Prednisone and Antidepressants

I’m 63 and was diagnosed with PMR 4 months ago. My life is upside down. I have tapered down to 20mg Prednisone, not without a lot ongoing pain and other symptoms. I have taken Zoloft for 20 yrs, but noticed from the start of Prednisone that my mood has definitely become much more “positive” in spite of the the sudden life changing impact of PMR. I read that Prednisone can impact the same brain areas as Zoloft. As I have tapered Predisone from 50mg, my mood remains “positive”, in spite of the pain. As a result, I have slowly tapered my Zoloft (my hope is to slowly eliminate it). There are lots of other things I could mention that may also contribute to this, but am focusing on the chemicals.
Has anyone else experienced anything similar related to mood and Prednisone?
As you taper to “zero” Prednisone have people noticed a drop in mood due to no Prednisone?
Thanks