More than half of the long-time smokers and former smokers who could pass the lung function test easily with breathing out forcibly may be suffering from COPD that was not detectable easily or in its early stages, warn researchers.
The early stages of chronic obstructive pulmonary disease (COPD) such as emphysema and chronic bronchitis cannot be detected with mere symptoms like breathlessness when active, constant cough with phlegm and frequent chest infection.
While the main reason for COPD is smoking, the researchers at National Jewish Health who studied the relationship between cigarette smoking and COPD diagnosis, say it could be misleading in the early stages.
They studied 8,872 people aged between 45 and 80, who had smoked at least ten cigarettes a day for ten years and some of them had a track record of smoking 30 to 50 cigarettes each day in the past.
Even after their lung test gave no clue, a thorough screening such as use of respiratory medication, physical function, respiratory symptoms and CT scans revealed that 55 percent of the participants who believed to be disease-free actually had some form of respiratory-related impairment.
Elizabeth Regan, lead researcher of the study, said: “Smokers who have ‘normal’ lung-function tests often have significant respiratory disease. Many of those smokers likely have the early stages of chronic obstructive pulmonary disease. We hope these findings will help debunk the myth of the healthy smoker and highlight the importance of smoking prevention.”
The NHS in UK shows that more than three million people there are living with the disease, of which only about 900,000 cases have been diagnosed, said the study that has been published in the journal JAMA Internal Medicine.
According to the WHO estimates a decade ago, 64 million people have COPD and 3 million people died of COPD. WHO predicts that COPD will become the third leading cause of death worldwide by 2030.
Chronic Obstructive Pulmonary Disease (COPD) is not one single disease but an umbrella term used to describe chronic lung diseases that cause limitations in lung airflow. The more familiar terms ‘chronic bronchitis’ and ’emphysema’ are no longer used, but are now included within the COPD diagnosis.
The most common symptoms of COPD are breathlessness, or a ‘need for air’, excessive sputum production, and a chronic cough. However, COPD is not just simply a “smoker’s cough”, but a under-diagnosed, life threatening lung disease that may progressively lead to death.
Main risk factors for COPD
- Tobacco smoking
- Indoor air pollution (such as biomass fuel used for cooking and heating)
- Outdoor air pollution
- Occupational dusts and chemicals (vapours, irritants, and fumes).