Sleep apnea what age group is it most commonly found in?

Hi I am doing some research for a class i am taking and i have a project on sleep apnea and i need some help finding out some info on this topic.

I just found out that I have a enlarged heart with sleep apnea what are my chance ?

I just found out i had a enlarged heart 2 yrs ago and now it is worse . I am stressed out so much . I also have a sleep apena and quit breathing at night. my heart does not ever slow down. What can be done to help this problem?