The role of chest computed tomography in the evaluation and management of chronic obstructive pulmonary disease

PURPOSE OF REVIEW

The purpose of this review is to compile recent data on the clinical associations of computed tomography (CT) scan findings in the literature and potential avenues for implementation into clinical practice.

RECENT FINDINGS

Airways dysanapsis, emphysema, chronic bronchitis, and pulmonary vascular metrics have all recently been associated with poor chronic obstructive pulmonary disease (COPD) outcomes when controlled for clinically relevant covariables, including risk of mortality in the case of emphysema and chronic bronchitis. Other authors suggest that CT scan may provide insight into both lung parenchymal damage and other clinically important comorbidities in COPD.

SUMMARY

CT scan findings in COPD relate to clinical outcomes. There is a continued need to develop processes to best implement the results of these studies into clinical practice.

Predicting Adverse Events Among Patients With COPD Exacerbations in the Emergency Department

BACKGROUND

COPD exacerbations lead to excessive health care utilization, morbidity, and mortality. The Ottawa COPD Risk Scale (OCRS) was developed to predict short-term serious adverse events (SAEs) among patients in the emergency department (ED) with COPD exacerbations. We assessed the utility of the OCRS, its component elements, and other clinical variables for ED disposition decisions in a United States population.

METHODS

We compared the OCRS and other factors in predicting SAEs among a retrospective cohort of ED patients with COPD exacerbations. We followed subjects for 30 d, and the primary outcome, SAE, was defined as any death, admission to monitored unit, intubation, noninvasive ventilation, major procedure, myocardial infarction, or revisit with hospital admission.

RESULTS

A total of 246 subjects (median 61-y old, 46% male, total admission rate to ward 52%) were included, with 46 (18.7%) experiencing SAEs. Median OCRS scores did not differ significantly between those with and without an SAE (difference: 0 [interquartile range 0-1)]. The OCRS predicted SAEs poorly (Hosmer-Lemeshow goodness of fit [H-L GOF] P ≤ .001, area under the receiver operating characteristic [ROC] curve 0.519). Three variables were significantly related to SAEs in our final model (H-L GOF P = .14, area under the ROC curve 0.808): Charlson comorbidity index (odds ratio [OR] 1.3 [1.1-1.5] per 1-point increase); triage venous P_CO2 (OR 1.7 [1.2-2.4] per 10 mm Hg increase); and hospitalization within previous year (OR 9.1 [3.3-24.8]).

CONCLUSIONS

The OCRS did not reliably predict SAEs in our population. We found 3 risk factors that were significantly associated with 30-d SAE in our United States ED population: triage P_CO2 level, Charlson comorbidity index, and hospitalization within the previous year. Further studies are needed to develop generalizable decision tools to improve safety and resource utilization for this patient population.

Oral Positive Expiratory Pressure Device for Excessive Dynamic Airway Collapse Caused by Emphysema

Excessive dynamic airway collapse (EDAC) contributes to breathlessness and reduced quality of life in individuals with emphysema. We tested a novel, portable, oral positive expiratory pressure (o-PEP) device in a patient with emphysema and EDAC. MRI revealed expiratory tracheal narrowing to 80 mm² that increased to 170 mm² with the o-PEP device. After 2-weeks use of the o-PEP device for 33% to 66% of activities, breathlessness, quality of life, and exertional dyspnea improved compared with minimal clinically important differences (MCID): University of California-San Diego Shortness of Breath questionnaire score declined 69 to 42 (MCID, ≥5), St. George's Respiratory Questionnaire score decreased 71 to 27 (MCID, ≥4), and before and after the 6-minute walk test Borg score difference improved from Δ3 to Δ2 (MCID, ≥1). During the 6-minute walk test on room air without the use of the o-PEP device, oxyhemoglobin saturation declined 91% to 83%; whereas, with the o-PEP device, the nadir was 90%. Use of the o-PEP device reduced expiratory central airway collapse and improved dyspnea, quality of life, and exertional desaturation in a patient with EDAC and emphysema.

How might endotyping guide chronic obstructive pulmonary disease treatment? Current understanding, knowledge gaps and future research needs

PURPOSE OF REVIEW

This review discusses emerging therapies directed at chronic obstructive pulmonary disease (COPD) endotypes and pathobiological processes that manifest as the disease.

RECENT FINDINGS

Specific endotypes have been targeted in COPD. These include eosinophilic inflammation, overproduction of interleukin-17, chronic bronchitis and altered nature of mucous, and chronic infection. Therapies exactly directed at the cause of these endotypes or their resultant clinical findings have been assessed. Although some intermediate outcomes have seemed promising, there have been no findings that shift the paradigm of COPD therapy.

SUMMARY

Basic and clinical scientists continue to define endotypes that may be directly addressed with therapeutics. As of the time of this up-to-date review, there is yet to be an endotype-directed therapy to demonstrate great clinical effect.

The STS case study: an analysis method for longitudinal qualitative research for implementation science

BACKGROUND

Ethnographic approaches offer a method and a way of thinking about implementation. This manuscript applies a specific case study method to describe the impact of the longitudinal interplay between implementation stakeholders. Growing out of science and technology studies (STS) and drawing on the latent archaeological sensibilities implied by ethnographic methods, the STS case-study is a tool for implementors to use when a piece of material culture is an essential component of an innovation.

METHODS

We conducted an ethnographic process evaluation of the clinical implementation of tele-critical care (Tele-CC) services in the Department of Veterans Affairs. We collected fieldnotes and conducted participant observation at virtual and in-person education and planning events (n = 101 h). At Go-Live and 6-months post-implementation, we conducted site visits to the Tele-CC hub and 3 partnered ICUs. We led semi-structured interviews with ICU staff at Go-Live (43 interviews with 65 participants) and with ICU and Tele-CC staff 6-months post-implementation (44 interviews with 67 participants). We used verification strategies, including methodological coherence, appropriate sampling, collecting and analyzing data concurrently, and thinking theoretically, to ensure the reliability and validity of our data collection and analysis process.

RESULTS

The STS case-study helped us realize that we must think differently about how a Tele-CC clinician could be noticed moving from communal to intimate space. To understand how perceptions of surveillance impacted staff acceptance, we mapped the materials through which surveillance came to matter in the stories staff told about cameras, buttons, chimes, motors, curtains, and doorbells.

CONCLUSIONS

STS case-studies contribute to the literature on longitudinal qualitive research (LQR) in implementation science, including pen portraits and periodic reflections. Anchored by the material, the heterogeneity of an STS case-study generates questions and encourages exploring differences. Begun early enough, the STS case-study method, like periodic reflections, can serve to iteratively inform data collection for researchers and implementors. The next step is to determine systematically how material culture can reveal implementation barriers and direct attention to potential solutions that address tacit, deeply rooted challenges to innovations in practice and technology.

Ultra Long-Acting β-Agonists in Chronic Obstructive Pulmonary Disease

Introduction

Inhaled β-agonists have been foundational medications for maintenance COPD management for decades. Through activation of cyclic adenosine monophosphate pathways, these agents relax airway smooth muscle and improve expiratory airflow by relieving bronchospasm and alleviating air trapping and dynamic hyperinflation improving breathlessness, exertional capabilities, and quality of life. β-agonist drug development has discovered drugs with increasing longer durations of action: short acting (SABA) (4-6 h), long acting (LABA) (6-12 h), and ultra-long acting (ULABA) (24 h). Three ULABAs, indacaterol, olodaterol, and vilanterol, are approved for clinical treatment of COPD.

Purpose

This article reviews both clinically approved ULABAs and ULABAs in development.

Conclusion

Indacaterol and olodaterol were originally approved for clinical use as monotherapies for COPD. Vilanterol is the first ULABA to be approved only in combination with other respiratory medications. Although there are many other ULABA's in various stages of development, most clinical testing of these novel agents is suspended or proceeding slowly. The three approved ULABAs are being combined with antimuscarinic agents and corticosteroids as dual and triple agent treatments that are being tested for clinical use and efficacy. Increasingly, these clinical trials are using specific COPD clinical characteristics to define study populations and to begin to develop therapies that are trait-specific.

Resting Borg score as a predictor of safe discharge of chronic obstructive pulmonary disease from the emergency department observation unit

BACKGROUND

Chronic obstructive pulmonary disease exacerbations (eCOPD) can be life-threatening and costly. Emergency department (ED) observation units (ED-Obs) offer short-term care to safely reduce preventable hospitalizations. Accurately identifying eCOPD patients who can be discharged safely will improve outcomes.

OBJECTIVES

The objective were to: I) evaluate utility of conventional clinical variables as predictors of safe discharge and II) assess utility of serial resting Borg score and novel Dyspnea Assessment Score (DAS) for identifying eCOPD patients who can be safely discharged from ED-Obs.

METHODS

This study was carried out in a 680-bed tertiary, academic hospital with >700 annual eCOPD ED encounters and a 16-bed ED-Obs. A two-phase study of eCOPD patients admitted to ED-Obs was performed. Objective I was a retrospective study including all eCOPD admits from April 2016 to May 2017. Predictor variables (demographics, COPD severity, comorbid conditions, exacerbation severity, clinical care in ED) and outcome variables (ED-Obs disposition, ED revisits) were obtained through electronic medical records. Safe discharge was defined as home disposition from ED-Obs without 7-day revisit. A stepwise regression was performed for predictors of safe discharge. Objective II was a prospective observation study for change in every 4-hour serial resting Borg score and DAS as identifiers of safe discharge. Comparative and receiver operating characteristic (ROC) analyses were performed. A p-value of <0.05 was considered significant.

RESULTS

In Objective I, 171 patients with age, FEV₁ %, and body mass index of 59.8 (±9.5) years, 35 (±24)%, and 28.8 (±8) m² /kg were included. After ED-Obs treatment 78 (45.6%) were hospitalized and 93 (54.4%) were discharged home, of whom 11 (6.4%) had 7-day ED revisit. Safe discharge occurred in 82 (48%). None of the predictor variables correlated with safe discharge. In Objective II, of 38 patients included, 20 (52.6%) had safe discharge. Among others, 16 (42%) were hospitalized and two (5.2%) had 7-day ED revisit. The admission Borg scores and DASs were similar in both groups. The predisposition Borg score was significantly lower in patients with safe discharge (2.75 vs. 5.28, p < 0.001) and had the highest area under curve on ROC (0.77) for safe discharge. DAS was not significantly different between groups.

CONCLUSIONS

Routine clinical variables do not identify eCOPD patients who can be safely discharged from ED-Obs. Change in resting Borg score during the course of ED-Obs treatment safely identifies patients for discharge. Prospective, external validation is needed to incorporate serial Borg scores in ED-Obs disposition decision for improved safety.

COPD Care Bundle in Emergency Department Observation Unit Reduces Emergency Department Revisits

BACKGROUND

COPD exacerbations lead to accelerated decline in lung function, poor quality of life, and increased mortality and cost. Emergency department (ED) observation units provide short-term care to reduce hospitalizations and cost. Strategies to improve outcomes in ED observation units following COPD exacerbations are needed. We sought to reduce 30-d ED revisits for COPD exacerbations managed in ED observation units through implementation of a COPD care bundle. The study setting was an 800-bed, academic, safety-net hospital with 700 annual ED encounters for COPD exacerbations. Among those discharged from ED observation unit, the 30-d all-cause ED revisit rate (ie, the outcome measure) was 49% (baseline period: August 2014 through September 2016).

METHODS

All patients admitted to the ED observation unit with COPD exacerbations were included. A multidisciplinary team implemented the COPD bundle using iterative plan-do-study-act cycles with a goal adherence of 90% (process measure). The bundle, adopted from our inpatient program, was developed using care-delivery failures and unmet subject needs. It included 5 components: appropriate inhaler regimen, 30-d inhaler supply, education on devices available after discharge, standardized discharge instructions, and a scheduled 15-d appointment. We used statistical process-control charts for process and outcome measures. To compare subject characteristics and process features, we sampled consecutive patients from the baseline (n = 50) and postbundle (n = 83) period over 5-month and 7-month intervals, respectively. Comparisons were made using t tests and chi-square tests with P < .05 significance.

RESULTS

During baseline and postbundle periods, 410 and 165 subjects were admitted to the ED observation unit, respectively. After iterative plan-do-study-act cycles, bundle adherence reached 90% in 6 months, and the 30-d ED revisit rate declined from 49% to 30% (P = .003) with a system shift on statistical process-control charts. There was no difference in hospitalization rate from ED observation unit (45% vs 51%, P = .16). Subject characteristics were similar in the baseline and postbundle periods.

CONCLUSIONS

Reliable adherence to a COPD care bundle reduced 30-d ED revisits among those treated in the ED observation unit.

Serum IgG Levels and Risk of COPD Hospitalization: A Pooled Meta-analysis

BACKGROUND

Hypogammaglobulinemia (serum IgG levels < 7.0 g/L) has been associated with increased risk of COPD exacerbations but has not yet been shown to predict hospitalizations.

RESEARCH QUESTION

To determine the relationship between hypogammaglobulinemia and the risk of hospitalization in patients with COPD.

STUDY DESIGN AND METHODS

Serum IgG levels were measured on baseline samples from four COPD cohorts (n = 2,259): Azithromycin for Prevention of AECOPD (MACRO, n = 976); Simvastatin in the Prevention of AECOPD (STATCOPE, n = 653), Long-Term Oxygen Treatment Trial (LOTT, n = 354), and COPD Activity: Serotonin Transporter, Cytokines and Depression (CASCADE, n = 276). IgG levels were determined by immunonephelometry (MACRO; STATCOPE) or mass spectrometry (LOTT; CASCADE). The effect of hypogammaglobulinemia on COPD hospitalization risk was evaluated using cumulative incidence functions for this outcome and deaths (competing risk). Fine-Gray models were performed to obtain adjusted subdistribution hazard ratios (SHR) related to IgG levels for each study and then combined using a meta-analysis. Rates of COPD hospitalizations per person-year were compared according to IgG status.

RESULTS

The overall frequency of hypogammaglobulinemia was 28.4%. Higher incidence estimates of COPD hospitalizations were observed among participants with low IgG levels compared with those with normal levels (Gray's test, P < .001); pooled SHR (meta-analysis) was 1.29 (95% CI, 1.06-1.56, P = .01). Among patients with prior COPD admissions (n = 757), the pooled SHR increased to 1.58 (95% CI, 1.20-2.07, P < .01). The risk of COPD admissions, however, was similar between IgG groups in patients with no prior hospitalizations: pooled SHR = 1.15 (95% CI, 0.86-1.52, P =.34). The hypogammaglobulinemia group also showed significantly higher rates of COPD hospitalizations per person-year: 0.48 ± 2.01 vs 0.29 ± 0.83, P < .001.

INTERPRETATION

Hypogammaglobulinemia is associated with a higher risk of COPD hospital admissions.

Evaluation of clinician interaction with alerts to enhance performance of the tele-critical care medical environment

OBJECTIVE

Identify opportunities to improve the interaction between clinicians and Tele-Critical Care (Tele-CC) programs through an analysis of alert occurrence and reactivation in a specific Tele-CC application.

MATERIALS AND METHODS

Data were collected automatically through the Philips eCaremanager® software system used at multiple hospitals in the Avera health system. We evaluated the distribution of alerts per patient, frequency of alert types, time between consecutive alerts, and Tele-CC clinician choice of alert reactivation times.

RESULTS

Each patient generated an average of 79.8 alerts during their ICU stay (median 31.0; 25th - 75th percentile 10.0-89.0) with 46.4 for blood pressure and 38.4 for oxygenation. The most frequent alerts for continuous physiological parameters were: MAP limit (28.9 %), O₂/RR (26.4 %), MAP trend (16.5 %), HR trend (12.1 %), and HR limit (11.3 %). The median time between consecutive alerts for one parameter was less than 10 min for 86 % of patients. Tele-CC providers responded to all alert types with immediate reactivation 47-88 % of the time. Limit alerts had longer reactivation times than their trend alert counterparts (p-value < .001).

CONCLUSIONS

The alert type specific differences in frequency, time occurrence and provider choice of reactivation time provide insight into how clinicians interact with the Tele-CC system. Systems engineering enhancements to Tele-CC software algorithms may reduce alert burden and thereby decrease clinicians' cognitive workload for alert assessment. Further study of Tele-CC alert generation, alert presentation to clinicians, and the clinicians' options to respond to these alerts may reduce provider workload, minimize alert desensitization, and optimize the ability of Tele-CC clinicians to provide efficient and timely critical care management.

Association of Guideline-Recommended COPD Inhaler Regimens With Mortality, Respiratory Exacerbations, and Quality of Life: A Secondary Analysis of the Long-Term Oxygen Treatment Trial

BACKGROUND

Although inhaled therapy reduces exacerbations among patients with COPD, the effectiveness of providing inhaled treatment per risk stratification models remains unclear.

RESEARCH QUESTION

Are inhaled regimens that align with the 2017 Global Initiative for Chronic Obstructive Lung Disease (GOLD) strategy associated with clinically important outcomes?

STUDY DESIGN AND METHODS

We conducted secondary analyses of Long-term Oxygen Treatment Trial (LOTT) data. The trial enrolled patients with COPD with moderate resting or exertional hypoxemia between 2009 and 2015. Our exposure was the patient-reported inhaled regimen at enrollment, categorized as either aligning with, undertreating, or potentially overtreating per the 2017 GOLD strategy. Our primary composite outcome was time to death or first hospitalization for COPD. Additional outcomes included individual components of the composite outcome and time to first exacerbation. We generated multivariable Cox proportional hazard models across strata of GOLD-predicted exacerbation risk (high vs low) to estimate between-group hazard ratios for time to event outcomes. We adjusted models a priori for potential confounders, clustered by site.

RESULTS

The trial enrolled 738 patients (73.4% men; mean age, 68.8 years). Of the patients, 571 (77.4%) were low risk for future exacerbations. Of the patients, 233 (31.6%) reported regimens aligning with GOLD recommendations; most regimens (54.1%) potentially overtreated. During a 2.3-year median follow-up, 332 patients (44.9%) experienced the composite outcome. We found no difference in time to composite outcome or death among patients reporting regimens aligning with recommendations compared with undertreated patients. Among patients at low risk, potential overtreatment was associated with higher exacerbation risk (hazard ratio, 1.42; 95% CI, 1.09-1.87), whereas inhaled corticosteroid treatment was associated with 64% higher risk of pneumonia (incidence rate ratio, 1.64; 95% CI, 1.01-2.66).

INTERPRETATION

Among patients with COPD with moderate hypoxemia, we found no difference in clinical outcomes between inhaled regimens aligning with the 2017 GOLD strategy compared with those that were undertreated. These findings suggest the need to reevaluate the effectiveness of risk stratification model-based inhaled treatment strategies.

Unique natural killer cell subpopulations are associated with exacerbation risk in chronic obstructive pulmonary disease

Chronic Obstructive Pulmonary Disease (COPD) is the third leading cause of death worldwide. COPD is frequently punctuated by acute exacerbations that are precipitated primarily by infections, which increase both morbidity and mortality and inflates healthcare costs. Despite the significance of exacerbations, little understanding of immune function in COPD exacerbations exists. Natural killer (NK) cells are important effectors of innate and adaptive immune responses to pathogens and NK cell function is altered in smokers and COPD. Using high-dimensional flow cytometry, we phenotyped peripheral blood NK cells from never smokers, smokers, and COPD patients and employed a non-supervised clustering algorithm to define and detect changes in NK cell populations. We identified greater than 1,000 unique NK cell subpopulations across patient groups and describe 13 altered NK populations in patients who experienced prior exacerbations. Based upon cluster sizes and associated fluorescence data, we generated a logistic regression model to predict patients with a history of exacerbations with high sensitivity and specificity. Moreover, highly enriched NK cell subpopulations implicated in the regression model exhibited enhanced effector functions as defined by in vitro cytotoxicity assays. These novel data reflect the effects of smoking and disease on peripheral blood NK cell phenotypes, provide insight into the potential immune pathophysiology of COPD exacerbations, and indicate that NK cell phenotyping may be a useful and biologically relevant marker to predict COPD exacerbations.

Utilized or Underutilized: A Qualitative Analysis of Building Coherence During Early Implementation of a Tele-Intensive Care Unit

Background: Generating, reading, or interpreting data is a component of Telemedicine-Intensive Care Unit (Tele-ICU) utilization that has not been explored in the literature. Introduction: Using the idea of "coherence," a construct of Normalization Process Theory, we describe how intensive care unit (ICU) and Tele-ICU staff made sense of their shared work and how they made use of Tele-ICU together. Materials and Methods: We interviewed ICU and Tele-ICU staff involved in the implementation of Tele-ICU during site visits to a Tele-ICU hub and 3 ICUs, at preimplementation (43 interviews with 65 participants) and 6 months postimplementation (44 interviews with 67 participants). Data were analyzed using deductive coding techniques and lexical searches. Results: In the early implementation of Tele-ICU, ICU and Tele-ICU staff lacked consensus about how to share information and consequently how to make use of innovations in data tracking and interpretation offered by the Tele-ICU (e.g., acuity systems). Attempts to collaborate and create opportunities for utilization were supported by quality improvement (QI) initiatives. Discussion: Characterizing Tele-ICU utilization as an element of a QI process limited how ICU staff understood Tele-ICU as an innovation. It also did not promote an understanding of how the Tele-ICU used data and may therefore attenuate the larger promise of Tele-ICU as a potential tool for leveraging big data in critical care. Conclusions: Shared data practices lay the foundation for Tele-ICU program utilization but raise new questions about how the promise of big data can be operationalized for bedside ICU staff.

Metoprolol for the Prevention of Acute Exacerbations of COPD

BACKGROUND

Observational studies suggest that beta-blockers may reduce the risk of exacerbations and death in patients with moderate or severe chronic obstructive pulmonary disease (COPD), but these findings have not been confirmed in randomized trials.

METHODS

In this prospective, randomized trial, we assigned patients between the ages of 40 and 85 years who had COPD to receive either a beta-blocker (extended-release metoprolol) or placebo. All the patients had a clinical history of COPD, along with moderate airflow limitation and an increased risk of exacerbations, as evidenced by a history of exacerbations during the previous year or the prescribed use of supplemental oxygen. We excluded patients who were already taking a beta-blocker or who had an established indication for the use of such drugs. The primary end point was the time until the first exacerbation of COPD during the treatment period, which ranged from 336 to 350 days, depending on the adjusted dose of metoprolol.

RESULTS

A total of 532 patients underwent randomization. The mean (±SD) age of the patients was 65.0±7.8 years; the mean forced expiratory volume in 1 second (FEV1) was 41.1±16.3% of the predicted value. The trial was stopped early because of futility with respect to the primary end point and safety concerns. There was no significant between-group difference in the median time until the first exacerbation, which was 202 days in the metoprolol group and 222 days in the placebo group (hazard ratio for metoprolol vs. placebo, 1.05; 95% confidence interval [CI], 0.84 to 1.32; P = 0.66). Metoprolol was associated with a higher risk of exacerbation leading to hospitalization (hazard ratio, 1.91; 95% CI, 1.29 to 2.83). The frequency of side effects that were possibly related to metoprolol was similar in the two groups, as was the overall rate of nonrespiratory serious adverse events. During the treatment period, there were 11 deaths in the metoprolol group and 5 in the placebo group.

CONCLUSIONS

Among patients with moderate or severe COPD who did not have an established indication for beta-blocker use, the time until the first COPD exacerbation was similar in the metoprolol group and the placebo group. Hospitalization for exacerbation was more common among the patients treated with metoprolol. (Funded by the Department of Defense; BLOCK COPD ClinicalTrials.gov number, NCT02587351.).

The anti-sigma factor MucA of Pseudomonas aeruginosa: Dramatic differences of a mucA22 vs. a ΔmucA mutant in anaerobic acidified nitrite sensitivity of planktonic and biofilm bacteria in vitro and during chronic murine lung infection

Mucoid mucA22 Pseudomonas aeruginosa (PA) is an opportunistic lung pathogen of cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) patients that is highly sensitive to acidified nitrite (A-NO₂^-). In this study, we first screened PA mutant strains for sensitivity or resistance to 20 mM A-NO₂^- under anaerobic conditions that represent the chronic stages of the aforementioned diseases. Mutants found to be sensitive to A-NO₂^- included PA0964 (pmpR, PQS biosynthesis), PA4455 (probable ABC transporter permease), katA (major catalase, KatA) and rhlR (quorum sensing regulator). In contrast, mutants lacking PA0450 (a putative phosphate transporter) and PA1505 (moaA2) were A-NO₂^- resistant. However, we were puzzled when we discovered that mucA22 mutant bacteria, a frequently isolated mucA allele in CF and to a lesser extent COPD, were more sensitive to A-NO₂^- than a truncated ΔmucA deletion (Δ157–194) mutant in planktonic and biofilm culture, as well as during a chronic murine lung infection. Subsequent transcriptional profiling of anaerobic, A-NO₂^--treated bacteria revealed restoration of near wild-type transcript levels of protective NO₂^- and nitric oxide (NO) reductase (nirS and norCB, respectively) in the ΔmucA mutant in contrast to extremely low levels in the A-NO₂^--sensitive mucA22 mutant. Proteins that were S-nitrosylated by NO derived from A-NO₂^- reduction in the sensitive mucA22 strain were those involved in anaerobic respiration (NirQ, NirS), pyruvate fermentation (UspK), global gene regulation (Vfr), the TCA cycle (succinate dehydrogenase, SdhB) and several double mutants were even more sensitive to A-NO₂^-. Bioinformatic-based data point to future studies designed to elucidate potential cellular binding partners for MucA and MucA22. Given that A-NO₂^- is a potentially viable treatment strategy to combat PA and other infections, this study offers novel developments as to how clinicians might better treat problematic PA infections in COPD and CF airway diseases.

A Comparison between Two Pathophysiologically Different yet Microbiologically Similar Lung Diseases: Cystic Fibrosis and Chronic Obstructive Pulmonary Disease

Cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) are chronic pulmonary diseases that affect ~70,000 and 251 million individuals worldwide, respectively. Although these two diseases have distinctly different pathophysiologies, both cause chronic respiratory insufficiency that erodes quality of life and causes significant morbidity and eventually death. In both CF and COPD, the respiratory microbiome plays a major contributing role in disease progression and morbidity. Pulmonary pathogens can differ dramatically during various stages of each disease and frequently cause acute worsening of lung function due to disease exacerbation. Despite some similarities, outcome and timing/type of exacerbation can also be quite different between CF and COPD. Given these clinical distinctions, both patients and physicians should be aware of emerging therapeutic options currently being offered or in development for the treatment of lung infections in individuals with CF and COPD. Although interventions are available that prolong life and mitigate morbidity, neither disorder is curable. Both acute and chronic pulmonary infections contribute to an inexorable downward course and may trigger exacerbations, culminating in loss of lung function or respiratory failure. Knowledge of the pulmonary pathogens causing these infections, their clinical presentation, consequences, and management are, therefore, critical. In this review, we compare and contrast CF and COPD, including underlying causes, general outcomes, features of the lung microbiome, and potential treatment strategies.

Using electronic medical record notes to measure ICU telemedicine utilization

Given the complexity of high-acuity health care, designing an effective clinical note template can be beneficial to both document patient care and clarify how telemedicine is used. We characterized documented interactions via a standardized note template between bedside intensive care unit (ICU) providers and teleintensivists in 2 Veterans Health Administration ICU telemedicine support centers. All ICUs linked to support centers and providing care from October 2012 through September 2014 were considered. Interactions were assessed based on initiation site, bedside initiator, contact type, and patient care change. Of 14 511 ICU admissions with teleintensivist access, teleintensivist interaction was documented in 21.6% (N = 3136). In particular, contacts were primarily initiated by bedside staff (74.4%), use increased over time, and of contacts resulting in changes in patient care, most were initiated by a bedside nurse (84.3%). Given this variation, future research necessitates inclusion of utilization in evaluation of Tele-ICU and patient outcomes.

Manometry Optimized Positive Expiratory Pressure (MOPEP) in Excessive Dynamic Airway Collapse (EDAC)

BACKGROUND

Positive expiratory pressure(PEP) breathing modalities are commonly prescribed in obstructive lung diseases, however practical methods of airway pressures(AP) quantification for therapeutic efficacy are lacking. Excessive dynamic airway collapse(EDAC) is characterized by expiratory central airway collapse leading to dyspnea and poor quality of life(QoL), with limited therapeutic options.

PURPOSE

To measure AP and exertional dyspnea in EDAC patients during normal breathing and with use of pursed-lip breathing(PLB), nasal PEP device(nPEP), and oral-PEP valve(oPEP) during rest and exercise using an Esophageal Manometer.

METHODS

EDAC patients exercised on a bicycle ergometer sequentially using normal breathing, PLB, nPEP, and oPEP for five-minute intervals. AP's were measured by continuous topographic upper airway manometry. Pre- and post-exercise BORG dyspnea scores were recorded and QoL measured with the St. George's respiratory questionnaire(SGRQ-C). The most effective and patient-preferred PEP modality was prescribed for daily activities and SGRQ-C repeated after one week.

RESULTS

Three women with symptomatic EDAC participated. Expiratory laryngopharyngeal AP's during exercise with normal breathing, PLB, nPEP and oPEP in patient-1 were 1.7, 14, 4.5, and 7.3 mmHg, in patient-2; 2.3, 8, 8.3, and 12 mmHg, and in patient-3; 1, 15, unobtainable, and 9 mmHg, respectively. Maximal reduction in BORG scores occurred with PLB in patient 1 and with oPEP in patients 2 and 3. After 1 week mean SGRQ-C scores declined by 17-points.

CONCLUSIONS

Upper airway manometry directly measures laryngopharyngeal pressures during rest and exercise and can be used to select and optimize PEP breathing techniques to improve respiratory symptoms in EDAC patients.

Reliable adherence to a COPD care bundle mitigates system-level failures and reduces COPD readmissions: a system redesign using improvement science

BACKGROUND

Readmissions of chronic obstructive pulmonary disease (COPD) have devastating effects on patient quality-of-life, disease progression and healthcare cost. Effective interventions to reduce COPD readmissions are needed.

OBJECTIVES

Reduce 30-day all-cause readmissions by (1) creating a COPD care bundle that addresses care delivery failures, (2) using improvement science to achieve 90% bundle adherence.

SETTING

An 800-bed academic hospital in Ohio, USA. The COPD 30-day all-cause readmission rate was 22.7% from August 2013 to September 2015.

METHOD

We performed a cross-sectional study of COPD 30-day readmissions from October 2014 to March 2015 to identify care delivery failures. We interviewed readmitted patients with COPD to identify their needs after discharge. A multidisciplinary team created a care bundle designed to mitigate system failures. Using a quasi-experimental study and 'Model for Improvement', we redesigned care delivery to improve bundle adherence. We used statistical process control charts to analyse bundle adherence and all-cause 30-day readmissions.

RESULTS

Cross-sectional review of the index (first-time) admissions revealed COPD was the most common readmission diagnosis and identified 42 system-level failures. The most prevalent failures were deficient inhaler regimen at discharge, late or non-existent follow-up appointments, and suboptimal discharge instructions. Patient interviews revealed confusing discharge instructions, especially regarding inhaler use. The COPD care-bundle components were: (1) appropriate inhaler regimen, (2) 30-day inhaler supply, (3) inhaler education on the device available postdischarge, (4) follow-up within 15 days (5) standardised patient-centred discharge instructions. The adherence to completing bundle components reached 90% in 5.5 months and was sustained. The COPD 30-day readmission rate decreased from 22.7% to 14.7%. Patients receiving all bundle components had a readmission rate of 10.9%. As a balancing measure for the targeted reduction in readmission rate, we assessed length of stay, which did not change (4.8 days before vs 4.6 days after; p=0.45).

CONCLUSION

System-level failures and unmet patient needs are modifiable risks for readmissions. Development and reliable implementation of a COPD care bundle that mitigates these failures reduced COPD readmissions.

A Randomized Trial of Long-Term Oxygen for COPD with Moderate Desaturation

BACKGROUND

Long-term treatment with supplemental oxygen has unknown efficacy in patients with stable chronic obstructive pulmonary disease (COPD) and resting or exercise-induced moderate desaturation.

METHODS

We originally designed the trial to test whether long-term treatment with supplemental oxygen would result in a longer time to death than no use of supplemental oxygen among patients who had stable COPD with moderate resting desaturation (oxyhemoglobin saturation as measured by pulse oximetry [Spo₂], 89 to 93%). After 7 months and the randomization of 34 patients, the trial was redesigned to also include patients who had stable COPD with moderate exercise-induced desaturation (during the 6-minute walk test, Spo₂ ≥80% for ≥5 minutes and <90% for ≥10 seconds) and to incorporate the time to the first hospitalization for any cause into the new composite primary outcome. Patients were randomly assigned, in a 1:1 ratio, to receive long-term supplemental oxygen (supplemental-oxygen group) or no long-term supplemental oxygen (no-supplemental-oxygen group). In the supplemental-oxygen group, patients with resting desaturation were prescribed 24-hour oxygen, and those with desaturation only during exercise were prescribed oxygen during exercise and sleep. The trial-group assignment was not masked.

RESULTS

A total of 738 patients at 42 centers were followed for 1 to 6 years. In a time-to-event analysis, we found no significant difference between the supplemental-oxygen group and the no-supplemental-oxygen group in the time to death or first hospitalization (hazard ratio, 0.94; 95% confidence interval [CI], 0.79 to 1.12; P=0.52), nor in the rates of all hospitalizations (rate ratio, 1.01; 95% CI, 0.91 to 1.13), COPD exacerbations (rate ratio, 1.08; 95% CI, 0.98 to 1.19), and COPD-related hospitalizations (rate ratio, 0.99; 95% CI, 0.83 to 1.17). We found no consistent between-group differences in measures of quality of life, lung function, and the distance walked in 6 minutes.

CONCLUSIONS

In patients with stable COPD and resting or exercise-induced moderate desaturation, the prescription of long-term supplemental oxygen did not result in a longer time to death or first hospitalization than no long-term supplemental oxygen, nor did it provide sustained benefit with regard to any of the other measured outcomes. (Funded by the National Heart, Lung, and Blood Institute and the Centers for Medicare and Medicaid Services; LOTT ClinicalTrials.gov number, NCT00692198 .).

A comparison of five surveys that identify individuals at risk for airflow obstruction and chronic obstructive pulmonary disease

BACKGROUND

The predictive characteristics of different screening surveys for the recognition of individuals at risk for airflow obstruction (AFO) have not been evaluated simultaneously in the same population.

PURPOSE

To compare five AFO/COPD screening questionnaires.

METHODS

383 individuals completed the Veterans Airflow Obstruction Screening Questionnaire, Personal Level Screener for COPD (VAFOSQ), the 11-Q COPD Screening Questionnaire (11-Q), the COPD Population Screener (COPD-PS) and the Lung Function Questionnaire (LFQ) and performed spirometry. AFO was defined as forced expiratory volume in one second divided by the forced vital capacity (FEV₁/FVC) < 0.7, fixed ratio (FR) or FEV₁/FVC < lower limit of normal (LLN). The predictive characteristics of the five questionnaires were calculated and non-parametric receiver operating characteristic (ROC) curves estimated by logistic regression.

RESULTS

376 participants completed at least two of the questionnaires and performed technically acceptable spirometry. AFO was present in 102 (27.1%) and 150 (39.9%) based on LLN and FR, respectively. The number of individuals positively selected by the VAFOSQ was 227, PLS 128, 11-Q 236, COPD-PS 217, and LFQ 328. The area under the ROC curves for the questionnaires was between 0.60 and 0.66 (LLN) and 0.58 and 0.66 (FR).

CONCLUSIONS

Although these screening surveys have acceptable and similar predictive ability for the identification of AFO, their published thresholds lead to substantially different classification rates. The choice of an appropriate threshold for the identification of individuals with possible AFO/COPD should consider the underlying prevalence of AFO/COPD in the target population and the relative costs of misclassifying affected and unaffected cases.

CLINICAL TRIAL REGISTRATION

None.

PRIMARY SOURCE OF FUNDING

Veterans Health Administration.

Veterans Airflow Obstruction Screening Questionnaire: A Survey to Identify Veterans with Airflow Obstruction

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality within the Veterans Healthcare Administration (VHA) and is frequently under-diagnosed. We developed the Veterans Airflow Screening Questionnaire (VAFOSQ) to improve the identification of Veterans with airflow obstruction (AFO), the most commonly used criterion for the diagnosis of COPD.We created an initial survey with 78 variables that have been associated with AFO. A total of 825 patients in 3 primary care clinics performed spirometry after bronchodilator administration and completed the initial survey. Best sets regression was used to build a model that predicted AFO optimally. A total of 195 of 825 (23.3%) patients had AFO and 7 items positively predicted AFO. When the questionnaire score was greater than 25, the VAFOSQ accurately identified AFO with an area under the receiver operating curve of 0.72. In a prospective validation cohort of 376 participants, the positive predictive value was 32% and negative predictive value 81%. The VAFOSQ is a reliable and valid instrument for the identification of veterans at risk for AFO who would benefit from further evaluation with spirometry and assessment for COPD. The VAFOSQ is straightforward to use and can be easily self-administered and self-scored enabling widespread application within the VHA.

Phosphodiesterase 4 inhibitors for the treatment of chronic obstructive pulmonary disease: a review of current and developing drugs

INTRODUCTION

Phosphodiesterase (PDE) inhibitors modulate lung inflammation and cause bronchodilation by increasing intracellular cyclic adenosine 3', 5'-monophosphate in airway smooth muscle and inflammatory cells. Roflumilast is the only approved PDE-4 inhibitor (PDE4I) for use in chronic obstructive pulmonary disease (COPD). Its beneficial clinical effects occur preferentially in patients with chronic bronchitis and frequent COPD exacerbations. Use of roflumilast as adjunctive or alternate therapy to other COPD medications reduces exacerbations and modestly improves lung function.

AREAS COVERED

This article reviews the current role of PDE4I in COPD treatment emphasizing roflumilast's clinical efficacy and adverse effects. This article also reviews developing PDE4Is in early clinical trials and in preclinical studies.

EXPERT OPINION

After decades of research in drug development, PDE4Is are a welcomed addition to the COPD therapeutic armamentarium. In its current clinical role, the salubrious clinical effects of PDE4I in reducing exacerbations and stabilizing the frequent exacerbator phenotype have to be cautiously balanced with numerous adverse effects. Developing drugs may provide similar or better clinical benefits while minimizing adverse effects by changing the mode of drug delivery to inhaled formulations, combining dual PDE isoenzyme inhibitors (PDE1/4I and PDE3/4I) and by forming hybrid molecules with other bronchodilators (muscarinic receptor antagonist/PDE4I and β2-agonist/PDE4I).

Update on ultra-long-acting β agonists in chronic obstructive pulmonary disease

INTRODUCTION

For the last two decades, long-acting β agonists (LABAs) have been a cornerstone in the management of chronic obstructive pulmonary disease (COPD). They relax airway smooth muscle and augment expiratory airflow, which reduces hyperinflation and improves dyspnea, functional capacity and quality of life. In recent years, Indacaterol, a LABA with an ultra-long duration of action (ultra-LABA), which only requires once-daily dosing, was approved by the FDA. The clinical efficacy of indacaterol is comparable, and, in some aspects better, than the currently available LABAs.

AREAS COVERED

This article reviews the pharmacological properties, clinical efficacy, safety and potential role of the ultra-LABAs in COPD management.

EXPERT OPINION

Ultra-LABAs are effective bronchodilators with a prolonged duration of action. By decreasing dosing frequency, ultra-LABAs potentially may improve respiratory medication adherence, which is associated with better survival and less healthcare utilization. In addition to their salubrious benefits, β agonists may produce untoward effects. Increased mortality and hospitalizations among patients with left ventricular heart failure, who were treated with β agonists, has caused concern about their use in patients with COPD and heart disease. Further experience and testing will determine the optimal role of ultra-LABAs in the management of COPD.

Provider recognition and response to echocardiographic findings indicating pulmonary hypertension in the Veterans affairs medical center population

PH occurs alone or in association with many disorders. Many patients with transthoracic echocardiography (TTE) findings suggesting PH never receive additional evaluation. Patient characteristics and echocardiographic data associated with increased recognition of PH have not been fully evaluated. We evaluated TTE reports at the Cincinnati Veterans Affairs Medical Center from 2005 to 2006 retrospectively for findings highly indicative of PH: Estimated systolic pulmonary artery pressure (sPAP) ≥40 mmHg, increased right atrial or right ventricular (RV) size, or reduced RV function. Only patients with left ventricular ejection fraction (LVEF) ≥50% and no known diagnosis of PH were included. Patient characteristics, TTE findings, provider recognition rates, and subsequent referral for additional evaluation were assessed. A total of 227 of 3,960 (5.7%) TTE reports revealed findings indicating possible PH. Providers acknowledged possible PH in 53 (23.4%) reports. Recognized PH was predicted by increased RV size (odds ratio (OR) = 5.07, P < 0.001), increased right atrial dimension (OR = 6.45, P < 0.001), decreased RV function (OR = 8.86, P < 0.001), and increased PAP (OR = 1.04 corresponding to each unit increase of PAP, P < 0.01). Patients with comorbid obstructive sleep apnea (OSA), interstitial lung disease, and dyspnea were also more likely to be recognized (OR = 3.63, P = 0.021; OR = 10.98, P = 0.004; OR = 2.39, P = 0.007, respectively). The 12-month mortality rate for recognized patients, 11.3% (7/53), was lower than for unrecognized patients, 25.3% (44/174; P = 0.03). Providers recognized less than one in four patients with echocardiographic evidence suggesting PH. Echocardiography reports revealing higher PAP and right heart dilation and dysfunction are associated with increased acknowledgement of possible PH.

Therapeutic paralysis in veterans with COPD

BACKGROUND

Chronic Obstructive Pulmonary Disease (COPD) is a common disorder of Veterans that causes significant morbidity and mortality. To measure Veterans' perceptions about COPD, the effect of COPD on their lives and health, and their needs for improved health, we performed a postal survey.

METHODS

3263 Veterans with a diagnosis of COPD who received care at the Cincinnati Veterans Affairs Medical Center in 2008 were stratified into quintiles by Veterans Health Administration-associated COPD healthcare cost and uniformly sampled.

RESULTS

493 of 1000 surveys (49%) were completed and returned. COPD had different effects on respondents in top and bottom quintiles (highest and lowest COPD-related cost) for: knowledge of COPD diagnosis (89% vs. 73%, p = 0.03); activities affected by breathing, including work (69% vs. 45%), recreation (85% vs. 62%), change in living arrangements (36% vs 16%), and increased need for help (54% vs. 25%) (p < 0.05 for all comparisons); emotional effect of respiratory symptoms, including depression (53% vs. 30%), fear (41% vs. 15%), and helplessness (49% vs. 24%) (p < 0.05 for all comparisons). 91% of Veterans were prescribed inhalers and one-quarter had difficulties using them. 25% of Veterans did nothing when they had symptoms of an exacerbation.

CONCLUSIONS

COPD has profound effects on Veterans' breathing related activities and generates many negative emotions. Primary care providers are critical in conveying the diagnosis of COPD and providing information about the disease and its management. Veterans with COPD adhere poorly to their medications, and report little instruction about COPD or its management.

Disproportionate utilization of healthcare resources among veterans with COPD: a retrospective analysis of factors associated with COPD healthcare cost

Background

COPD is a significant cause of morbidity and mortality in the Veterans Health Administration (VHA). To determine the clinical factors associated with the cost of COPD management, we analyzed the relationship between clinical characteristics and COPD healthcare costs at the Cincinnati VAMC.

Methods

We queried the VHA Decision Support System for patients diagnosed with COPD at the Cincinnati VAMC and calculated their VHA COPD-related encounters and costs in FY2008. Patients were ranked by COPD-related cost. We determined the detailed clinical characteristics of patients selected by modified systematic sampling and performed univariate and multivariable ordinary linear regression analysis to determine factors associated with cost.

Results

3263 Veterans had 11,869 encounters with a primary or secondary diagnosis of COPD: 10,032 clinic visits, 505 emergency department (ED) visits, and 1,332 hospitalizations and incurred a total COPD-related healthcare cost of $21.4 M: $2.4 M clinic visits, $0.21 M ED visits, and $18.7 M hospitalizations and $0.89 M for COPD-related prescription costs. When the patients were ranked by VHA healthcare costs, the top 20% of patients accounted for 86% of the total costs and 57% of the total encounters with a primary or secondary diagnosis code of COPD and 90% of the total costs and 75% of the total encounters with a primary diagnosis code of COPD. The clinical characteristics and VHA healthcare costs of 840 of the 3263 unique individuals with COPD were analyzed to determine those characteristics associated with increased COPD-related costs. Univariate analysis showed significant associations with 24 clinical variables; the 4 most highly associated factors were nursing home residence, total hospital admissions, use of oral corticosteroids, and supplemental oxygen (p < 0.001 for all). In multivariate analysis, total number of admissions (p < 0.001), management by a pulmonologist (p < 0.001), number of clinic visits (p < 0.001), use of short acting anticholinergic (p = 0.001), forced expiratory volume in 1 second (FEV1) (p = 0.011), number of prescriptions (p = 0.011), body mass index (BMI) (p = 0.025), and use of inhaled corticosteroid (p = 0.043) were associated with COPD management cost.

Conclusion

The total number of admissions, clinic visits, physiologic impairment, BMI, number of medications, and type of provider are strongly associated with the total cost of COPD management. These factors may be used to focus COPD management toward patients with the potential for high utilization of healthcare resources.

Efficacy and safety of eco-friendly inhalers: focus on combination ipratropium bromide and albuterol in chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality and its treatment is critical to improve quality of life, reduce symptoms, and diminish the frequency of COPD exacerbations. Due to the harmful environmental effects of pressurized metered-dose inhalers (pMDIs) containing chlorofluorocarbons (CFCs), newer systems for delivering respiratory medications have been developed.

Methods

A search of the literature in the PubMed database was undertaken using the keywords “COPD,” “albuterol,” “ipratropium bromide,” and “Respimat® Soft Mist Inhaler™”; pertinent references within the identified citations were included. The environmental effect of CFC-pMDIs, the invention of the Respimat® Soft Mist Inhaler™ (SMI) (Boehringer Ingelheim, Ingelheim, Germany), and its use to deliver the combination of albuterol and ipratropium bromide for the treatment of COPD were reviewed.

Results

The adverse environmental effects of CFC-pMDIs stimulated the invention of novel delivery systems including the Respimat SMI. This review presents its development, internal mechanism, and use to deliver the combination of albuterol and ipratropium bromide.

Conclusion

CFC-pMDIs contributed to the depletion of the ozone layer and the surge in disorders caused by harmful ultraviolet B radiation. The banning of CFCs spurred the development of novel delivery systems for respiratory medications. The Respimat SMI is an innovative device that produces a vapor of inhalable droplets with reduced velocity and prolonged aerosol duration that enhance deposition within the lower airway and is associated with improved patient satisfaction. Clinical trials have demonstrated that the Respimat SMI can achieve effects equivalent to pMDIs but with lower medication doses. The long-term safety and efficacy remain to be determined. The Respimat SMI delivery device is a novel, efficient, and well-received system for the delivery of aerosolized albuterol and ipratropium bromide to patients with COPD; however, the presence of longer-acting, less frequently dosed respiratory medications provide patients and providers with other therapeutic options.

Diagnosis of COPD and clinical course in patients with unrecognized airflow limitation

Chronic obstructive pulmonary disease (COPD) is frequently under-recognized and underdiagnosed. To determine the natural history of recognized and unrecognized COPD, we studied the rate of diagnosis, health care utilization, and mortality in patients with airflow limitation (AFL). Three hundred forty-seven outpatients at the Cincinnati Veterans Administration Medical Center performed spirometry and completed a respiratory questionnaire. Patients were followed for a minimum of 30 months and medical records were reviewed for COPD diagnosis, mortality, respiratory-related health care utilization, comorbidities, and respiratory medications. Three hundred twenty-five of 347 (94%) patients performed technically adequate spirometry and completed questionnaires. When AFL was defined by fixed ratio (FR, forced expiratory volume in 1 second [FEV(1)]/forced vital capacity [FVC] < 0.7), patients with AFL and a diagnosis of COPD had a higher annual mortality rate (7.1% ± 2% versus 2.4% ± 0.8%, P = 0.01), more hospitalizations per year (0.2 ± 0.06 versus 0.04 ± 0.01, P < 0.001 mean ± standard error of the mean), increased respiratory symptoms (12.0 ± 0.9 versus 7.2 ± 0.6, P < 0.0001), and higher Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage compared with undiagnosed patients. Ninety-two of 137 patients with AFL (67%) had unrecognized AFL; 16 (17%) of the 92 were subsequently diagnosed. When AFL was defined by the lower limit of normal (LLN, FEV(1)/FVC < LLN), 67 of 103 patients (65%) had unrecognized AFL; 12 (18%) of the 67 were subsequently diagnosed. Patients with AFL defined by FR who were subsequently diagnosed had more emergency department visits per year (0.33 ± 0.11 versus 0.11 ± 0.05, P = 0.009), increased respiratory symptoms (10.2 ± 1.6 versus 6.5 ± 0.7, P < 0.05), and higher GOLD stage, but similar mortality and hospitalizations compared with the persistently undiagnosed patients. The annual rate of documented COPD diagnosis was 7% for both FR and LLN definitions. Patients with AFL and a diagnosis of COPD have more severe disease, higher health care utilization, and mortality than undiagnosed patients. The annual rate of COPD diagnosis is 7% among individuals with unrecognized AFL. Worse AFL, increased respiratory symptoms, and ED visits are associated with a subsequent COPD diagnosis in individuals with unrecognized AFL.

Patient reported determinants of health: a qualitative analysis of veterans with chronic obstructive pulmonary disease

Although COPD is a common disorder of veterans who receive care from the Veterans Healthcare Administration (VHA), the perceptions of veterans with COPD about their disease, its effects on their lives, and their interactions with the VHA have not been determined. Utilizing qualitative methodology, we conducted focus groups of veterans with COPD at the Cincinnati VA Medical Center. Participants were selected by systematic sampling from the top quintile of veterans stratified by the cost of healthcare utilization related to a primary diagnosis of COPD and grouped by age and use of supplemental oxygen. All 42 participants were male and had a mean age of 65 years. Analysis of the focus group transcripts demonstrated five major themes: 1) Physical and Functional Limitations: work and employment constraints, recreation restrictions, limits on activities of daily living, reduced sexuality, concerns about housing and finances, and physical symptoms; 2) Restricted Social Interactions/Altered Social Networks: altered relationships with friends and family and reliance upon family and care givers; 3) Emotional Effects: reduced self-worth, vulnerability, depression, perseverance and adaptation, hopelessness, fear, pride, and lack of control; 4) Limitations in the Understanding of COPD: unawareness of diagnosis, triggers and reaction to disease manifestations, COPD management; and 5) Complex Healthcare Interactions. COPD pervasively and extensively affects all aspects of veterans' lives and causes significant consequences for their care and management.

Treatment of idiopathic pulmonary fibrosis with losartan: a pilot project

BACKGROUND

Idiopathic pulmonary fibrosis is a progressive interstitial lung disease with no current effective therapies. Treatment has focused on antifibrotic agents to stop proliferation of fibroblasts and collagen deposition in the lung. We present the first clinical trial data on the use of losartan, an antifibrotic agent, to treat idiopathic pulmonary fibrosis. The primary objective was to evaluate the effect of losartan on progression of idiopathic pulmonary fibrosis measured by the change in percentage of predicted forced vital capacity (%FVC) after 12 months. Secondary outcomes included the change in forced expiratory volume at 1 second, diffusing capacity of carbon monoxide, 6-minute walk test distance, and baseline/transition dyspnea index.

METHODS

Patients with idiopathic pulmonary fibrosis and a baseline %FVC of ≥50 % were treated with losartan 50 mg by mouth daily for 12 months. Pulmonary function testing, 6-minute walk, and breathlessness indices were measured every 3 months.

RESULTS

Twenty participants with idiopathic pulmonary fibrosis were enrolled and 17 patients were evaluable for response. Twelve patients had a stable or improved %FVC at study month 12. Similar findings were observed in secondary end-point measures, including 58, 71, and 65 % of patients with stable or improved forced expiratory volume at 1 second, diffusing capacity for carbon monoxide, and 6-minute walk test distance, respectively. No treatment-related adverse events that resulted in early study discontinuation were reported.

CONCLUSION

Losartan stabilized lung function in patients with idiopathic pulmonary fibrosis over 12 months. Losartan is a promising agent for the treatment of idiopathic pulmonary fibrosis and has a low toxicity profile.

A comprehensive care management program to prevent chronic obstructive pulmonary disease hospitalizations: a randomized, controlled trial

BACKGROUND

Improving a patient's ability to self-monitor and manage changes in chronic obstructive pulmonary disease (COPD) symptoms may improve outcomes.

OBJECTIVE

To determine the efficacy of a comprehensive care management program (CCMP) in reducing the risk for COPD hospitalization.

DESIGN

A randomized, controlled trial comparing CCMP with guideline-based usual care. (ClinicalTrials.gov registration number: NCT00395083) SETTING: 20 Veterans Affairs hospital-based outpatient clinics.

PARTICIPANTS

Patients hospitalized for COPD in the past year.

INTERVENTION

The CCMP included COPD education during 4 individual sessions and 1 group session, an action plan for identification and treatment of exacerbations, and scheduled proactive telephone calls for case management. Patients in both the intervention and usual care groups received a COPD informational booklet; their primary care providers received a copy of COPD guidelines and were advised to manage their patients according to these guidelines. Patients were randomly assigned, stratifying by site based on random, permuted blocks of variable size.

MEASUREMENTS

The primary outcome was time to first COPD hospitalization. Staff blinded to study group performed telephone-based assessment of COPD exacerbations and hospitalizations, and all hospitalizations were blindly adjudicated. Secondary outcomes included non-COPD health care use, all-cause mortality, health-related quality of life, patient satisfaction, disease knowledge, and self-efficacy.

RESULTS

Of the eligible patients, 209 were randomly assigned to the intervention group and 217 to the usual care group. Citing serious safety concerns, the data monitoring committee terminated the intervention before the trial's planned completion after 426 (44%) of the planned total of 960 patients were enrolled. Mean follow-up was 250 days. When the study was stopped, the 1-year cumulative incidence of COPD-related hospitalization was 27% in the intervention group and 24% in the usual care group (hazard ratio, 1.13 [95% CI, 0.70 to 1.80]; P= 0.62). There were 28 deaths from all causes in the intervention group versus 10 in the usual care group (hazard ratio, 3.00 [CI, 1.46 to 6.17]; P= 0.003). Cause could be assigned in 27 (71%) deaths. Deaths due to COPD accounted for the largest difference: 10 in the intervention group versus 3 in the usual care group (hazard ratio, 3.60 [CI, 0.99 to 13.08]; P= 0.053).

LIMITATIONS

Available data could not fully explain the excess mortality in the intervention group. Ability to assess the quality of the educational sessions provided by the case managers was limited.

CONCLUSION

A CCMP in patients with severe COPD had not decreased COPD-related hospitalizations when the trial was stopped prematurely. The CCMP was associated with unanticipated excess mortality, results that differ markedly from similar previous trials. A data monitoring committee should be considered in the design of clinical trials involving behavioral interventions.

Development of a Non-Invasive Dynamic Pulmonary Function Monitor

Characterizing the complexity of airflow limitation in diagnosing and assessing disease severity in asthma, COPD, cystic fibrosis, and other respiratory diseases can help guide clinicians toward the most appropriate treatments. Current technologies allow obstructive lung disease to be measured with about 5%−10% precision. A noninvasive dynamic pulmonary function monitor (DPFM) can quantify ventilation inhomogeneities, such as those originating in partially blocked or constricted small airways, with 1% precision if inert gas concentrations can be measured accurately and precisely over three to four decades of sensitivity. We have studied the precision and linearity of a commercially available mass spectrometer, sampling the gas exhaled by a mechanical lung analog, mimicking a multibreath inert gas washout measurement. The root mean square deviation of the inert gas concentration measured for each “breath,” compared to the expected value for a purely exponential decay, is found to be about 1.1% over three decades of concentration. The corresponding overall impairment, a specific measure of ventilation inhomogeneity, is found to be about 0.2%, which indicates that were inhomogeneities observed, the corresponding impairment could be measured with 1% precision.

NKG2D mediates NK cell hyperresponsiveness and influenza-induced pathologies in a mouse model of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is characterized by peribronchial and perivascular inflammation and largely irreversible airflow obstruction. Acute disease exacerbations, due frequently to viral infections, lead to enhanced disease symptoms and contribute to long-term progression of COPD pathology. Previously, we demonstrated that NK cells from cigarette smoke (CS)-exposed mice exhibit enhanced effector functions in response to stimulating cytokines or TLR ligands. In this article, we show that the activating receptor NKG2D is a key mediator for CS-stimulated NK cell hyperresponsiveness, because CS-exposed NKG2D-deficient mice (Klrk1(-/-)) did not exhibit enhanced effector functions as assessed by cytokine responsiveness. NK cell cytotoxicity against MHC class I-deficient targets was not affected in a COPD model. However, NK cells from CS-exposed mice exhibit greater cytotoxic activity toward cells that express the NKG2D ligand RAET1ε. We also demonstrate that NKG2D-deficient mice exhibit diminished airway damage and reduced inflammation in a model of viral COPD exacerbation, which do not affect viral clearance. Furthermore, adoptive transfer of NKG2D(+) NK cells into CS-exposed, influenza-infected NKG2D-deficient mice recapitulated the phenotypes observed in CS-exposed, influenza-infected wild-type mice. Our findings indicate that NKG2D stimulation during long-term CS exposure is a central pathway in the development of NK cell hyperresponsiveness and influenza-mediated exacerbations of COPD.

Clinical characteristics, comorbidities, and response to treatment of veterans with obstructive sleep apnea, Cincinnati Veterans Affairs Medical Center, 2005-2007

Introduction

Obstructive sleep apnea (OSA) is a common disorder that is associated with significant morbidity. Veterans may be at an elevated risk for OSA because of increased prevalence of factors associated with the development and progression of OSA. The objective of this study was to determine the clinical characteristics, comorbidities, polysomnographic findings, and response to treatment of veterans with OSA.

Methods

We performed a retrospective chart review of 596 patients undergoing polysomnography at the Cincinnati Veterans Affairs Medical Center from February 2005 through December 2007. We assessed potential correlations of clinical data with polysomnography findings and response to treatment.

Results

Polysomnography demonstrated OSA in 76% of patients; 30% had mild OSA, 23% moderate OSA, and 47% severe OSA. Increasing body mass index, neck circumference, Epworth Sleepiness Scale score, hypertension, congestive heart failure, and type 2 diabetes correlated with increasing OSA severity. Positive airway pressure treatment was initiated in 81% of veterans with OSA, but only 59% reported good adherence to this treatment method. Of the patients reporting good adherence, a greater proportion of those with severe OSA (27%) than with mild or moderate disease (0%-12%) reported an excellent response to treatment.

Conclusion

The prevalence of metabolic and cardiovascular comorbidities increased with increasing OSA severity. Only 59% of treated patients reported good adherence to treatment with positive airway pressure, and response to treatment correlated with OSA severity.

High prevalence of chronic obstructive pulmonary disease among veterans in the urban midwest

Although chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality within the Veterans Health care Administration, its prevalence and recognition are not known. We measured airflow limitation and diagnosed COPD at the Cincinnati Veteran's Administration Medical Center. Participants were 326 outpatients who performed spirometry and completed questionnaires. Health care-provider-diagnosis and self-diagnosis of COPD were compared with COPD defined by forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) < 0.7 (fixed ratio) and (FEV1/FVC)/lower limit of normal (LLN) < 1.0. COPD prevalence was 43% (95% confidence interval: 36.9, 48.1) by fixed ratio and 33% (95% confidence interval: 27.2, 36.8) by LLN. Eighteen percent of the patients had health care-provider-recorded and 23% had self-reported diagnoses of COPD. Positive predictive values for the diagnosis of COPD were 79% and 64% for healthcare providers versus 68% and 62% for patients; negative predictive values were 64% and 74% for healthcare providers versus 64% and 76% for patients (fixed ratio and LLN, respectively). COPD prevalence is higher among Cincinnati veterans than among general U.S. population. COPD is under-recognized by both health care providers and veterans.

Value of the PaO₂:FiO₂ ratio and Rapid Shallow Breathing Index in predicting successful extubation in hypoxemic respiratory failure

PURPOSE

We sought to determine the predictive value of the PaO₂:FiO₂ ratio (PFR), both independently and in combination with the standard Rapid Shallow Breathing Index (RSBI), for successful extubations in patients with primary hypoxemic respiratory failure (HRF).

MATERIALS AND METHODS

A retrospective chart review of 154 patients with HRF requiring mechanical ventilation for ≥24 hours was performed. The primary outcome was reintubation within 48 hours.

RESULTS

142 (92%) patients were successfully extubated. Pre-extubation PFR and RSBI values among reintubated and successfully extubated patients were similar. The areas under the curve of the receiver operating characteristic curves using RSBI and PFR were .5 and .62, respectively. A PFR < 200 or RSBI ≥ 70 when the PFR was ≥200 indicated a higher risk of reintubation, with .7 sensitivity and .56 specificity (area under the curve, .69), using a classification and regression tree model.

CONCLUSIONS

Neither the PFR independently nor the PFR in combination with the RSBI in a classification and regression tree model accurately predicted successful extubation in patients with HRF.

Critical care education during internal medicine residency: a national survey

BACKGROUND

Current training practices and teaching methods for critical care medicine education during internal medicine residency have not been well described. This study explored critical care medicine education practices and environments for internal medicine residents in the United States.

METHODS

A web-based survey recruited Pulmonary and Critical Care Medicine fellowship program directors involved with internal medicine residency programs at academic institutions in the United States.

RESULTS

Of 127 accredited Pulmonary and Critical Care Medicine programs in 2007, 63 (50%) responded. Demographics of the intensive care units varied widely in size (7-52 beds), monthly admissions (25-300 patients), and presence of a "night float" (22%) or an admissions "cap" (34%). All programs used bedside teaching, and the majority used informal sessions (91%) or didactic lectures (75%). More time was spent on resident teaching in larger (≥20 bed) medical intensive care units, on weekdays, in programs with a night-float system, and in programs that suspended residents' primary care clinic duties during their intensive care unit rotation.

CONCLUSIONS

Although similar teaching methods were used within a wide range of training environments, there is no standardized approach to critical care medicine education for internal medicine residents. Some survey responses indicated a correlation with additional teaching time.

Oxygen therapy for patients with COPD: current evidence and the long-term oxygen treatment trial

Long-term use of supplemental oxygen improves survival in patients with COPD and severe resting hypoxemia. However, the role of oxygen in symptomatic patients with COPD and more moderate hypoxemia at rest and desaturation with activity is unclear. The few long-term reports of supplemental oxygen in this group have been of small size and insufficient to demonstrate a survival benefit. Short-term trials have suggested beneficial effects other than survival in patients with COPD and moderate hypoxemia at rest. In addition, supplemental oxygen appeared to improve exercise performance in small short-term investigations of patients with COPD and moderate hypoxemia at rest and desaturation with exercise, but long-term trials evaluating patient-reported outcomes are lacking. This article reviews the evidence for long-term use of supplemental oxygen therapy and provides a rationale for the National Heart, Lung, and Blood Institute Long-term Oxygen Treatment Trial. The trial plans to enroll subjects with COPD with moderate hypoxemia at rest or desaturation with exercise and compare tailored oxygen therapy to no oxygen therapy.

Vitamin D deficiency and reduced lung function in connective tissue-associated interstitial lung diseases

BACKGROUND

Vitamin D is a steroid hormone with pleiotropic effects including immune system modulation, lung tissue remodeling, and bone health. Vitamin D deficiency has been implicated in the development of autoimmune diseases. We sought to evaluate the prevalence of vitamin D deficiency in a cohort of patients with interstitial lung disease (ILD) and hypothesized that vitamin D deficiency would be associated with an underlying connective tissue disease (CTD) and reduced lung function.

METHODS

Patients in the University of Cincinnati ILD Center database were evaluated for serum 25-hydroxyvitamin D levels as part of a standardized protocol. Regression analysis evaluated associations between 25-hydroxyvitamin D levels and other variables.

RESULTS

One hundred eighteen subjects were included (67 with CTD-ILD, 51 with other forms of ILD). The overall prevalence of vitamin D deficiency and insufficiency in the study population was 38% and 59%, respectively. Those with CTD-ILD were more likely to have vitamin D deficiency (52% vs 20%, P < .0001) and insufficiency (79% vs 31%, P < .0001) than other forms of ILD. Diminished FVC was associated with lower 25-hydroxyvitamin D(3) levels (P = .01). The association between vitamin D insufficiency and CTD-ILD persisted (OR, 11.8; P < .0001) after adjustment for potential confounders. Among subjects with CTD-ILD, reduced 25-hydroxyvitamin D(3) levels were strongly associated with reduced lung function (FVC, P = .015; diffusing capacity for carbon monoxide, P = .004).

CONCLUSIONS

There is a high prevalence of vitamin D deficiency in patients with ILD, particularly those with CTD-ILD, and it is associated with reduced lung function. Vitamin D may have a role in the pathogenesis of CTD-ILD.

Undifferentiated connective tissue disease-associated interstitial lung disease: changes in lung function

Undifferentiated connective tissue disease (UCTD) is a distinct clinical entity that may be accompanied by interstitial lung disease (ILD). The natural history of UCTD-ILD is unknown. We hypothesized that patients with UCTD-ILD would be more likely to have improvement in lung function than those with idiopathic pulmonary fibrosis (IPF) during longitudinal follow-up. We identified subjects enrolled in the UCSF ILD cohort study with a diagnosis of IPF or UCTD. The primary outcome compared the presence or absence of a > or = 5% increase in percent predicted forced vital capacity (FVC) in IPF and UCTD. Regression models were used to account for potential confounding variables. Ninety subjects were identified; 59 subjects (30 IPF, 29 UCTD) had longitudinal pulmonary function data for inclusion in the analysis. After accounting for baseline pulmonary function tests, treatment, and duration between studies, UCTD was associated with substantial improvement in FVC (odds ratio = 8.23, 95% confidence interval, 1.27-53.2; p = 0.03) during follow-up (median, 8 months) compared with IPF. Patients with UCTD-ILD are more likely to have improved pulmonary function during follow-up than those with IPF. These findings demonstrate the clinical importance of identifying UCTD in patients presenting with an "idiopathic" interstitial pneumonia.

Oxygen therapy in advanced COPD: in whom does it work?

Supplemental oxygen therapy is commonly used in patients with advanced chronic obstructive pulmonary disease (COPD) and severe hypoxemia at rest. Use of oxygen in these patients is justified by studies showing a mortality benefit. However, the use of oxygen in other patients with advanced COPD has not clearly been established. Long-term studies assessing not only mortality but also other outcomes that are important to patients and physicians such as dyspnea, health status, and exercise capacity are lacking. This article reviews the available studies of the use of supplemental oxygen in patients with less severe hypoxemia at rest during the day, hypoxemia occurring only at night, and hypoxemia occurring only with exercise. With the knowledge that studies in patients with advanced COPD and less severe hypoxemia are limited, recommendations are provided on oxygen use in these groups of patients.