Many previous definitions of COPD have emphasized the
terms “emphysema” and “chronic bronchitis,” which are
not included in the definition used in this or earlier GOLD
reports. Emphysema, or destruction of the gas-exchanging
surfaces of the lung (alveoli), is a pathological term that
is often (but incorrectly) used clinically and describes
only one of several structural abnormalities present in
patients with COPD