I have been diagnosed with the early signs of COPD is it safe to have a Breast Reduction?

It is less safe.  Your plastic surgeon will likely get pre-operative clearance exams with your pulmonologist and primary care physician and possibly cardiology.  With the information in those visits, your surgeon will be able to optimize your COPD pre-operatively and post-operatively.  He will also be able to have a more informed discussion about risks, benefits, and alternatives with you.  The final decision to move forward can only be made with you and your surgeon after informed consent.  It is possible, that your surgeon may advise that the surgery is too risky after reviewing your clearances and decline to offer surgery.  

Any medical condition requires evaluation and clearance from your primary physician to have a safe breast reduction. Obstructive pulmonary disease might not prevent a breast reduction if the condition is well managed.