The under-reporting of the condition is being highlighted on World COPD Awareness Day.
Barely a quarter of people believed to be living with COPD are actually diagnosed with it.
The figures are being highlighted on World COPD Awareness Day, and the theme this year is "Breathing is Life - Act Earlier."
Symptoms for the lung disease include shortness of breath, wheezing and chest tightness.
Portlaoise's Denise Croke was 42 when she was diagnosed with COPD - she outlines what led to her seeking a diagnosis: