UI researcher, lab play key roles in study that finds COPD-like symptoms in some current, former smokers without diagnosis
In a finding that could lead to better treatment of smoking-related lung diseases, a group of scientists from institutions across the country – including the University of Iowa – is reporting that about half of current or former smokers have respiratory symptoms similar to COPD and an increased risk for exacerbations or “flare ups” of their symptoms despite normal lung function and a lack of COPD diagnosis. Many of these individuals show COPD-like symptoms, such as shortness of breath and difficulty exercising. They also have a high rate of respiratory medication use despite a lack of data from clinical trials about appropriate treatment of this particular patient population, the researchers note.
In addition to raising the question of whether the definition of COPD should be adjusted, the researchers say that the study highlights a large, understudied patient population who might nevertheless benefit from early treatment intervention. Their study, published May 11 in the New England Journal of Medicine, was funded by both the National Heart, Lung, and Blood Institute (NHLBI) and the Foundation for the National Institutes of Health (FNIH).
COPD, or chronic obstructive pulmonary disease, is the third leading cause of death in the United States. It is a progressive lung disease that makes it hard to breathe. Cigarette smoking is the leading cause of COPD. While researchers estimate that millions of Americans have COPD, many have the disease and do not know it. The condition is currently diagnosed using spirometry, a test that measures how much air you breathe out and how fast. Researchers have long observed that some current and former smokers appear to have respiratory symptoms associated with COPD—such as coughing and shortness of breath—despite having a normal spirometry test. However, the extent and clinical implications of this problem were unknown until now.
For the current study, the research team led by scientists at several institutions, including the University of California at San Francisco and the University of Michigan, conducted an observational study called SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study). It includes patient data collected between 2010 and 2015. The scientists examined respiratory symptoms and measured lung function with spirometry among 2,736 participants -- current or former smokers, aged between 40 and 80 years old, as well as controls who had never smoked. They found that respiratory symptoms were present in about half of the current or former smokers despite normal spirometry readings. Participants who had respiratory symptoms despite normal spirometry had an increased rate of exacerbations or “flare ups” of their symptoms. Using computed tomographic (CT) imaging scans of the lung, overseen by the SPIROMICS Radiology Center at the University of Iowa and analyzed at the VIDA Diagnostics Core Lab in the Bioventures Center of the University of Iowa, the researchers also found a high incidence of thickening of the airways, a sign of lung disease.
“These findings demonstrate that there is a large group of smokers who have COPD symptoms including associated flare-ups who have gone unclassified because of the reliance on pulmonary (lung) function tests. The study shows that quantitative CT scans can provide insights into underlying lung disease processes, and suggests that lung function tests should not necessarily serve as the only test for diagnosing COPD and guiding treatment,” says Eric Hoffman, PhD, director of the Advanced Pulmonary Physiomic Imaging Laboratory (APPIL) within the UI Health Care Department of Radiology, and home to the SPIROMICS Radiology Center.
Hoffman says the CT scans were important in this study because the scans were able to detect lung abnormalities even when standard pulmonary function tests were normal. Additionally, the scans helped differentiate between airway disease – the airway wall thickening – and emphysema. Hoffman says CT may provide a mechanism for following disease progression in addition to identifying targets for treatment. CT imaging may also be useful for assessing outcomes associated with interventions.
Melissa Shirk is a Radiology Technologist in the lab who has overseen all of the incoming data and she interfaced with all of the sites to keep the study on track. Mark Escher is the database manager who has overseen all of the data transfers to VIDA and then catalogued the results for transfer to the coordinating center in North Carolina.
About APPIL and VIDA:
The Advanced Pulmonary Physiomic Imaging Laboratory, within the Department of Radiology at the University of Iowa Carver College of Medicine directed by Dr. Eric Hoffman PhD, is an internationally recognized leader in the field quantitative lung imaging. The laboratory has served as the radiology center for a growing number of national and international multi-center studies for which lung imaging was a major component of the protocol. As such, more than 30,000 data sets have been sent to the laboratory for quality assessment and quantification. Hoffman and his research group has worked on lung imaging methods for nearly 40 years and he has led lung imaging research at the UI for 24 of those years. Standard pulmonary function testing has lumped many diseases into single entities and masked the presence of others. Imaging is allowing physicians to identify disease processes early and differentiate the processes, and thus is providing the hopes for better, earlier treatment of disease before the disease brings patients to the late stages of debilitation.
Through a $2 million grant from the National Institutes of Health and support by the University of Iowa, a state-of-the-art CT scanner built of Siemens known as the Somatom Force, has been installed within APPIL. This scanner enables researchers to generate CT images with up to 10 times lower x-ray dose, bringing the dose down to that of a pair of more traditional chest films while maintaining the high quality of image used in the study under discussion. With this scanner in place, the UI Laboratory is in the process of establishing a new set of protocols which will be implemented in future studies.
VIDA Diagnostics, Inc., is a company that evolved out of the University of Iowa and currently resides in the research park on the Oakdale Campus of the University of Iowa. VIDA provides software for the visualization and assessment of CT images of the lung and a core lab which provides the quality control over-sight necessary to assure that the measurement reliability. The company was founded by Eric Hoffman, PhD (Professor of Radiology and Biomedical Engineering) along with his colleagues Milan Sonka, PhD, (Electrical and Computer Engineering), Joseph Reinhardt, PhD (Biomedical Engineering) and Geoffrey McLennan, MD (Pulmonary Medicine), who passed away in 2010.
Disclosure: The founders remain shareholders within VIDA Diagnostics.
Story Source: Molly Rossiter, UI Health Care Marketing and Communications, 200 Hawkins Drive, Room W319 GH, Iowa City, Iowa 52242-1009
Media Contact: Jennifer Brown, UI Health Care Marketing and Communications, jennifer-l-brown@uiowa.edu