Increased dyspnea, reduced 6-minute walk distance, increased percent emphysema and decreased total lung capacity, as well as increased segmental bronchial wall area percentage were significant predictors (p-value <0.05) of PRISm status when compared to control subjects in multivariate models. Although no common genetic variants were identified on GWAS testing, a significant association with Klinefelter's syndrome (47XXY) was observed (p-value < 0.001). Subgroups identified through k-means clustering include a putative "COPD-subtype", "Restrictive-subtype", and a highly symptomatic "Metabolic-subtype". CONCLUSIONS: PRISm subjects are clinically and genetically heterogeneous. Future investigations into the pathophysiological mechanisms behind and potential treatment options for subgroups within PRISm are warranted. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT000608764.