One thing to maybe keep an eye on is MyDiabetesMyWay.
We've had it in Scotland for about 10 yrs now, and it seems that there's moves afoot to roll it out to England too. Somerset seems to have already done so. I've no idea whether the proposed roll out is one of these new shiny things which will just grind to a halt or whether it will be a runner.
It's not full med records, just those relating to diabetes.
I can see graphed and listed a1cs back to about 2001, and various other bits and pieces over long time frames like bmi, blood pressure, weight, cholesterol, albumin/creatinine, eye tests.
One of the interesting things was that, you know how we occasionally get those "early signs of diabetes related eye changes but dinnae worry" letters, the MDMW site shows a bit more of the background detail. It gives the results for each eye. Over a few years, I might have the right eye fine, left eye showing signs, then next year, right is showing signs but left is fine! Just goes to show how the testing can be a bit subjective and/or minor damage can repair itself.
Couple of links for anyone interested in it:
Here's how it looks up here in Scotland:
https://www.mydiabetesmyway.scot.nhs.uk
Here's Somerset's take on it:
https://somerset.mydiabetes.com/AboutUs.aspx
Here's the company behind it (note: one of the principals is Dr Deborah Wake - my last 6 month checkup was with her - she's a player when it comes to diabetes tech)
http://www.mywaydigitalhealth.co.uk
And the NHS saying they plan to extend across England:
https://apps.beta.nhs.uk/my-diabetes-my-way/