Millions of people who have signs of serious lung problems due to long-term tobacco exposure don’t get a clear diagnosis, a new study suggests.
The gap in diagnosis leads to potentially unmanaged conditions, which can later cause more serious health problems like lung infections, high blood pressure, heart issues and diabetes.
Researchers at the University of California, San Francisco (UCSF) found that people with 20 or more years of daily smoking history had serious symptoms that would usually point to chronic obstructive pulmonary disease (COPD), such as shortness of breath, excess phlegm or daily coughs. Yet, many weren’t properly diagnosed because their symptoms didn’t tick all of the boxes.
COPD is a common type of inflammatory lung disease that causes obstruction in one’s airways and makes it hard to breathe and carry out simple tasks. According to the American Lung Association, COPD is the sixth leading cause of death in the United States. There’s no cure for it. However, it is preventable and manageable with early diagnosis.
The condition is diagnosed using a simple breathing test called spirometry which tests lung function and measures how fast and how much air one can breathe in and out of the lungs.
Per National Institutes of Health data, about 12.5 million people reported a COPD diagnosis in 2020. Millions of people who have signs of low-quality lung function often don’t know they have the condition, so the actual number of people living with COPD is estimated to be much higher.
Though the number of cigarette smokers has dropped dramatically thanks to decades of anti-smoking awareness campaigns, an estimated 28.3 million adults still smoke cigarettes, according to the Centers for Disease Control and Prevention (CDC).
Additionally, an estimated 3.08 million middle school and high-school students use at least one tobacco product per day, including e-cigarette use. In fact, since the start of the COVID-19 pandemic, the CDC has reported a 50% climb in the number of people using e-cigarettes.
“This demonstrates a major gap in effective and compassionate care for tobacco-exposed persons and highlights the need for further study to find ways to help them,” William McKleroy, M.D., a pulmonologist at San Francisco Medical Center and one of the researchers said in a statement.
In the study, even though half of the participants had COPD-like symptoms, they were underdiagnosed or undertreated because they didn’t have noticeable airflow obstruction. Plus, their spirometry numbers looked normal.
However, during the study’s five or 10-year follow-up period, researchers found that many of the participants with normal spirometry numbers continued to have lung problems. In some cases, the symptoms and quality of life had worsened.
As a result, Prescott Woodruff, M.D., MPH, UCSF division chief of pulmonology and study author, noted that this might call for a broader definition of smoking-related chronic lung problems.
“These findings suggest that a large proportion of tobacco smoke-exposed persons without airflow obstruction have a persistent, symptomatic non-obstructive chronic airway disease that is distinct from COPD,” he said in a statement. “Although tobacco-exposed persons with preserved spirometry are currently categorized as having pre-COPD by the COPD guidelines, the data from the current study emphasize that the definition of smoking-related lung disease needs to be broadened so new treatments can be developed.”
In addition to this, the study findings also noted that Black participants were more likely to have lung problems with normal spirometry numbers compared to white participants. Black participants were also more likely to develop COPD in the long run.
“Even in persons with no respiratory symptoms and normal breathing tests, smoking continues to harm their lungs," James Kiley, Ph.D., director of the Division of Lung Diseases at the National Heart, Lung, and Blood Institute, said in a statement. “The study results highlight the importance of smoking cessation, underscore the need for regular follow-up of smokers with and without symptoms, and call for more research to treat respiratory symptoms due to smoking.”
