Chronic obstructive pulmonary disease (COPD) has been known to mankind for over 200 year. The disease was initially recognized with the use of the stethoscope and spirometer and spirometry still remains the most effective means of identification and assessment of the course of COPD and responses to therapy.
COPD is the fourth most common cause of death in the USA. Approximately 16 million adult Americans have COPD. It is on the rise as one of the top five killer diseases. By 2020 COPD is expected to become the third most common cause of death.
Over years of study it has emerged that COPD refers to airways obstruction over the long term and COPD includes:-
- chronic bronchitis
- chronic asthmatic bronchitis
Earliest references to COPD
It was in 1679 that Bonet described COPD as “voluminous lungs”. It was corroborated around a century later in 1769 by Morgagni. They described cases in which the lungs were “turgid”, particularly from air.
Baillie in 1789 published a series of illustrations of the emphysematous lung putting forth the pathology of the disease. Thus emphysema was known to be a part of COPD early one.
It was much later that chronic bronchitis got included in COPD. Badham in 1814 used the word catarrh to refer to the chronic cough and increased mucus secretion as symptoms of bronchiolitis and chronic bronchitis that could be part of COPD.
Laënnec described emphysema of the lungs in 1821 in his Treatise of diseases of the chest. He was the inventor of the stethoscope who wrote that emphysema lungs were excessively inflated that did not empty well. Laënnec went on to describe a combination of emphysema and chronic bronchitis.
It was in 1846 that John Hutchinson invented the spirometer. This was the key to diagnosing COPD. The spirometer is still used today for diagnosis and regular assessment regarding response to therapy in COPD. Hutchinson’s instrument only measured vital capacity. It was in 1947 that Tiffeneau and Pinelli added the concept of timed vital capacity as a measure of airflow.
Definition of COPD
The CIBA Guest Symposium in 1959 and the American Thoracic Society Committee on Diagnostic Standards in 1962 were the first to describe the definition of COPD.
- The American Thoracic Society defined chronic bronchitis in clinical terms including chronic cough lasting at least three months for at least two years.
- The American Thoracic Society defined emphysema as enlarged alveolar spaces and loss of alveolar walls.
William Briscoe was the first person who used the term COPD in discussion at the 9th Aspen Emphysema Conference in 1965.
Treatment of COPD
Earlier the only therapies for COPD were antibiotics for pneumonia, a mucus thinner called potassium iodide and bronchodilators like ephedrine, theophylline etc. There were in addition sedatives to deal with the side effects of ephedrine.
It was in 1960’s that isoproterenol – a selective beta 2 agonist was used. Corticosteroids were almost never used and oxygen was not advised at the time.
Over the last 5 decades there has been the advent of inhaled short acting beta 2 agonists like Salbutamol, long acting beta 2 agonists like Formoterol and Salmeterol.
There has also been the advent of antimuscarinic agents like tiotropium and ipratropium that took over initially used atropine.
Oxygen therapy and pulmonary rehabilitation also developed over the last half of the 20th century.