Although CF is still considered a "childhood disease" we have many members who were diagnosed late in life. Sometimes because the symptoms were similiar to other illnesses & sometimes because of the ignorance of the medical community.
There is no way to say what your outcome would be if diagnosed at this age. Gene mutations, care compliance, environment, attitude & luck all play a park. There are many of us that went on disability. Some because we just could work & care for ourselves any longer and others because they just physically could no longer work.
30% lung capacity is pretty low. Many people (depending on other factors also) start thinking of lung transplants around that level. My last PFT at an end of one of my hospital admissions in September had me at 30%. I havent done any lung function test recently.
I do suggest that you make sure any testing for CF is done at an accredited CF Center. IF you have a choice I would start with Genetic Testing to look for any gene mutations. Often the Sweat Test is done first, but there have been confirmed cases with some of our members where the sweat test showed negative or borderline numbers, but genetic testing confirmed CF.
If you have anymore ?? please ask. We are here to listen, inform & support you the best we can.