New research was presented at CHEST 2019, The Annual International Scientific Assembly of the American College of Chest Physicians, from October 19-23 in New Orleans. The features below highlight some of the studies presented at the conference.


Flu Vaccination & Pneumonia-Related Outcomes

With ongoing investigations and discussions regarding the role of influence vaccination in preventing influenza and resulting complications, like pneumonia, researchers conducted a study to determine the relationship between in-hospital influenza vaccination on 30-day outcomes among nearly 826,000 hospital admissions with a primary diagnosis of community-acquired pneumonia. Among cases, only 1.91% received in-hospital influenza vaccination. Among the 11.9% of readmissions within 30 days, 98.1% were for pneumonia. Readmissions had a significantly higher mortality rate than did index admissions (7.69% vs 3.32%). Nearly 490,000 hospital days, $1 billion in in-hospital costs, and $3.67 billion in in-hospital charges were associated with readmission. In-hospital influenza vaccination (hazard ratio, 0.821), advanced age, Medicare insurance, higher Charlson comorbidity score, atrial fibrillation, acute respiratory failure, and in-hospital oxygen use were associated with higher risks of readmission. The study authors conclude that the low rate of in-hospital influenza vaccination “indicates an underutilized service with significant implications on hospital readmission and mortality.”



Small Study Shows Improvements With 3D-Printed, Patient-Specific Airway Stents

The limited shapes and sizes of commercially available airway stents that often poorly fit patients with complex airways can result in numerous complications, including stent occlusion, granulation tissue formation, infection, biofilm, and migration. With the hypothesis that patient-specific (PS) stents may minimize these complications, improve quality of life, and reduce the need for repeated procedures, study investigators assessed outcomes following the placement of 13 3D-printed, PS silicone stents in four patients with underlying complex airway diseases who had multiple complications associated with commercially available airway stents. When compared with commercially available stents, 30.8% of PS stents were reported easier to load and 61.5% to have no difference in ease of loading into the rigid bronchoscope; 22.2% were reported easier and 77.8% to have no difference in difficulty to remove among the nine that required removal.  At 30 days, seven PS stents were associated with low-severity adverse events, a significant improvement over prior treatment with commercially available stents. Positive or no clinical change was associated with all PS stents placed, with a significantly longer mean duration between bronchoscopies (65.6 vs 36.6 days). PS stents had a lifespan of 300.2 days, compared with 124.0 days with commercially available stents.


Location-Specific Mortality Burden of CLRD

To determine any associations between chronic lower respiratory disease (CLRD) mortality burden and the geographic distribution of pulmonologists, researchers compared state-specific mapping of pulmonary fellowship programs and pulmonologists to the mortality burden due to CLRD in the United States in 2015. Among the 155,014 deaths attributed to CLRD in the US in 2015, the highest mortality rates were in Oklahoma (65.8%), West Virginia (64.6%), Kentucky (64.3%), and Arkansas (62.4%). Of 194 fellowship programs, 13 were located in these affected areas. High mortality rates were associated with fewer pulmonologists (<3) per 100,000 population when compared with states with lower disease-specific mortality rates, like New York and Massachusetts (5-10/100,000 population). In 2014, the rate of adults who had not seen a general practitioner in 12 months ranged from 15.9% in Vermont to 48.1% in Montana. Six of 9 states with the poorest healthcare usage were among those with the highest age-adjusted mortality. The study authors suggest their findings demonstrate the need for more pulmonologists in the US.


Bronchodilator Testing to Identify COPD, Asthma & ACOS

Previous studies indicate that spirometry bronchodilator (BD) testing has not regularly been used to diagnose COPD. Researchers sought to find the role BD testing plays in avoiding overdiagnosis ofCOPD and in identifying patients who could potentially benefit from a similar diagnosis, such as asthma or asthma-COPD overlap syndrome (ACOS). Analysis found that 39% of participants may have been overdiagnosed with COPD.Among participants with a pre-BD FEV1/FVC of less than 0.7, 61% had post-BD FEV1/FVC of less than 0.7, confirming irreversible airway obstruction. Among this 61%, 3.1% had asthma history and BD reversibility (BDR), 4.2% had asthma history and blood eosinophilia, and 0.7% had FEV1 change of 400 ml or greater and blood eosinophilia, making ACOS more likely than COPD alone in these subjects.  Among the other 39%, 9.8% had BDR alone, among whom 42% had BDR and eosinophilia, making asthma more likely. The study authors suggest that routine use of post-BD spirometry values will help prevent overdiagnosis of COPD and help physicians identify patients who may have ACOS and asthma.


Impact of 30-Day Readmission in Patients With Acute COPD Exacerbation

Research indicates that COPD is the third leading cause of death in the US and affects 16 million individuals. To determine the rate of 30-day readmission after hospitalization for COPD exacerbation, along with the effect on mortality and use of healthcare recourses, researchers examined the National Readmission Database 2016. They retrospectively identified participants who had been diagnosed with acute COPD exacerbation, among whom the average age was 68 and 58% were female. The 30-day all-cause and COPD-specific readmission rates were 16.3and 5.4%, respectively, with in-hospital mortality rates increased significantly during readmission (1.1% vs 3.8%). Lengths of stays upon readmission was cumulatively 458,677 days for all-causes and 132,026 days for COPD.. All-cause readmissions were associated with costs of $0.97 billion and charges of $4.0 billion, while COPD-specific readmissions were associated with costs of $253 million and charges of $1 billion. “Reducing the 30-day readmission rates in this setting has the unique potential to reduce both the mortality and healthcare expenditures associated with COPD,” write the study authors.