Asthma morbidity measures across Black ethnic subgroups

BACKGROUND

Black adults are disproportionately affected by asthma and are often considered a homogeneous group in research studies despite cultural and ancestral differences.

OBJECTIVE

We sought to determine if asthma morbidity differs across adults in Black ethnic subgroups.

METHODS

Adults with moderate-severe asthma were recruited across the continental United States and Puerto Rico for the PREPARE (PeRson EmPowered Asthma RElief) trial. Using self-identifications, we categorized multiethnic Black (ME/B) participants (n = 226) as Black Latinx participants (n = 146) or Caribbean, continental African, or other Black participants (n = 80). African American (AA/B) participants (n = 518) were categorized as Black participants who identified their ethnicity as being American. Baseline characteristics and retrospective asthma morbidity measures (self-reported exacerbations requiring systemic corticosteroids [SCs], emergency department/urgent care [ED/UC] visits, hospitalizations) were compared across subgroups using multivariable regression.

RESULTS

Compared with AA/B participants, ME/B participants were more likely to be younger, residing in the US Northeast, and Spanish speaking and to have lower body mass index, health literacy, and <1 comorbidity, but higher blood eosinophil counts. In a multivariable analysis, ME/B participants were significantly more likely to have ED/UC visits (incidence rate ratio [IRR] = 1.34, 95% CI = 1.04-1.72) and SC use (IRR = 1.27, 95% CI = 1.00-1.62) for asthma than AA/B participants. Of the ME/B subgroups, Puerto Rican Black Latinx participants (n = 120) were significantly more likely to have ED/UC visits (IRR = 1.64, 95% CI = 1.22-2.21) and SC use for asthma (IRR = 1.43, 95% CI = 1.06-1.92) than AA/B participants. There were no significant differences in hospitalizations for asthma among subgroups.

CONCLUSIONS

ME/B adults, specifically Puerto Rican Black Latinx adults, have higher risk of ED/UC visits and SC use for asthma than other Black subgroups.

Preference for and impact of telehealth vs in-person asthma visits among Black and Latinx adults

BACKGROUND

Black and Latinx adults experience disproportionate asthma-related morbidity and limited specialty care access. The severe acute respiratory syndrome coronavirus 2 pandemic expanded telehealth use.

OBJECTIVE

To evaluate visit type (telehealth [TH] vs in-person [IP]) preferences and the impact of visit type on asthma outcomes among Black and Latinx adults with moderate-to-severe asthma.

METHODS

For this PREPARE trial ancillary study, visit type preference was surveyed by e-mail or telephone post-trial. Emergency medical record data on visit types and asthma outcomes were available for a subset (March 2020 to April 2021). Characteristics associated with visit type preferences, and relationships between visit type and asthma outcomes (control [Asthma Control Test] and asthma-related quality of life [Asthma Symptom Utility Index]), were tested using multivariable regression.

RESULTS

A total of 866 participants consented to be surveyed, with 847 respondents. Among the participants with asthma care experience with both visit types, 42.0% preferred TH for regular checkups, which associated with employment (odds ratio [OR] = 1.61; 95% confidence interval [CI], 1.09-2.39; P = .02), lower asthma medication adherence (OR = 1.06; 95% CI, 1.01-1.11; P = .03), and having more historical emergency department and urgent care asthma visits (OR = 1.10 for each additional visit; 95% CI, 1.02-1.18; P = .02), after adjustment. Emergency medical record data were available for 98 participants (62 TH, 36 IP). Those with TH visits were more likely Latinx, from the Southwest, employed, using inhaled corticosteroid-only controller therapy, with lower body mass index, and lower self-reported asthma medication adherence vs those with IP visits only. Both groups had comparable Asthma Control Test (18.4 vs 18.9, P = .52) and Asthma Symptom Utility Index (0.79 vs 0.84, P = .16) scores after adjustment.

CONCLUSION

TH may be similarly efficacious as and often preferred over IP among Black and Latinx adults with moderate-to-severe asthma, especially for regular checkups.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02995733.

Interstitial lung abnormalities in a large clinical lung cancer screening cohort: association with mortality and ILD diagnosis

BACKGROUND

Interstitial lung abnormalities (ILA) are CT findings suggestive of interstitial lung disease in individuals without a prior diagnosis or suspicion of ILD. Previous studies have demonstrated that ILA are associated with clinically significant outcomes including mortality. The aim of this study was to determine the prevalence of ILA in a large CT lung cancer screening program and the association with clinically significant outcomes including mortality, hospitalizations, cancer and ILD diagnosis.

METHODS

This was a retrospective study of individuals enrolled in a CT lung cancer screening program from 2012 to 2014. Baseline and longitudinal CT scans were scored for ILA per Fleischner Society guidelines. The primary analyses examined the association between baseline ILA and mortality, all-cause hospitalization, and incidence of lung cancer. Kaplan-Meier plots were generated to visualize the associations between ILA and lung cancer and all-cause mortality. Cox regression proportional hazards models were used to test for this association in both univariate and multivariable models.

RESULTS

1699 subjects met inclusion criteria. 41 (2.4%) had ILA and 101 (5.9%) had indeterminate ILA on baseline CTs. ILD was diagnosed in 10 (24.4%) of 41 with ILA on baseline CT with a mean time from baseline CT to diagnosis of 4.47 ± 2.72 years. On multivariable modeling, the presence of ILA remained a significant predictor of death, HR 3.87 (2.07, 7.21; p < 0.001) when adjusted for age, sex, BMI, pack years and active smoking, but not of lung cancer and all-cause hospital admission. Approximately 50% with baseline ILA had progression on the longitudinal scan.

CONCLUSIONS

ILA identified on baseline lung cancer screening exams are associated with all-cause mortality. In addition, a significant proportion of patients with ILA are subsequently diagnosed with ILD and have CT progression on longitudinal scans.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov; No.: NCT04503044.

Reliever-Triggered Inhaled Glucocorticoid in Black and Latinx Adults with Asthma

BACKGROUND

Black and Latinx patients bear a disproportionate burden of asthma. Efforts to reduce the disproportionate morbidity have been mostly unsuccessful, and guideline recommendations have not been based on studies in these populations.

METHODS

In this pragmatic, open-label trial, we randomly assigned Black and Latinx adults with moderate-to-severe asthma to use a patient-activated, reliever-triggered inhaled glucocorticoid strategy (beclomethasone dipropionate, 80 μg) plus usual care (intervention) or to continue usual care. Participants had one instructional visit followed by 15 monthly questionnaires. The primary end point was the annualized rate of severe asthma exacerbations. Secondary end points included monthly asthma control as measured with the Asthma Control Test (ACT; range, 5 [poor] to 25 [complete control]), quality of life as measured with the Asthma Symptom Utility Index (ASUI; range, 0 to 1, with lower scores indicating greater impairment), and participant-reported missed days of work, school, or usual activities. Safety was also assessed.

RESULTS

Of 1201 adults (603 Black and 598 Latinx), 600 were assigned to the intervention group and 601 to the usual-care group. The annualized rate of severe asthma exacerbations was 0.69 (95% confidence interval [CI], 0.61 to 0.78) in the intervention group and 0.82 (95% CI, 0.73 to 0.92) in the usual-care group (hazard ratio, 0.85; 95% CI, 0.72 to 0.999; P = 0.048). ACT scores increased by 3.4 points (95% CI, 3.1 to 3.6) in the intervention group and by 2.5 points (95% CI, 2.3 to 2.8) in the usual-care group (difference, 0.9; 95% CI, 0.5 to 1.2); ASUI scores increased by 0.12 points (95% CI, 0.11 to 0.13) and 0.08 points (95% CI, 0.07 to 0.09), respectively (difference, 0.04; 95% CI, 0.02 to 0.05). The annualized rate of missed days was 13.4 in the intervention group and 16.8 in the usual-care group (rate ratio, 0.80; 95% CI, 0.67 to 0.95). Serious adverse events occurred in 12.2% of the participants, with an even distribution between the groups.

CONCLUSIONS

Among Black and Latinx adults with moderate-to-severe asthma, provision of an inhaled glucocorticoid and one-time instruction on its use, added to usual care, led to a lower rate of severe asthma exacerbations. (Funded by the Patient-Centered Outcomes Research Institute and others; PREPARE ClinicalTrials.gov number, NCT02995733.).

Qualitative coronary artery calcification scores and risk of all cause, COPD and pneumonia hospital admission in a large CT lung cancer screening cohort

BACKGROUND

Patients at high-risk for lung cancer and qualified for CT lung cancer screening (CTLS) are at risk for numerous cardio-pulmonary comorbidities. We sought to examine if qualitatively assessed coronary artery calcifications (CAC) on CTLS exams could identify patients at increased risk for non-cardiovascular events such as all cause, COPD and pneumonia related hospitalization and to verify previously reported associations between CAC and mortality and cardiovascular events.

STUDY DESIGN AND METHODS

Patients (n = 4673) from Lahey Hospital and Medical Center who underwent CTLS from January 12, 2012 through September 30, 2017 were included with clinical follow-up through September 30, 2019. CTLS exams were qualitatively scored for the presence and severity of CAC at the time of exam interpretation using a four point scale: none, mild, moderate, and marked. Multivariable Cox regression models were used to evaluate the association between CT qualitative CAC and all-cause, COPD-related, and pneumonia-related hospital admissions.

RESULTS

3631 (78%) of individuals undergoing CTLS had some degree of CAC on their baseline exam: 1308 (28.0%), 1128 (24.1%), and 1195 (25.6%) had mild, moderate and marked coronary calcification, respectively. Marked CAC was associated with all-cause hospital admission and pneumonia related admissions HR 1.48; 95% CI 1.23-1.78 and HR 2.19; 95% 1.30-3.71, respectively. Mild, moderate and marked CAC were associated with COPD-related admission HR 2.30; 95% CI 1.31-4.03, HR 2.17; 95% CI 1.20-3.91 and HR 2.27; 95% CI 1.24-4.15.

CONCLUSION

Qualitative CAC on CTLS exams identifies individuals at elevated risk for all cause, pneumonia and COPD-related hospital admissions.

A randomized, open-label, pragmatic study to assess reliever-triggered inhaled corticosteroid in African American/Black and Hispanic/Latinx adults with asthma: Design and methods of the PREPARE trial

BACKGROUND

Asthma prevalence, morbidity, and mortality disproportionately impact African American/Black (AA/B) and Hispanic/Latinx (H/L) communities. Adherence to daily inhaled corticosteroid (ICS), recommended by asthma guidelines in all but the mildest cases of asthma, is generally poor. As-needed ICS has shown promise as a patient-empowering asthma management strategy, but it has not been rigorously studied in AA/B or H/L patients or in a real-world setting. Design and Aim The PeRson EmPowered Asthma RElief (PREPARE) Study is a randomized, open-label, pragmatic study which aims to assess whether a patient-guided, reliever-triggered ICS strategy called PARTICS (Patient-Activated Reliever-Triggered Inhaled CorticoSteroid) can improve asthma outcomes in AA/B and H/L adult patient populations. In designing and implementing the study, the PREPARE research team has relied heavily on advice from AA/B and H/L Patient Partners and other stakeholders. Methods PREPARE is enrolling 1200 adult participants (600 AA/Bs, 600H/Ls) with asthma. Participants are randomized to PARTICS + Usual Care (intervention) versus Usual Care (control). Following a single in-person enrollment visit, participants complete monthly questionnaires for 15 months. The primary endpoint is annualized asthma exacerbation rate. Secondary endpoints include asthma control; preference-based quality of life; and days lost from work, school, or usual activities. Discussion The PREPARE study features a pragmatic design allowing for the real-world assessment of a patient-centered, reliever-triggered ICS strategy in AA/B and H/L patients. Outcomes of this study have the potential to offer powerful evidence supporting PARTICS as an effective asthma management strategy in patient populations that suffer disproportionately from asthma morbidity and mortality.

Rapid Intensive Care Unit Onboarding in Response to a Pandemic

BACKGROUND

In the wake of the coronavirus disease 2019 (COVID-19) pandemic, hospital resources have been stretched to their limits. We introduced an innovative course to rapidly on-board a group of non-intensive care unit (ICU) nurse practitioners as they begin to practice working in a critical care setting.

OBJECTIVE

To assess whether a brief educational course could improve non-ICU practitioners' knowledge and comfort in practicing in an intensive care setting.

METHODS

We implemented a multi-strategy blended 12-week curriculum composed of bedside teaching, asynchronous online learning and simulation. The course content was a product of data collected from a targeted needs assessment. The cognitive learning objectives were taught through the online modules. Four simulation sessions were used to teach procedural skills. Bedside teaching simultaneously occurred from critical care faculty during daily rounds. We assessed learning through a pre and post knowledge multiple choice question (MCQ) test. Faculty assessed learners by direct observation and review of clinical documentation. We evaluated learner reaction and comfort in critical practice by comparing pre and post surveys.

RESULTS

All 7 NPs were satisfied with the course and found the format to work well with their clinical schedules. The course also improved their self-reported comfort in managing critically ill patients in a medical ICU. There was an increase in the mean group score from the pre-to the post-course MCQ (60% vs 73%).

CONCLUSIONS

The COVID-19 Critical Care Course (CCCC) for NPs was implemented in our ICU to better prepare for an anticipated second surge. It focused on delivering practical knowledge and skills as learners cared for critically ill COVID-19 patients. In a short period of time, it engaged participants in active learning and allowed them to feel more confident in applying their education.

ADAM15 expression is increased in lung CD8+ T cells, macrophages, and bronchial epithelial cells in patients with COPD and is inversely related to airflow obstruction

BACKGROUND

A disintegrin and metalloproteinase domain-15 (ADAM15) is expressed by activated leukocytes, and fibroblasts in vitro. Whether ADAM15 expression is increased in the lungs of COPD patients is not known.

METHODS

ADAM15 gene expression and/or protein levels were measured in whole lung and bronchoalveolar lavage (BAL) macrophage samples obtained from COPD patients, smokers, and non-smokers. Soluble ADAM15 protein levels were measured in BAL fluid (BALF) and plasma samples from COPD patients and controls. Cells expressing ADAM15 in the lungs were identified using immunostaining. Staining for ADAM15 in different cells in the lungs was related to forced expiratory volume in 1 s (FEV1), ratio of FEV1 to forced vital capacity (FEV1/FVC), and pack-years of smoking history.

RESULTS

ADAM15 gene expression and/or protein levels were increased in alveolar macrophages and whole lung samples from COPD patients versus smokers and non-smokers. Soluble ADAM15 protein levels were similar in BALF and plasma samples from COPD patients and controls. ADAM15 immunostaining was increased in macrophages, CD8+ T cells, epithelial cells, and airway α-smooth muscle (α-SMA)-positive cells in the lungs of COPD patients. ADAM15 immunostaining in macrophages, CD8+ T cells and bronchial (but not alveolar) epithelial cells was related inversely to FEV1 and FEV1/FVC, but not to pack-years of smoking history. ADAM15 staining levels in airway α-SMA-positive cells was directly related to FEV1/FVC. Over-expressing ADAM15 in THP-1 cells reduced their release of matrix metalloproteinases and CCL2.

CONCLUSIONS

These results link increased ADAM15 expression especially in lung leukocytes and bronchial epithelial cells to the pathogenesis of COPD.

"You Leave There Feeling Part of Something": A Qualitative Study of Hospitalized COPD Patients' Perceptions of Pulmonary Rehabilitation

Rationale

Current guidelines recommend that patients hospitalized for acute exacerbations of chronic obstructive pulmonary disease (COPD) initiate pulmonary rehabilitation (PR) shortly after discharge from the hospital. However, fewer than 2 percent of Medicare beneficiaries do so. Few studies have examined hospitalized patients’ perceptions of the barriers and facilitators to enroll in PR. The aim of this study was to develop an understanding of these factors by interviewing patients.

Methods

We conducted semi-structured interviews with patients during a hospitalization for COPD exacerbation in a large teaching hospital. Directed content analysis was used to code and analyze interview transcripts.

Results

Of the 15 patients we interviewed, 9 had participated in PR prior to their hospitalization, 10 were women; 4 were black, and 1 was Hispanic. Facilitators of enrollment included a desire to learn more about the disease, social support, and trust in the health-care provider recommending PR. Barriers to enrollment included lack of awareness, family obligations, lack of motivation, and transportation. For those who had previous experience with PR, but who did not complete the program, another barrier was not feeling well enough. Facilitators to adherence included the educational component of the program; feeling better through exercise; and a social connection with both participants and staff. For some patients. PR contributed to a renewed sense of hope or meaning. Most interviewees expressed interest in a peer coaching program.

Conclusion

Our results highlight the importance of increasing awareness of PR and building trust between the provider and patients to facilitate initial enrollment. Future interventions to improve enrollment and adherence should address the need for education about the benefits of PR and the value of social support.

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Genetic Switches between Cancer and Emphysema Resolution of Cigarette-Smoke Induced Inflammation

Cigarette smoke initiates an inflammatory response that has aftermath long after quitting. We segregated former smokers, according to their lung function and their co-founding diseases, in 3 groups: Cancer, Emphysema and COPD. Then we searched for outlier genes in intersections of Venn diagrams where we identified 6 subsets and 23 genes that may be responsible for disease outcome. Genes expressed in the cancer patients with or without emphysema (PPA subset) were BHLH, FPRL2, CD49D, DEADH, NRs4A3, MBLL, GNS, BE675435, ISGF-3, and FLJ23462. Patients with emphysema as co-founding disease, with or without cancer (APP), had only ANXA2 in common. Genes expressed only in non-cancer patients (AAP subset) of COPD group were IL-1A, SOX13, RPP38; TBXA2R, NPEPL1, CFLAR, TFEB, PRKCBP1, IGF1R, DDX11, and KCNAB1. HIV-1Rev was the gene expressed in cancer patients with emphysema (APA subset). Then, we also looked at out-layers genes significantly expressed in all patients (PPP subset with 5066 genes), the down-regulated in Emphysema were MMP9, PLUNC, CEACAM5, and NR4A1 while the up-regulated were F2R, COL15A1, PDE4C, and BGN. We chose genes and checked them at the protein level on immune cells, this showed that neutrophils from Cancer group had increased expression of CD49d, and their total number was also increased in bronchial-alveolar lavage (154%). Macrophages in the lung of patients with emphysema were associated with a significant increase of adhesion molecule CD58 and to significant CD95 decrease, indicating they do not die. Besides, macrophages downregulated MMP9 in the lung compared to blood macrophages. Overall, we find that cancer progression requires a stickier and greater number of neutrophils in the lung while emphysema requires stickier and longevous macrophages to lead matrix destruction, and together with higher expression of SOX13 and RPP38, may promote autoimmunity. We also identified two genes, ANXA2 and HIV1-rev, that may be a pivot between cancer and emphysema outcome of inflammation.

Plasma metabolomics and clinical predictors of survival differences in COPD patients

BACKGROUND

Plasma metabolomics profile (PMP) in COPD has been associated with clinical characteristics, but PMP's relationship to survival has not been reported. We determined PMP differences between patients with COPD who died an average of 2 years after enrollment (Non-survivors, NS) compared to those who survived (S) and also with age matched controls (C).

METHODS

We studied prospectively 90 patients with severe COPD and 30 controls. NS were divided in discovery and validation cohorts (30 patients each) and the results compared to the PMP of 30 S and C. All participants completed lung function tests, dyspnea scores, quality of life, exercise capacity, BODE index, and plasma metabolomics by liquid and gas chromatography / mass spectometry (LC/MS, LC/MS2, GC/MS). Statistically, we used Random Forest Analysis (RFA) and Support Vector Machine (SVM) to determine metabolites that differentiated the 3 groups and compared the ability of metabolites vs. clinical characteristics to classify patients into survivors and non-survivors.

RESULTS

There were 79 metabolites statistically different between S and NS [p < 0.05 and false discovery rate (q value) < 0.1]. RFA and SVM classification of COPD survivors and non-survivors had a predicted accuracy of 74 and 85% respectively. Elevation of tricyclic acid cycle intermediates branched amino acids depletion and increase in lactate, fructose and xylonate showed the most relevant differences between S vs. NS suggesting alteration in mitochondrial oxidative energy generation. PMP had similar predictive power for risk of death as information provided by clinical characteristics.

CONCLUSIONS

A plasma metabolomic profile characterized by an oxidative energy production difference between survivors and non-survivors was observed in COPD patients 2 years before death.

A Disintegrin and Metalloproteinase Domain-8: A Novel Protective Proteinase in Chronic Obstructive Pulmonary Disease

RATIONALE

ADAM8 (a disintegrin and metalloproteinase domain-8) is expressed by leukocytes and epithelial cells in health, but its contribution to the pathogenesis of chronic obstructive pulmonary disease (COPD) is unknown.

OBJECTIVES

To determine whether the expression of ADAM8 is increased in the lungs of patients with COPD and cigarette smoke (CS)-exposed mice, and whether ADAM8 promotes the development of COPD.

METHODS

ADAM8 levels were measured in lung, sputum, plasma, and/or BAL fluid samples from patients with COPD, smokers, and nonsmokers, and wild-type (WT) mice exposed to CS versus air. COPD-like lung pathologies were compared in CS-exposed WT versus Adam8-/- mice.

MEASUREMENTS AND MAIN RESULTS

ADAM8 immunostaining was reduced in macrophages, and alveolar and bronchial epithelial cells in the lungs of patients with COPD versus control subjects, and CS- versus air-exposed WT mice. ADAM8 levels were similar in plasma, sputum, and BAL fluid samples from patients with COPD and control subjects. CS-exposed Adam8-/- mice had greater airspace enlargement and airway mucus cell metaplasia than WT mice, but similar small airway fibrosis. CS-exposed Adam8-/- mice had higher lung macrophage counts, oxidative stress levels, and alveolar septal cell death rates, but lower alveolar septal cell proliferation rates and soluble epidermal growth factor receptor BAL fluid levels than WT mice. Adam8 deficiency increased lung inflammation by reducing CS-induced activation of the intrinsic apoptosis pathway in macrophages. Human ADAM8 proteolytically shed the epidermal growth factor receptor from bronchial epithelial cells to reduce mucin expression in vitro. Adam8 bone marrow chimera studies revealed that Adam8 deficiency in leukocytes and lung parenchymal cells contributed to the exaggerated COPD-like disease in Adam8-/- mice.

CONCLUSIONS

Adam8 deficiency increases CS-induced lung inflammation, emphysema, and airway mucus cell metaplasia. Strategies that increase or prolong ADAM8's expression in the lung may have therapeutic efficacy in COPD.

Results of a Patient Survey Regarding COPD Knowledge, Treatment Experiences, and Practices With Inhalation Devices

BACKGROUND

Successful inhalation therapy depends on the ability of patients with COPD to properly use devices. We explored subjects' COPD knowledge, including education they receive from health care providers, treatment experiences, and practices with inhalation devices.

METHODS

A multiple-choice online survey, developed by a steering committee of American Thoracic Society clinicians and scientists, was administered to subjects with COPD who were sourced from the Harris Poll Online panel.

RESULTS

Of the 254 respondents (mean age 61.8 y; 49% males), most subjects (82%) claimed to understand their disease and available treatments, yet COPD symptoms and causes were well known to only 45% and 44% of subjects, respectively. Forty-three percent of subjects had ever used a pressurized metered-dose inhaler or dry-powder inhaler. Of the 54% of subjects who had ever used a small-volume nebulizer (SVN), 63% considered this device to be easy to use, 55% considered it to be fast-acting, 53% considered it to be convenient, and 38% considered it to be essential for treatment. Among subjects who had ever used them, SVNs were preferred by 54% over other devices. One third of subjects desired more extensive education during office visits; 25% felt the time was insufficient to cover questions, and 15% felt their concerns about COPD treatment(s) were ignored. Subjects believed physicians (32%), nurses (26%), and no single provider (28%) were primarily responsible for training and assessing proper inhalation technique.

CONCLUSION

The survey showed differences between patients' beliefs and knowledge of COPD; the need for continuous education from health care providers, particularly on inhalation devices; and extensive use of pressurized metered-dose inhalers and dry-powder inhalers despite positive perceptions of SVNs.

Human Lung DNA Methylation Quantitative Trait Loci Colocalize with Chronic Obstructive Pulmonary Disease Genome-Wide Association Loci

RATIONALE

As the third leading cause of death in the United States, the impact of chronic obstructive pulmonary disease (COPD) makes identification of its molecular mechanisms of great importance. Genome-wide association studies (GWASs) have identified multiple genomic regions associated with COPD. However, genetic variation only explains a small fraction of the susceptibility to COPD, and sub-genome-wide significant loci may play a role in pathogenesis.

OBJECTIVES

Regulatory annotation with epigenetic evidence may give priority for further investigation, particularly for GWAS associations in noncoding regions. We performed integrative genomics analyses using DNA methylation profiling and genome-wide SNP genotyping from lung tissue samples from 90 subjects with COPD and 36 control subjects.

METHODS

We performed methylation quantitative trait loci (mQTL) analyses, testing for SNPs associated with percent DNA methylation and assessed the colocalization of these results with previous COPD GWAS findings using Bayesian methods in the R package coloc to highlight potential regulatory features of the loci.

MEASUREMENTS AND MAIN RESULTS

We identified 942,068 unique SNPs and 33,996 unique CpG sites among the significant (5% false discovery rate) cis-mQTL results. The genome-wide significant and subthreshold (P < 10-4) GWAS SNPs were enriched in the significant mQTL SNPs (hypergeometric test P < 0.00001). We observed enrichment for sites located in CpG shores and shelves, but not CpG islands. Using Bayesian colocalization, we identified loci in regions near KCNK3, EEFSEC, PIK3CD, DCDC2C, TCERG1L, FRMD4B, and IL27.

CONCLUSIONS

Colocalization of mQTL and GWAS loci provides regulatory characterization of significant and subthreshold GWAS findings, supporting a role for genetic control of methylation in COPD pathogenesis.

Results of a Pulmonologist Survey Regarding Knowledge and Practices With Inhalation Devices for COPD

BACKGROUND

COPD guidelines advise on inhaled medication use, yet no advice is offered on when to use and which type of patient could benefit from a specific delivery device. We investigated pulmonologists' perception of their knowledge and practices with delivery devices for COPD management.

METHODS

An online survey was designed by a steering committee of American Thoracic Society clinicians and scientists and conducted by a national market research firm between January 7 and 29, 2016.

RESULTS

Two hundred and five respondents completed the survey. Nearly 80% of the respondents believed that they were very knowledgeable in COPD management and the use of medications; 68% believed that they were knowledgeable about preventing exacerbations. Ninety-eight percent of the respondents stated that they were at least somewhat knowledgeable about devices. Many respondents (70%) stated that small-volume nebulizers were more effective than dry powder inhalers and pressurized metered-dose inhalers in the management of COPD exacerbations, and 63% believed that these were more effective in severe COPD (modified Medical Research Council dyspnea scale grade 4). Only 54% of the respondents discussed device options with their patients. Physician screening for physical or cognitive impairments that could impact device choices was 53% and 16%, respectively. Seventy percent of the respondents discussed device use, whereas 9% discussed cleaning and storage during a patient's first visit. Few respondents were very knowledgeable in teaching patients how to use devices (43%) and, specifically, how to use (32%) or clean and/or maintain (20%) small-volume nebulizers.

CONCLUSIONS

Most respondents were confident in their knowledge about treating COPD. Fewer respondents were confident about the use and maintenance of inhalation devices, and most respondents desired to learn more about inhalation devices.

Emphysema and extrapulmonary tissue loss in COPD: a multi-organ loss of tissue phenotype

We tested whether emphysema progression accompanies enhanced tissue loss in other body compartments in 1817 patients from the ECLIPSE chronic obstructive pulmonary disease (COPD) cohort.Clinical and selected systemic biomarker measurements were compared in subjects grouped by quantitative tomography scan emphysema quartiles using the percentage of low attenuation area (LAA%). Lowest and highest quartile patients had amino-acid metabolomic profiles. We related LAA% to 3 years decline in lung function (forced expiratory volume in 1 s (FEV₁)), body mass index (BMI), fat-free mass index (FFMI) and exacerbations, hospitalisations and mortality rates.Participants with more baseline emphysema had lower FEV₁, BMI and FFMI, worse functional capacity, and less cardiovascular disease but more osteoporosis. Systemic C-reactive protein and interleukin-6 levels were similar among groups, but club cell protein 16 was higher and interleukin-8, surfactant protein D and soluble receptor for advanced glycation end product were lower with more emphysema. Metabolomics differed between extreme emphysema quartiles. Patients with more emphysema had accelerated FEV₁, BMI and FFMI decline and more exacerbations, hospitalisations and mortality.COPD patients with more emphysema undergo excessive loss of pulmonary and extrapulmonary tissue, which is probably related to abnormal tissue maintenance. Because of worse clinical outcomes, we propose this subgroup be named the multi-organ loss of tissue (MOLT) COPD phenotype.

Prevalence of persistent blood eosinophilia: relation to outcomes in patients with COPD

The impact of blood eosinophilia in chronic obstructive pulmonary disease (COPD) remains controversial.

To evaluate the prevalence and stability of a high level of blood eosinophils (≥300 cells·μL–1) and its relationship to outcomes, we determined blood eosinophils at baseline and over 2 years in 424 COPD patients (forced expiratory volume in 1 s (FEV1) 60% predicted) and 67 smokers without COPD from the CHAIN cohort, and in 308 COPD patients (FEV1 60% predicted) in the BODE cohort. We related eosinophil levels to exacerbations and survival using Cox hazard analysis.

In COPD patients, 15.8% in the CHAIN cohort and 12.3% in the BODE cohort had persistently elevated blood eosinophils at all three visits. A significant proportion (43.8%) of patients had counts that oscillated above and below the cut-off points, while the rest had persistent eosinophil levels <300 cells·μL–1. A similar eosinophil blood pattern was observed in controls. Exacerbation rates did not differ in patients with and without eosinophilia. All-cause mortality was lower in patients with high eosinophils compared with those with values <300 cells·μL–1 (15.8% versus 33.7%; p=0.026).

In patients with COPD, blood eosinophils ≥300 cells·μL–1 persisting over 2 years was not a risk factor for COPD exacerbations. High eosinophil count was associated with better survival.

Chronic Obstructive Pulmonary Disease in Elderly Patients

Chronic obstructive pulmonary disease (COPD) is prevalent in the elderly population, with high impact on quality of life, morbidity, and mortality. The diagnosis is usually made based on symptoms and spirometry values that support the presence of airflow obstruction. However, the condition is frequently underdiagnosed. COPD is associated with premature aging and several other medical conditions that can partially explain its underdiagnosis and management. There are several pharmacologic and nonpharmacologic interventions proven to be effective in ameliorating the symptoms of COPD. Appropriate drug delivery and reduction of side effects is also pivotal in the management of patients with COPD.

A Pilot Study Linking Endothelial Injury in Lungs and Kidneys in Chronic Obstructive Pulmonary Disease

RATIONALE

Patients with chronic obstructive pulmonary disease (COPD) frequently have albuminuria (indicative of renal endothelial cell injury) associated with hypoxemia.

OBJECTIVES

To determine whether (1) cigarette smoke (CS)-induced pulmonary and renal endothelial cell injury explains the association between albuminuria and COPD, (2) CS-induced albuminuria is linked to increases in the oxidative stress-advanced glycation end products (AGEs) receptor for AGEs (RAGE) pathway, and (3) enalapril (which has antioxidant properties) limits the progression of pulmonary and renal injury by reducing activation of the AGEs-RAGE pathway in endothelial cells in both organs.

METHODS

In 26 patients with COPD, 24 ever-smokers without COPD, 32 nonsmokers who underwent a renal biopsy or nephrectomy, and in CS-exposed mice, we assessed pathologic and ultrastructural renal lesions, and measured urinary albumin/creatinine ratios, tissue oxidative stress levels, and AGEs and RAGE levels in pulmonary and renal endothelial cells. The efficacy of enalapril on pulmonary and renal lesions was assessed in CS-exposed mice.

MEASUREMENTS AND MAIN RESULTS

Patients with COPD and/or CS-exposed mice had chronic renal injury, increased urinary albumin/creatinine ratios, and increased tissue oxidative stress and AGEs-RAGE levels in pulmonary and renal endothelial cells. Treating mice with enalapril attenuated CS-induced increases in urinary albumin/creatinine ratios, tissue oxidative stress levels, endothelial cell AGEs and RAGE levels, pulmonary and renal cell apoptosis, and the progression of chronic renal and pulmonary lesions.

CONCLUSIONS

Patients with COPD and/or CS-exposed mice have pulmonary and renal endothelial cell injury linked to increased endothelial cell AGEs and RAGE levels. Albuminuria could identify patients with COPD in whom angiotensin-converting enzyme inhibitor therapy improves renal and lung function by reducing endothelial injury.

Functional interactors of three genome-wide association study genes are differentially expressed in severe chronic obstructive pulmonary disease lung tissue

In comparison to genome-wide association studies (GWAS), there has been poor replication of gene expression studies in chronic obstructive pulmonary disease (COPD). We performed microarray gene expression profiling on a large sample of resected lung tissues from subjects with severe COPD. Comparing 111 COPD cases and 40 control smokers, 204 genes were differentially expressed; none were at significant GWAS loci. The top differentially expressed gene was HMGB1, which interacts with AGER, a known COPD GWAS gene. Differentially expressed genes showed enrichment for putative interactors of the first three identified COPD GWAS genes IREB2, HHIP, and FAM13A, based on gene sets derived from protein and RNA binding studies, RNA-interference, a murine smoking model, and expression quantitative trait locus analyses. The gene module most highly associated for COPD in Weighted Gene Co-Expression Network Analysis (WGCNA) was enriched for B cell pathways, and shared seventeen genes with a mouse smoking model and twenty genes with previous emphysema studies. As in other common diseases, genes at COPD GWAS loci were not differentially expressed; however, using a combination of network methods, experimental studies and careful phenotype definition, we found differential expression of putative interactors of these genes, and we replicated previous human and mouse microarray results.

DNA methylation profiling in human lung tissue identifies genes associated with COPD

Chronic obstructive pulmonary disease (COPD) is a smoking-related disease characterized by genetic and phenotypic heterogeneity. Although association studies have identified multiple genomic regions with replicated associations to COPD, genetic variation only partially explains the susceptibility to lung disease, and suggests the relevance of epigenetic investigations. We performed genome-wide DNA methylation profiling in homogenized lung tissue samples from 46 control subjects with normal lung function and 114 subjects with COPD, all former smokers. The differentially methylated loci were integrated with previous genome-wide association study results. The top 535 differentially methylated sites, filtered for a minimum mean methylation difference of 5% between cases and controls, were enriched for CpG shelves and shores. Pathway analysis revealed enrichment for transcription factors. The top differentially methylated sites from the intersection with previous GWAS were in CHRM1, GLT1D1, and C10orf11; sorted by GWAS P-value, the top sites included FRMD4A, THSD4, and C10orf11. Epigenetic association studies complement genetic association studies to identify genes potentially involved in COPD pathogenesis. Enrichment for genes implicated in asthma and lung function and for transcription factors suggests the potential pathogenic relevance of genes identified through differential methylation and the intersection with a broader range of GWAS associations.

Increased expression of A Proliferation-Inducing Ligand (APRIL) in lung leukocytes and alveolar epithelial cells in COPD patients with non small cell lung cancer: a possible link between COPD and lung cancer?

Background: Chronic Obstructive Pulmonary Disease (COPD) is characterized by an excessive activation of the adaptive immune system and, in particular, uncontrolled expansion of the B-cell pool. One of the key promoters of B cell expansion is A PRoliferation-Inducing Ligand (APRIL). APRIL has been strongly linked to non small cell lung cancer (NSCLC) onset and progression previously. However, little is known about the expression of APRIL in the lungs of COPD patients. Methods: Using immuno-fluorescence staining, the expression of APRIL was assessed in sections of lungs from 4 subjects with primary diagnosis of COPD (FEV1 33 ± 20 % predicted), 4 subjects with primary diagnosis of NSCLC, 4 subjects diagnosed with both COPD and NSCLC, smokers without COPD or NSCLC and 3 healthy never-smokers. The percentage of B cells, alveolar macrophages (AMs) and polymorphonuclear neutrophils (PMNs) in the lung and alveolar epithelial cells (AECs) that stained positively for APRIL was quantified using epi-fluorescence microscopy and image analysis software. Results: The percentage of APRIL-expressing B cells, AMs, PMNs and alveolar epithelial cells (AECs) was higher in patients having both COPD and NSCLC than in patients with either COPD or NSCLC alone, SC or NSC (p < 0.03 for all comparisons). The percentage of APRIL-expressing AMs and AECs (but not in B cells) was higher in patients with NSCLC alone than in patients with COPD alone. The percentage of APRIL-expressing AECs (but not B cells or AMs) was higher in COPD patients than in SC and NSC (p < 0.05 for all comparisons). The percentage of APRIL-expressing B cells, AMs and AECs cells was similar in NSC and SC. Conclusion: The percentage of APRIL-expressing B cells, AMs and AECs is higher in the lungs of patients with both COPD and NSCLC than in patients with COPD or NSCLC alone or control subjects. These findings suggest that APRIL may contribute to the pathogenesis of both COPD and NSCLC, and possibly to the development of NSCLC in patients with established COPD.

Increased expression of A Proliferation-inducing Ligand (APRIL) in lung leukocytes and alveolar epithelial cells in COPD patients with non small cell lung cancer: a possible link between COPD and lung cancer?

Background

Chronic Obstructive Pulmonary Disease (COPD) is characterized by an excessive activation of the adaptive immune system and, in particular, uncontrolled expansion of the B-cell pool. One of the key promoters of B cell expansion is A PRoliferation-Inducing Ligand (APRIL). APRIL has been strongly linked to non small cell lung cancer (NSCLC) onset and progression previously. However, little is known about the expression of APRIL in the lungs of COPD patients.

Methods

Using immuno-fluorescence staining, the expression of APRIL was assessed in sections of lungs from 4 subjects with primary diagnosis of COPD (FEV₁ 33 ± 20 % predicted), 4 subjects with primary diagnosis of NSCLC, 4 subjects diagnosed with both COPD and NSCLC, smokers without COPD or NSCLC and 3 healthy never-smokers. The percentage of B cells, alveolar macrophages (AMs) and polymorphonuclear neutrophils (PMNs) in the lung and alveolar epithelial cells (AECs) that stained positively for APRIL was quantified using epi-fluorescence microscopy and image analysis software.

Results

The percentage of APRIL-expressing B cells, AMs, PMNs and alveolar epithelial cells (AECs) was higher in patients having both COPD and NSCLC than in patients with either COPD or NSCLC alone, SC or NSC (p < 0.03 for all comparisons). The percentage of APRIL-expressing AMs and AECs (but not in B cells) was higher in patients with NSCLC alone than in patients with COPD alone. The percentage of APRIL-expressing AECs (but not B cells or AMs) was higher in COPD patients than in SC and NSC (p < 0.05 for all comparisons). The percentage of APRIL-expressing B cells, AMs and AECs cells was similar in NSC and SC.

Conclusion

The percentage of APRIL-expressing B cells, AMs and AECs is higher in the lungs of patients with both COPD and NSCLC than in patients with COPD or NSCLC alone or control subjects. These findings suggest that APRIL may contribute to the pathogenesis of both COPD and NSCLC, and possibly to the development of NSCLC in patients with established COPD.

B Cell-Activating Factor. An Orchestrator of Lymphoid Follicles in Severe Chronic Obstructive Pulmonary Disease

RATIONALE

Patients with chronic obstructive pulmonary disease (COPD) have increased pulmonary lymphoid follicle (LF) counts. B cell-activating factor of tumor necrosis factor family (BAFF) regulates B cells in health, but its role in COPD pathogenesis is unclear.

OBJECTIVES

To determine whether BAFF expression in pulmonary LFs correlates with COPD severity, LF size or number, and/or readouts of B-cell function in LFs.

METHODS

We correlated BAFF immunostaining in LFs in lung explants or biopsies from nonsmoking control subjects (NSC), smokers without COPD (SC), and patients with COPD with the number and size of LFs, and LF B-cell apoptosis, activation, and proliferation. We analyzed serum BAFF levels and BAFF expression in B cells in blood and bronchoalveolar lavage samples from the same subject groups. We assessed whether: (1) cigarette smoke extract (CSE) increases B-cell BAFF expression and (2) recombinant BAFF (rBAFF) rescues B cells from CSE-induced apoptosis by inhibiting activation of nuclear factor-κB (NF-κB).

MEASUREMENTS AND MAIN RESULTS

Patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage IV COPD had increased numbers and larger pulmonary LFs than patients with GOLD stages I-II COPD and SC. We identified two main types of pulmonary LFs: (1) type A, the predominant type in GOLD stages I-II COPD and SC, characterized by abundant apoptotic but few BAFF-positive cells (mostly B cells); and (2) type B, the main type in GOLD stage IV COPD, characterized by abundant BAFF-positive cells but few apoptotic cells (mostly B cells). BAFF levels were also higher in blood and bronchoalveolar lavage B cells in patients with COPD versus NSC and SC. Surprisingly, rBAFF blocked CSE-induced B-cell apoptosis by inhibiting CSE-induced NF-κB activation.

CONCLUSIONS

Our data support the hypothesis that B-cell BAFF expression creates a self-perpetuating loop contributing to COPD progression by promoting pulmonary B-cell survival and LF expansion.

Lung-Function Trajectories Leading to Chronic Obstructive Pulmonary Disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is thought to result from an accelerated decline in forced expiratory volume in 1 second (FEV1) over time. Yet it is possible that a normal decline in FEV1 could also lead to COPD in persons whose maximally attained FEV1 is less than population norms.

METHODS

We stratified participants in three independent cohorts (the Framingham Offspring Cohort, the Copenhagen City Heart Study, and the Lovelace Smokers Cohort) according to lung function (FEV1 ≥80% or <80% of the predicted value) at cohort inception (mean age of patients, approximately 40 years) and the presence or absence of COPD at the last study visit. We then determined the rate of decline in FEV1 over time among the participants according to their FEV1 at cohort inception and COPD status at study end.

RESULTS

Among 657 persons who had an FEV1 of less than 80% of the predicted value before 40 years of age, 174 (26%) had COPD after 22 years of observation, whereas among 2207 persons who had a baseline FEV1 of at least 80% of the predicted value before 40 years of age, 158 (7%) had COPD after 22 years of observation (P<0.001). Approximately half the 332 persons with COPD at the end of the observation period had had a normal FEV1 before 40 years of age and had a rapid decline in FEV1 thereafter, with a mean (±SD) decline of 53±21 ml per year. The remaining half had had a low FEV1 in early adulthood and a subsequent mean decline in FEV1 of 27±18 ml per year (P<0.001), despite similar smoking exposure.

CONCLUSIONS

Our study suggests that low FEV1 in early adulthood is important in the genesis of COPD and that accelerated decline in FEV1 is not an obligate feature of COPD. (Funded by an unrestricted grant from GlaxoSmithKline and others.).

Protective role for club cell secretory protein-16 (CC16) in the development of COPD

Club cell secretory protein-16 (CC16) is the major secreted product of airway club cells, but its role in the pathogenesis of chronic obstructive pulmonary disease (COPD) is unclear. We measured CC16 airway expression in humans with and without COPD and CC16 function in a cigarette smoke (CS)-induced COPD murine model. Airway CC16 expression was measured in COPD patients, smokers without COPD and non-smokers. We exposed wildtype (WT) and CC16(-/-)mice to CS or air for up to 6 months, and measured airway CC16 expression, pulmonary inflammation, alveolar septal cell apoptosis, airspace enlargement, airway mucin 5AC (MUC5AC) expression, small airway remodelling and pulmonary function. Smokers and COPD patients had reduced airway CC16 immunostaining that decreased with increasing COPD severity. Exposing mice to CS reduced airway CC16 expression. CC16(-/-) mice had greater CS-induced emphysema, airway remodelling, pulmonary inflammation, alveolar cell apoptosis, airway MUC5AC expression, and more compliant lungs than WT mice. These changes were associated with increased nuclear factor-κB (NF-κB) activation in CC16(-/-) lungs. CS-induced acute pulmonary changes were reversed by adenoviral-mediated over-expression of CC16. CC16 protects lungs from CS-induced injury by reducing lung NF-κB activation. CS-induced airway CC16 deficiency increases CS-induced pulmonary inflammation and injury and likely contributes to the pathogenesis of COPD.

Emphysema and DLCO predict a clinically important difference for 6MWD decline in COPD

BACKGROUND

Exercise impairment is a central feature of chronic obstructive pulmonary disease (COPD), and a minimal clinically important difference (MCID) for 6-min walk distance (6MWD) decline (>30 m) has been associated with increased mortality. The predictors of the MCID are not fully known. We hypothesize that physiological factors and radiographic measures predict the MCID.

METHODS

We assessed 121 COPD subjects during 2 years using clinical variables, computed tomographic (CT) measures of emphysema, and functional measures including diffusion lung capacity for carbon monoxide (DLCO). The association between an MCID for 6MWD and clinical, CT, and physiologic predictors was assessed using logistic analysis. The C-statistic was used to assess the predictive ability of the models.

RESULTS

Forty seven (39%) subjects had an MCID. In an imaging-based model, log emphysema and age were the best predictors of MCID (emphysema Odds Ratio [OR] 2.47 95%CI [1.28-4.76]). In a physiologic model, DLCO, age, and male gender were selected the best predictors (DLCO OR 1.19 [1.08-1.31]). The C-statistic for the ability of these models to predict an MCID was 0.71 and 0.75, respectively.

CONCLUSION

In COPD patients the burden of emphysema on CT scan and DLCO predict a clinically meaningful decline in exercise capacity.

A novel nonhuman primate model of cigarette smoke-induced airway disease

Small animal models of chronic obstructive pulmonary disease (COPD) have several limitations for identifying new therapeutic targets and biomarkers for human COPD. These include a pulmonary anatomy that differs from humans, the limited airway pathologies and lymphoid aggregates that develop in smoke-exposed mice, and the challenges associated with serial biological sampling. Thus, we assessed the utility of cigarette smoke (CS)-exposed cynomolgus macaque as a nonhuman primate (NHP) large animal model of COPD. Twenty-eight NHPs were exposed to air or CS 5 days per week for up to 12 weeks. Bronchoalveolar lavage and pulmonary function tests were performed at intervals. After 12 weeks, we measured airway pathologies, pulmonary inflammation, and airspace enlargement. CS-exposed NHPs developed robust mucus metaplasia, submucosal gland hypertrophy and hyperplasia, airway inflammation, peribronchial fibrosis, and increases in bronchial lymphoid aggregates. Although CS-exposed NHPs did not develop emphysema over the study time, they exhibited pathologies that precede emphysema development, including increases in the following: i) matrix metalloproteinase-9 and proinflammatory mediator levels in bronchoalveolar lavage fluid, ii) lung parenchymal leukocyte counts and lymphoid aggregates, iii) lung oxidative stress levels, and iv) alveolar septal cell apoptosis. CS-exposed NHPs can be used as a model of airway disease occurring in COPD patients. Unlike rodents, NHPs can safely undergo longitudinal sampling, which could be useful for assessing novel biomarkers or therapeutics for COPD.

Mononuclear phagocytes and airway epithelial cells: novel sources of matrix metalloproteinase-8 (MMP-8) in patients with idiopathic pulmonary fibrosis

Objectives

Matrix metalloproteinase-8 (MMP-8) promotes lung fibrotic responses to bleomycin in mice. Although prior studies reported that MMP-8 levels are increased in plasma and bronchoalveolar lavage fluid (BALF) samples from IPF patients, neither the bioactive forms nor the cellular sources of MMP-8 in idiopathic pulmonary fibrosis (IPF) patients have been identified. It is not known whether MMP-8 expression is dys-regulated in IPF leukocytes or whether MMP-8 plasma levels correlate with IPF outcomes. Our goal was to address these knowledge gaps.

Methods

We measured MMP-8 levels and forms in blood and lung samples from IPF patients versus controls using ELISAs, western blotting, and qPCR, and assessed whether MMP-8 plasma levels in 73 IPF patients correlate with rate of lung function decline and mortality. We used immunostaining to localize MMP-8 expression in IPF lungs. We quantified MMP-8 levels and forms in blood leukocytes from IPF patients versus controls.

Results

IPF patients have increased BALF, whole lung, and plasma levels of soluble MMP-8 protein. Active MMP-8 is the main form elevated in IPF lungs. MMP-8 mRNA levels are increased in monocytes from IPF patients, but IPF patients and controls have similar levels of MMP-8 in PMNs. Surprisingly, macrophages and airway epithelial cells are the main cells expressing MMP-8 in IPF lungs. Plasma and BALF MMP-8 levels do not correlate with decline in lung function and/or mortality in IPF patients.

Conclusion

Blood and lung MMP-8 levels are increased in IPF patients. Active MMP-8 is the main form elevated in IPF lungs. Surprisingly, blood monocytes, lung macrophages, and airway epithelial cells are the main cells in which MMP-8 is upregulated in IPF patients. Plasma and BALF MMP-8 levels are unlikely to serve as a prognostic biomarker for IPF patients. These results provide new information about the expression patterns of MMP-8 in IPF patients.

Disease progression in young patients with COPD: rethinking the Fletcher and Peto model

Chronic obstructive pulmonary disease (COPD), although frequent in older individuals, can also occur at younger age; this latter population has not been well described. We reviewed the functional progression of 1708 patients with COPD attending pulmonary clinics. Those with three or more annual spirometries were divided into those who, at enrolment, were ≤ 55 (n = 103) or ≥ 65 (n = 463) years of age (younger and older COPD, respectively). Baseline and annual changes in lung function (forced expiratory volume in 1 s (FEV1)) and BODE (body mass index, airflow obstruction, dyspnoea, exercise capacity) score were recorded and compared between both groups. Severity distribution by Global Initiative for Chronic Obstructive Lung Disease and BODE scores were similar in both groups, except for mild obstruction, which was higher in the younger group. Mean FEV1 decline was 38.8 and 40.6 mL · year(-1), while BODE scores increased 0.19 and 0.23 units per year, for younger and older COPD, respectively. Both groups had similar proportion of FEV1 rapid decliners (42% and 46%, respectively). The severity distribution and progression of disease in younger patients with COPD is similar to that of patients of older age. This observation suggests that younger individuals presenting with COPD develop the disease from an already compromised pulmonary and systemic status, complementing the model of steeper decline of lung function proposed by Fletcher and Peto.

Rapid lung function decline in smokers is a risk factor for COPD and is attenuated by angiotensin-converting enzyme inhibitor use

OBJECTIVE

Cigarette smoking is the most important risk factor for COPD in the United States. Host factors that influence the rapid rate of FEV1 decline in smokers and how decline rate influences risk for developing COPD are unknown. The aim of this study was to characterize the rate of FEV1 decline in ever smokers, compare the risk of incident COPD between those with rapid decline and others, and determine the effect of selected drugs on rapid decline.

METHODS

A total of 1,170 eligible ever smokers from the longitudinal Lovelace Smokers Cohort with repeat spirometry tests over a minimum follow-up period of 3 years (mean follow-up, 5.9 years) were examined, including 809 ever smokers without a spirometric abnormality at baseline. Longitudinal absolute decline in postbronchodilator FEV1 from the slope of the spirometric values over all examinations was annualized and classified as rapid (≥30 mL/y), normal (0-29.9 mL/y), or no (>0 mL/y) decline. Logistic regression and Kaplan-Meier survival curves were used for the analysis.

RESULTS

Approximately 32% of ever smokers exhibited rapid decline. Among ever smokers without a baseline spirometric abnormality, rapid decline was associated with an increased risk for incident COPD (OR, 1.88; P=.003). The use of angiotensin-converting enzyme (ACE) inhibitors at baseline examination was protective against rapid decline, particularly among those with comorbid cardiovascular disease, hypertension, or diabetes (ORs 0.48, 0.48, and 0.12, respectively; P≤.02 for all analyses).

CONCLUSIONS

Ever smokers with a rapid decline in FEV1 are at higher risk for COPD. Use of ACE inhibitors by smokers may protect against this rapid decline and the progression to COPD.

Factors associated with bronchiolitis obliterans syndrome and chronic graft-versus-host disease after allogeneic hematopoietic cell transplantation

Bronchiolitis obliterans syndrome (BOS) is a form of chronic graft vs. host disease (cGVHD) and a highly morbid pulmonary complication after allogeneic hematopoietic stem cell transplantation (HSCT). We assessed the prevalence and risk factors for BOS and cGVHD in a cohort of HSCT recipients, including those who received reduced intensity conditioning (RIC) HSCT. Between January 1, 2000 and June 30, 2010, all patients who underwent allogeneic HSCT at our institution (n = 1854) were retrospectively screened for the development of BOS by PFT criteria. We matched the BOS cases with two groups of control patients: (1) patients who had concurrent cGVHD without BOS and (2) those who developed neither cGVHD nor BOS. Comparisons between BOS patients and controls were conducted using t-test or Fisher's exact tests. Multivariate regression analysis was performed to examine factors associated with BOS diagnosis. All statistical analyses were performed using SAS 9.2. We identified 89 patients (4.8%) meeting diagnostic criteria for BOS at a median time of 491 days (range: 48-2067) after HSCT. Eighty-six (97%) of our BOS cohort had extra-pulmonary cGVHD. In multivariate analysis compared to patients without cGVHD, patients who received busulfan-based conditioning, had unrelated donors, and had female donors were significantly more likely to develop BOS, while ATG administration was associated with a lower risk of BOS. Our novel results suggest that busulfan conditioning, even in RIC transplantation, could be an important risk factor for BOS and cGVHD.

Obstructive lung disease in Mexican Americans and non-Hispanic whites: an analysis of diagnosis and survival in the National Health and Nutritional Examination Survey III Follow-up Study

BACKGROUND

Although obstructive lung disease (OLD), which includes COPD, affects all the populations, Hispanics seem to be protected against COPD development and progression. Whether this advantage translates into a survival benefit for this population is unknown. We aimed to determine the risk for OLD in Mexican Americans, the largest US Hispanic subgroup, compared with non-Hispanic whites and to assess all-cause mortality in subjects with OLD.

METHODS

We assessed the relationships between Mexican American ethnicity and spirometric OLD and risk of death among 6,456 US adults aged ≥ 40 years who participated in the Third National Health and Nutritional Examination Survey Follow-up Study. We used logistic and Cox regression analyses to estimate the OR for OLD among Mexican Americans and the hazard ratio (HR) for all-cause mortality among Mexican Americans with OLD, respectively.

RESULTS

After adjustment for demographic factors, socioeconomic status, and COPD risk factors, Mexican Americans had decreased odds of OLD diagnosis compared with whites (OR, 0.72 [95% CI, 0.54-0.95]). Among the 1,734 participants with OLD, 1,054 (60.8%) died during median follow-up of 12 years. In an adjusted model, Mexican Americans had no advantage in mortality from all causes (HR, 0.88 [95% CI, 0.69-1.13]). After accounting for the fact that some Mexican Americans may have moved back to Mexico and died there (thus, had no US death certificate), there was still no difference in mortality between these groups.

CONCLUSIONS

Although Mexican Americans appear to have lower risk for OLD, subjects of this ethnicity with OLD do not seem to have a survival advantage.

Longitudinal assessment in COPD patients: multidimensional variability and outcomes

The value and timing of multidimensional assessments in chronic obstructive pulmonary disease (COPD) remains unclear because there is little information about their variability and relationship to outcome. The aim of this study was to determine the progression of COPD using clinical and spirometric variability over time with mortality as the outcome. We determined the annual intra-individual variability of forced expiratory volume in 1 s (FEV1) and BODE (body mass index, airflow obstruction, dyspnoea, exercise capacity) index in 403 patients with at least five measurements. The pattern was defined as "stable" if the annual change remained constant in ≥66% of the observations and "unstable" if it did not meet that threshold. We explored the minimum number of yearly observations that related to mortality in the 704 patients of the cohort. The "unstable" pattern of FEV1 was seen in 53% and 40% of patients using a threshold of 40 mL·year(-1) and 100 mL·year(-1), respectively. There was a slightly more "stable" pattern in the BODE index (62% for 1 point). A profile associated with mortality was defined by a baseline measurement followed by annual measurements for 2 years of the BODE index, but not its individual components, including FEV1 (p<0.001). Progression of COPD measured using FEV1 is inconsistent and relates poorly to outcome. Monitoring the more stable BODE index better assesses disease progression.

The expanding role of biomarkers in the assessment of smoking-related parenchymal lung diseases

Recent advances in the field of clinical biomarkers suggest that quantification of serum proteins could play an important role in the diagnosis, classification, prognosis, and treatment response of smoking-related parenchymal lung diseases. COPD and idiopathic pulmonary fibrosis (IPF), two common chronic progressive parenchymal lung diseases, share cigarette smoke exposure as a common dominant risk factor for their development. We have recently shown that COPD and interstitial lung disease may represent distinct outcomes of chronic tobacco use, whereas others have demonstrated that both diseases coexist in some individuals. In this perspective, we examine the potential role of peripheral blood biomarkers in predicting which individuals will develop COPD or IPF, as well as their usefulness in tracking disease progression and exacerbations. Additionally, given the current lack of sensitive and effective metrics to determine an individual's response to treatment, we evaluate the potential role of biomarkers as surrogate markers of clinical outcomes. Finally, we examine the possibility that changes in levels of select protein biomarkers can provide mechanistic insight into the common origins and unique individual susceptibilities that lead to the development of smoking-related parenchymal lung diseases. This discussion is framed by a consideration of the properties of ideal biomarkers for different clinical and research purposes and the best uses for those biomarkers that have already been proposed and investigated.

Comparison of arterial and venous blood biomarker levels in chronic obstructive pulmonary disease

Purpose: The development of novel biomarkers is an unmet need in chronic obstructive pulmonary disease (COPD). Arterial blood comes directly from the lung and venous blood drains capillary beds of the organ or tissue supplied. We hypothesized that there would be a difference in levels of the biomarkers metalloproteinase 9 (MMP-9), vascular endothelial growth factor A (VEGF-A) and interleukin 6 (IL-6) in arterial compared with venous blood. 

Methods: Radial artery and brachial vein blood samples were taken simultaneously in each of 12 patients with COPD and seven controls with normal lung function. Circulating immunoreactive MMP-9, VEGF-A and IL-6 levels in serum were measured using quantitative enzyme-linked immunosorbent assays. Results were compared using a Student’s paired t test. The study was powered to determine whether significant differences in cytokine levels were present between paired arterial and venous blood samples.  

Results: In the 12 patients with COPD, four were female, and age ranged 53-85 years, mean age 69 years. Three patients in the control group were female, with age range 46-84 years, mean age 64.7 years. In the COPD group, three patients had mild, five moderate and four severe COPD. No significant difference was found between arterial and venous levels of MMP-9, VEGF-A or IL-6. 

Conclusions: In this pilot study, levels of the measured biomarkers in arterial compared with venous blood in both COPD patients and healthy controls did not differ. This suggests that as we continue to chase the elusive biomarker in COPD as a potential tool to measure disease activity, we should focus on venous blood for this purpose.

Inflammatory and repair serum biomarker pattern: association to clinical outcomes in COPD

Background

The relationship between serum biomarkers and clinical expressions of COPD is limited. We planned to further describe this association using markers of inflammation and injury and repair.

Methods

We studied lung function, comorbidities, exercise tolerance, BODE index, and quality of life in 253 COPD patients and recorded mortality over three years. Serum levels of Interleukins 6,8 and16, tumor necrosis factor alpha (TNF α) [inflammatory panel], vascular endothelial growth factor (VEGF), and matrix metalloproteinase 9 (MMP-9) [injury and repair panel] and pulmonary and activation-regulated chemokine (PARC/CCL-18) and monocyte chemotactic protein 1 (MCP-1/CCL2) [chemoattractant panel] were measured. We related the pattern of the biomarker levels to minimal clinically important differences (MCID) using a novel visualization method [ObServed Clinical Association Results (OSCAR) plot].

Results

Levels of the inflammatory markers IL-6, TNF α were higher and those of injury and repair lower (p < 0.01) with more advanced disease (GOLD 1 vs. 4). Using the OSCAR plot, we found that patients in the highest quartile of inflammatory and lowest quartile of injury and repair biomarkers level were more clinically compromised and had higher mortality (p < 0.05).

Conclusions

In COPD, serum biomarkers of inflammation and repair are distinctly associated with important clinical parameters and survival.

Role of exercise in testing and in therapy of COPD

The stair-climbing test, 6MWT, and shuttle test are exercise tests that requires less technical support than the CPET and are more available to any physician. The 6MWT is the simplest and most likely to be cost effective, as it provides useful information regarding prognosis, ADLs, and health care use at a very low cost. In addition, the 6MWT can be used to evaluate response to several interventions, including physical rehabilitation, medications, lung volume reduction interventions, and transplantation. The 6MWT has also been useful in and has become an integral part of the evaluation and response to treatment in other medical conditions, including congestive heart failure, pulmonary hypertension, and pulmonary fibrosis. The stair-climbing test seems to be most useful for preoperative evaluations when a CPET is not available. We have also used it on patients unable to perform a good CPET because of lack of familiarity with bicycle pedaling. The shuttle walk test may be used to better determine a maximal exercise capacity when a CPET is not available and to measure the effects of pulmonary rehabilitation in patients unfamiliar with a CPET. The role of exercise as a therapeutic tool is central to the concept of pulmonary rehabilitation. Exercise training improves not only functional dyspnea and health-related quality of life, but also has been shown to decrease health care resource use. As part of a comprehensive pulmonary rehabilitation initiated after a hospitalization for exacerbation, it has been shown to decrease readmission rates.

Comorbidities and risk of mortality in patients with chronic obstructive pulmonary disease

RATIONALE

Patients with chronic obstructive pulmonary disease (COPD) are afflicted by comorbidities. Few studies have prospectively evaluated COPD comorbidities and mortality risk.

OBJECTIVES

To prospectively evaluate COPD comorbidities and mortality risk.

METHODS

We followed 1,664 patients with COPD in five centers for a median of 51 months. Systematically, 79 comorbidities were recorded. We calculated mortality risk using Cox proportional hazard, and developed a graphic representation of the prevalence and strength of association to mortality in the form of a "comorbidome". A COPD comorbidity index (COPD specific comorbidity test [COTE]) was constructed based on the comorbidities that increase mortality risk using a multivariate analysis. We tested the COTE index as predictor of mortality and explored whether the COTE index added predictive information when used with the validated BODE index.

MEASUREMENTS AND MAIN RESULTS

Fifteen of 79 comorbidities differed in prevalence between survivors and nonsurvivors. Of those, 12 predicted mortality and were integrated into the COTE index. Increases in the COTE index were associated with an increased risk of death from COPD-related (hazard ratio [HR], 1.13; 95% confidence interval, 1.08-1.18; P < 0.001) and non-COPD-related causes (HR, 1.18; 95% confidence interval, 1.15-1.21; P < 0.001). Further, increases in the BODE and COTE were independently associated with increased risk of death. A COTE score of greater than or equal to 4 points increased by 2.2-fold the risk of death (HR, 2.26-2.68; P < 0.001) in all BODE quartile.

CONCLUSIONS

Comorbidities are frequent in COPD and 12 of them negatively influence survival. A simple disease-specific comorbidities index (COTE) helps assess mortality risk in patients with COPD.

Predicting outcomes from 6-minute walk distance in chronic obstructive pulmonary disease

BACKGROUND

Exercise tolerance is an important clinical aspect of chronic obstructive pulmonary disease that can be easily and reliably measured with the 6-minute walking test (6MWT). To improve the utility of the 6MWT for patient and health care system management, the interpretation of the functional status measure in relation to death and hospitalization should be elucidated.

METHODS

Three-year, prospective, multicenter observational study to evaluate the predictive power of 6MWD for death or exacerbation-related hospitalization and to evaluate the factors that help determine 6MWD.

RESULTS

We measured 6MWD at baseline and annually in 2110 patients with clinically stable Global Initiative for Obstructive Lung Disease (GOLD) stage II-IV COPD and recorded exacerbation-related hospitalizations and all-cause mortality. During the study, 200 patients died and 650 were hospitalized. Using receiver operating characteristics, the best predictive thresholds of the 6MWD were 334 m for increased risk of death and 357 m for exacerbation-related hospitalization (area under the curve 0.67 and 0.60 respectively); however, the discriminatory thresholds, especially for mortality, were influenced by age. The mean (SE) 6MWD declined by 1.6 (1.2) m per year in GOLD II, 9.8 (1.3) m per year in GOLD III, and 8.5 (2.4) m per year in GOLD IV.

CONCLUSION

The 6MWD provides prognostic information that may be useful for identifying high-risk patients with COPD.