You're worried that they'll find out you were in hospital for depression? 1. they probably won't be allowed to search for your medic files. 2. The hospital is obliged to give details to some employers but it's not as if you were dangerous to anyone. Having depression in the past is nothing to be ashamed about. I doubt they'll sack you even if they knew this. I haven't heard of a case where someone was sacked because they were in hospital for depression.