With you not having smoked for 20 years, it is quite unlikely that your current dry cough is a sign of emphysema. However, the onset of persistent cough, dry or otherwise, at any age is a reasonable cause for concern. The standard definition of chronic cough is one that lasts longer than 3 months. If your cough has lasted longer than that, you should have it investigated to be sure that it is not a sign of a disease other than emphysema. The odds of this cough being a benign event are in your favor, you made that important decision to quit smoking 20 years ago.
You would do well to consult with a lung specialist, also known as a pulmonologist, to try to get a definitive answer about the likely cause of this cough; the most common causes being asthma/bronchitis, gastroesophageal reflux disease (GERD) and postnasal drip. You should minimally have a chest x-ray and maybe even a CT scan of your lungs, along with pulmonary function tests (PFTs) to, hopefully, put the issue of emphysema to rest.
Your family history of emphysema is of concern. There is a “Family Clustering” of emphysema, an increased but as yet not genetically confirmed vulnerability to developing emphysema chronic obstructive pulmonary disease (COPD) and another condition called alpha-1 antitrypsin deficiency, which is an inherited predisposition to emphysema; the “deficiency” being measurable by a blood test. Whatever other tests are performed, you should ask the pulmonologist about testing your blood for this disorder. Should you have this disorder, that information could be valuable to other members of your family, especially any children you may have.
Good luck.
Thank you. Your response is valuable to me. I will take the necessary precautions for myself and my children. I have a grown daughter with Asthma like symptoms that comes every winter and we live in Arizona. I think her and I are going to get tested for the alpha-1 antitrypsin deficiency. Thanks again for your detailed response. Susan