In the UK, we wouldn't generally class depression as bi-polar.
Indeed most cases seen are "mild to moderate depression." Sometimes over-medicalised, and some would say, over treated.
However we want to play around with the labels though, an admission for a psychiatric illness should not be covered up.
Telling porkies to your AME is a little like sleeping with your sister in law....it seems a good idea at the time, but inevitably it will come back to bite you in the bum.
So I'm told.