damage to the fragile connections between alveoli.

 significant lung damage has occurred, and they usually worsen over time, particularly if smoking exposure continues. For chronic bronchitis, the main symptom is a daily cough and mucus (sputum) production at least three months a year for two consecutive years.

Other signs and symptoms of COPD may include:

• Shortness of breath, especially during physical activities
• Wheezing
• Chest tightness
• Having to clear your throat first thing in the morning, due to excess mucus in your lungs
• A chronic cough that may produce mucus (sputum) that may be clear, white, yellow or greenish
• Blueness of the lips or fingernail beds (cyanosis)
• Frequent respiratory infections
• Lack of energy
• Unintended weight loss (in later stages)
• Swelling in ankles, feet or legs

People with COPD are also likely to experience episodes called exacerbations, during which their symptoms become worse than usual day-to-day variation and persist for at least several days.