Hi ferensway
I can't tell you what you 'should' do because people have to make up their mind about what they wish to disclose.
The question asks people to indicate if they are having any treatment. It's not helpful to just put the word treatment. If someone is having physiotherapy, just put physiotherapy. If they're having counselling - put counselling. Personally, I think the UC staff are busy trying to manage the migration process, and I've yet to hear of anyone being asked about their medical conditions.
However, you have to do what feels right for you.
BIS
Nothing on this board constitutes legal advice - always consult a professional about specific problems