ALS, does anyone know if Prednisone can cause ALS, I have been on...

ALS, does anyone know if Prednisone can cause ALS, I have been on and off Pred. for years for my asthma and COPD, mostly the asthma attacks. I am on Oxygen 24/7. In the past 3 months I have been in the hosptial twice, for low oxygen levels, and severe asthma attacks, the first 2 night stay they had me on 160 mg every six hours. When I first went to the ER, I was unable to say more them 1 word at a time. That improved, but when I went home, I had slurred speech, it has gotten worse, due to my G.E.RD., I have always had a little trouble swallowing, but now it is much worse. Due to my 2 hospital stays, I was on Prednisone 24 days. Now they say I may have ALS, that is almost a death sentence. I had a MRI, no major strokes just tiny TIA,s Brenda warner ******