(HealthDay News) -- If all types of lung disease were combined, it would be the third-largest killer in the United States, the U.S. National Women's Health Information Center says.

It's important to recognize and treat symptoms of lung disease early. The American Lung Association offers this list of possible warning signs:

  • Having a persistent cough that lasts at least a month.
  • Having trouble catching your breath or finding it difficult to breathe.
  • Producing mucus continually for at least a month.
  • Making a noisy, wheezing sound when you breathe.
  • Coughing up blood.
  • Having persistent chest pain that lasts a month or more, particularly when you inhale or cough.