Chronic Obstructive Pulmonary Diseases:Journal of the COPD Foundation

Volume 11, Issue 2 - 2024 | Plain Language Summaries

Short summaries, in non-technical, simple language of articles published in the most recent issue of Chronic Obstructive Pulmonary Diseases: Journal of the COPD Foundation are provided here. Links to the full, published research article are provided with each summary. The Journal is indexed by PubMed, PubMed Central, Scopus and Web of Science.

All summaries for the current issue are listed below in the order of publication, scroll down.

Assessment of Obstructive Sleep Apnea Among Patients With Chronic

Obstructive Pulmonary Disease in Primary Care

Lucas M. Donovan, MD, MS; Thomas L. Keller, MD, MS; Nancy H. Stewart, DO, MS; Jennifer Wright, MD; Laura J. Spece, MD, MS; Kevin I. Duan, MD, MS; Aristotle Leonhard, MD; Brian N. Palen, MD; Martha E. Billings, MD, MS; David H. Au, MD, MS; Laura C. Feemster, MD, MS

Obstructive sleep apnea frequently reduces sleep quality in patients with chronic obstructive pulmonary disease (COPD). While treating obstructive sleep apnea can improve patients’ symptoms, most cases of obstructive sleep apnea are undiagnosed or untreated. The first step in diagnosing and managing obstructive sleep apnea typically begins in primary care with a review or assessment of symptoms or current treatment use.

To better understand obstructive sleep apnea assessment, we identified patients with COPD at 2 primary care practices from 2011−2013. We reviewed charts to record whether health care providers evaluated the patients for sleep apnea, either by documenting sleep apnea symptoms, treatments, or referrals to sleep medicine specialists. Among 641 patients with COPD, 23% (146) were checked for sleep apnea. Patients with known sleep apnea, higher body mass index, and prior visits with a pulmonary specialist were more likely to have sleep apnea assessed. Importantly, patients who identify as Black or African American had half the chance of being assessed for sleep apnea as their White peers.

Our findings highlight the need to better understand the impact of sleep apnea assessment on long-term outcomes or results and the need for efforts to improve equity in who is assessed for sleep apnea.

Health Status Progression Measured Using Weekly Telemonitoring of COPD Assessment Test Scores Over 1 Year and Its Association with COPD Exacerbations

Paul Jones, MD, PhD*; Toru Soutome, BPharm*; Taizo Matsuki, PhD*; Masahiro Shinoda, MD, PhD; Osamu Hataji, MD, PhD; Motohiko Miura, MD, PhD; Masaharu Kinoshita, MD; Akira Mizoo, MD; Kazunori Tobino, MD; Takanobu Nishi, MSc; Takeo Ishii, MD, PhD; Yoko Shibata, MD, PhD
*contributed equally

The COPD Assessment Test (CAT) is a questionnaire that measures the health status of individuals with COPD. In this study, Japanese participants with COPD aged 40 years or older used a telemedicine smartphone platform to remotely collect their CAT scores every week for one year. The change in CAT score was measured over time and participants were placed into 3 groups based on the change in their score: “improved,” “stable,” or “worsened.”

Throughout the study, 50% of participants showed evidence of worsening health status, 22% were stable, and 28% were improving. A worsening score was associated with a 13% increased risk of a moderate exacerbation or disease flare-up and a 22% increased risk of a severe exacerbation over the 1 year.

These results support the use of telemedicine for regular monitoring of CAT scores to help patients, physicians, and researchers identify patterns of changing health status. This may provide an opportunity for an earlier review of the effects of treatment, which may improve how the disease is managed and patients’ overall quality of life.

Respiratory Microbiome Profiles Associated With Distinct Inflammatory Phenotype and Clinical Indexes in Chronic Obstructive Pulmonary Disease

Tao Yu, MS; Yunru Chen, MS; Xiaoxia Ren, MD; Ting Yang, MD

Chronic obstructive pulmonary disease (COPD) is characterized by persistent respiratory symptoms and restricted airflow. This can cause airway and/or alveolar (the tiny air sacs in the lungs) abnormalities. We know that bacterial colonization (the presence of non-disease-causing bacteria) in the lungs of patients with COPD is an important factor contributing to chronic airway inflammation. However, the reasons for this are unclear.

In this study, we divided patients into 2 clusters based on the types of microorganisms in their sputum (the mucus coughed up from the lungs). We found that a cluster of patients had a smaller amount of 2 types of bacteria—Prevotella and Fusobacterium—in their sputum and a larger amount of the bacteria Bacteroides. This cluster of patients had worse scores on the COPD Assessment Test which measures the impact COPD has on an individual’s life. This cluster of patients also had more inflammation from neutrophils, a kind of white blood cell.

This study indicates that there is a correlation between changes in the bacteria in the lungs of patients with COPD and the severity of the disease.

A Plant-Centered Diet is Inversely Associated with Radiographic Emphysema: Findings from the CARDIA Lung Study

Mariah K. Jackson, MMN; Yuni Choi, PhD; Elliot Eisenberg, MD; Corrine Hanson, PhD; Ann Wang, MD; Jing Gennie Wang, MD; George R. Washko, MD; Samuel Ash, MD; Raul San Jose Estepar, PhD; Gabrielle Liu, MD; James M. Shikany, DrPH; Lyn M. Steffen, PhD; Robert Wharton, MD; Ravi Kalhan, MD; David R. Jacobs, Jr, PhD; Sonali Bose, MD, MPH

Chronic obstructive pulmonary disease (COPD), including emphysema, is a significant public health concern. Smokers are a high-risk population for emphysema with few prevention strategies other than quitting smoking. We studied young smokers (between 18−30 years old at enrollment) to see if those who ate a more nutritionally rich, plant-centered diet— including higher amounts of fruits, vegetables, and whole grains, and lower amounts of refined grains and red and processed meats—had a reduced risk of emphysema 25 years later.

Emphysema was the least common in those with the best diet. Even after accounting for the impact of smoking, eating a nutritionally rich, plant-centered diet throughout young and middle adulthood was related to a decreased risk of emphysema developing later in life. Promoting diet changes to include more fruits, vegetables, and whole grains could be an additional strategy for emphysema prevention in a high-risk smoking population.

Effect of Physical Position on Peak Inspiratory Flow in Stable COPD: An Observational Study

Roy A. Pleasants, PharmD; Ashley G. Henderson, MD; Valentina Bayer, PhD; Asif Shaikh, MD; M. Bradley Drummond, MD, MS

Little is known about the impact different postures used by patients (sitting, standing, etc.) can have on the delivery of inhaled medicines into the lungs. A strong inhalation (breathing in deeply) increases the amount of inhaled drug reaching the lungs when using a dry powder inhaler. It seems natural to assume that less medicine would reach the lungs when patients are using a dry powder inhaler while lying down, as in a hospital bed.

We conducted a study looking at factors affecting a COPD patient’s ability to achieve the maximum amount of air that can be inhaled in one deep breath, called peak inspiratory flow. As part of this peak inspiratory flow study, we also compared the effects of sitting, standing, and the semi-upright position (lying at 45o). We used an instrument called the INCheck®DIAL to measure patients’ ability to reach their peak inspiratory flow.

Seventy-six patients completed this portion of the study. Nearly one-half had a worsening peak inspiratory flow of greater than 10% when comparing using the inhaler in a semi-upright position versus using it while standing. A small number of individuals showed declines of greater than 20%. Differences were not as large when comparing sitting to standing.

The effect of posture on peak inspiratory flow in patients using dry powder inhalers should be considered. Standing is the most ideal posture when using dry powder inhalers. However, sitting may be necessary in some patients and/or settings.

The Neutrophil-to-Lymphocyte Ratio as a Predictor of Acute Exacerbations Among Patients with COPD in Uganda

Patricia Alupo, MBChB, MMed; Winceslaus Katagira, MBChB, MMed; David Mukunya, MBChB, PhD; Paul Okimat, MSc; Vickram Tejwani, MD; Alex Kayongo, PhD; Joanitah Nalunjogi, MSc; Nicole M. Robertson, MD; Rupert Jones, MD, PhD; John R. Hurst, PhD; Bruce Kirenga, MBChB, MMed, PhD* Trishul Siddharthan, MD*
*Joint senior authorship

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death globally with 90% of COPD-related deaths occurring in low- and middle-income countries like Uganda. The most widely known risk factor for COPD is tobacco smoking, but in low- and middle-income countries, biomass (wood, straw, dung, etc.) smoke and infectious diseases like HIV are more common risk factors. This means that the disease process may differ from the tobacco type.

Acute exacerbations (disease flare-ups ) of COPD are a common cause of hospitalization and contribute to death among COPD patients globally. This study aimed to evaluate if an easily obtained marker in the blood, called the neutrophil-to-lymphocyte ratio could be used to predict the risk of having an exacerbation or flare-up among this COPD patient population, whose risk factors are different from the COPD patients in high-income countries.

Among 312 participants with COPD, those who experienced an exacerbation had a higher neutrophil-to-lymphocyte ratio at baseline compared to those who did not experience one. These findings suggest that the neutrophil-to-lymphocyte ratio could be used as a risk predictor for hospital admissions related to COPD exacerbations in low- and middle-income countries.

Post Hoc Analysis of Lung Function Improvement and Patient-Reported Outcomes With Revefenacin in Adults With Moderate-to-Very Severe COPD and Comorbid Anxiety or Depression

Abebaw M. Yohannes, PhD, MSc; Anand S. Iyer, MD, MSPH; Candice Clay, PhD; Lauren Cochran, PharmD; Xianyi Chen, MS; David A. Lombardi, PhD; Surya P. Bhatt, MD, MSPH

Chronic obstructive pulmonary disease (COPD) affects almost 400 million people worldwide and may lead to poor quality of life. People with COPD often suffer from anxiety and/or depression, which can worsen their health. Taking medications as prescribed (called adherence) is important when treating COPD and is often poor in people with anxiety and/or depression.

Revefenacin is a once-a-day drug approved for the treatment of COPD. In clinical trials, revefenacin improved lung function, with most people remaining adherent to the medication.

This study’s purpose was to determine the effect of revefenacin on lung function and quality of life in people with moderate-to-very severe COPD with self-reported anxiety and/or depression.

Lung function improved in people who received revefenacin versus placebo (a treatment containing no active medicine), regardless of whether anxiety and/or depression were present. Questionnaires that assessed the quality of life showed improvement in people who received revefenacin versus the placebo in all patients with the only exception of patients who self-reported depression only.

These findings support the use of revefenacin in people with COPD with anxiety and/or depression. Further work is needed to understand the relationship between respiratory and psychiatric disorders.

Effects of Dronabinol on Dyspnea and Quality of Life in Patients with COPD

Abdul H. Zaid, MBBS; Suman B. Thapamagar, MBBS; James D. Anholm, MD; Laura Weaver-Carnahan, RN, RRT; Lien Duong, PharmD; Lennard Specht, MD

Shortness of breath is often a debilitating symptom in patients with chronic obstructive pulmonary disease (COPD). Our small clinical study evaluated the effects of dronabinol, a synthetic tetrahydrocannabinol (THC), on breathlessness and exercise tolerance (the amount of exercise an individual can withstand before becoming over-exerted) in individuals with COPD. We thought that dronabinol, by acting on areas within the brain responsible for the perception or awareness of breathlessness, would reduce the intensity of such symptoms and thereby, improve exercise tolerance.

Participants received dronabinol for 6 weeks followed by a placebo (a treatment with no active medicine) for 6 weeks or vice versa with an intervening “wash out” period of 8−12 weeks. Investigators and participants remained blinded in other words, unaware of which study drug individuals were receiving at any time during the study. Using standardized scoring systems, the participants’ breathlessness, fatigue, functional status, and mood were assessed before and after dronabinol and placebo administration. Using a shuttle walk exercise test, the participants’ exercise capacity (the maximum amount of physical activity that an individual can maintain) was measured before and after receiving dronabinol and the placebo.

Contrary to what we thought would happen, dronabinol, when compared to a placebo, did not improve exercise capacity, breathlessness, fatigue, functional status, or mood in individuals with COPD in this small study. Larger randomized trials are needed to definitively assess the impact of dronabinol and related THC compounds in COPD patients.

Association Between Dietary Fiber Intake and Prevalence of Chronic Obstructive Pulmonary Disease in a Middle-Aged and Elderly Population: A Study Based on the National Health and Nutrition Examination Survey Database

Jun Jin, BS; Yuemei Bian, BS; Zhongyun Gu, BS; Maoen Lin, BS

Our study investigated how eating more dietary fiber relates to the occurrence of chronic obstructive pulmonary disease (COPD) in people over 40 years old.

We used data from the National Health and Nutrition Examination Survey and found that eating more dietary fiber was associated with a lower risk of COPD. This was especially true for men, middle-aged individuals, those with a body mass index of 30 or less, smokers, and people who drink alcohol. We also discovered that when people consumed at least 15.10 grams of dietary fiber each day, the risk of COPD decreased. Additionally, we found that white blood cell counts may play a role in how eating dietary fiber affects COPD risk.

Overall, our findings suggest that including more dietary fiber in your diet could help reduce the likelihood of developing COPD, especially for certain groups of people.

Variations in COPD Health Care Access and Outcomes: A Rapid Review

Julie A. Shatto, BSc; Michael K. Stickland, PhD; Lesley J. J. Soril, PhD

We conducted a review of research studies and reports to understand whether and how health care may differ for individuals with chronic obstructive pulmonary disease (COPD). The goal was to identify if there is inequity or unfairness in the way individuals with COPD access health care (e.g., take medications, see a doctor) and experience outcomes (e.g. hospital stays, death) related to their health or condition.

In our review, we included 35 articles, most being studies from Europe and the United States. The remaining articles were from Canada, Australia, and New Zealand. We found that for those with COPD, where they live and their socioeconomic status (a person’s standing in society based on their education, where they live, their occupation, their financial situation, and their access to resources) made a difference in their access to health care and health outcomes. Specifically, those living outside of large cities and of lower socioeconomic status had poor access to health care and outcomes such as an increased risk of death. Other factors, including an individual’s ethnicity, race, age, and sex, were at times associated with differences in health care access and outcomes. However, these findings were less consistent across the articles reviewed.

Broadly, large differences exist in health care access and outcomes for individuals with COPD. With this knowledge, we are more informed to make changes to ensure fair, high-quality health care and better health for people with COPD.