I had a stroke in Nov last year and just had to stop driving for the customary 4 weeks and now have the all clear so dont need to tell dvla. I know if you hold hgv licence you have to surrender it for a year having had a stroke but can I still train to obtain one? Also anyone know how long my medical is valid for on a provisional (I did it Jan 2020) .
I hope you are recovering well.
My understanding is that you should tell DVLA about anything that would affect your fitness to drive according to their parameters (you can get your hands on a D4 at some Post Offices for reference). Your doctor also has a responsibility to tell the DVLA, but may not have the information that you hold a provisional lorry licence.
In terms of the medical, it is the same situation as a full licence as far as I am aware. On first renewal after the age of 45, a medical will be due. Before this, you will have to declare that everything is fine medically by declaration on renewal.