The medical history questions should be answered based on the date you get the quote. When you then lead on to declare your conditions, we may ask you some follow-up questions to get a better idea of how you are/were affected.
If for example, you have visited a doctor within the past 2 years, you should select 'Yes' to the medical history question asking this, even if this would be outside the 2 years when you go on your trip.