I'm disabled following an accident.
If your partner has been working and making NI contributions up until recently then he may well be able to claim additional financial support.
As others have said, generally fit and well and getting medical retirement don't match.
I'm assuming he is not fit and well.
He can claim ESA - contributions based employment and support allowance. PIP is also a possibility. They are apparently prioritising new claims and mine recently went through fairly fast.
That money can be used to get a cleaner and buy in additional help.
I looked into medical retirement. I would have been able to access my pension early, and so would have got a monthly payout, but the amount I got would have been significantly less than if I took it at normal retirement age.
In addition, I would have had to be certified as unable to work in any job at all, not just my current one.
I decided it wasn't worth it and I'd rather access my pension at the normal time.
So if he's actually medically retired (ie been certified not capable of working any job, now or in the future) he should be getting a monthly pension, plus can access esa and pip.