I have a breathing machine and use it at night for sleep apnea . does using it cause emphysema?

Sleep apnea: Not unless u use agents that irritate lungs such as smoking.

No: Emphysema is a chronic condition (doesnt happen overnight or a couple of months) of the lung that is rare in people your age. Also the CPAP machine helps prevent long term pulmonary problems and is very rare that it can cause them. If you are having unexplained lung problems, its time to be seen by a physician. Your primary is good start or even a pulmonologist.