Researchers from National Jewish Health took a closer look at long-term smokers and found that most of the smokers who had passed a lung-function test, indicating no sign of lung disease, may actually have been left undiagnosed./p>
The study revealed a flaw in the widely used lung-function tests, leaving millions substantially underestimated. The research team evaluated 8,872 people between the ages of 45 and 80, who smoked a pack a day for 10 to 50 years. Half of the group passed a lung-function test, which measures how much air you can take into and blow out of your lungs, and how fast you can do it by blowing into a spirometer. When the group that passed the lung-function test was reevaluated with a CT scan, patients' physician abilities, use of respiratory medication, and respiratory symptoms, 55% of the reevaluated patients actually had respiratory problems. The research also indicates that it is likely that many of these participants have early-stage chronic obstructive pulmonary disease (COPD), an incurable and progressive disease of the lungs. COPD is the third leading cause of death in the U.S.
Early detection of COPD leads to an earlier treatment intervention, which could lessen the symptoms, slow progression and improve overall quality of life. The researchers hope to prove screening with CT scans should be routing in order to detect early stages of lung cancer and COPD.
With CT scans alone, researchers were able to see airway thickening or emphysema in 42% of the undiagnosed patients. 23% had a significant shortness of breath, and 15% could not walk 350 meters in 6 minutes, compared to the 4% of those who had never smoked.
The researchers hope that these findings will help debunk the myth of the healthy smoker and highlight the importance of smoking prevention and cessation to prevent lung disease and other long-term effects of smoking.