Risks of rapid change in blood glucose.

You are about to be started on a  GLP-1 analog (tirzepatide/Mounjaro, Ozempic/semaglutide) /insulin /hybrid closed-loop pump

This is important for getting your blood sugars under better control and in the long-term will protect you from worsening eye disease (retinopathy), nerve disease (neuropathy), kidney disease (nephropathy). However when we tighten control, occasionally your eye disease can get worse before it gets better. This is because your blood vessels have been used to high blood sugars for a period of time and it will take some time to adapt to better blood sugar control. Our current understanding is that the risk is small but occasionally can cause bleeding and worsening of your vision.

There is absolutely no doubt that in the long-term better blood sugar control is protective for your eyes, nerves and kidneys.

When you are referred for improvement in diabetes control, I am aware that you would have been waiting a long time to get your pre op appointment. You would like to get your sugars under good control however rapid changes in your blood sugars can result in some unexpected outcomes which you should be aware of.
Creator: Jared Araujo

Risk of progression of  retinopathy

Tiny blood vessels at the back of the eye ( Retina) are very sensitive to blood flow. If these blood vessels are used to high blood sugars over a long period of time, they can adjust to high blood sugars. If we improve control rapidly, this can result in reduced blood circulation and new tiny blood vessels can grow. It can also lead to swelling at the back of the eye ( Maculopathy).

Risk of hypoglycemia

When control is tightened, you can have more pronounced drop in blood sugars. This is a hypoglycemia. ( when your sugars drop below 4.0 mmol/l ). This can occur unexpectedly or after exercise. One should be particularly careful when driving and monitor carefully as advised by DVLA. these rules are your blood sugars should be above 5.0 mmol/l to start driving You should check every 2 hours into a long drive You should carry short acting carbohydrates in the car within easy reach If you do have a hypoglycemic episode, you should stop driving and avoid driving for at least 45 minutes DVLA Rules –

please refer to DVLA website for up-to-date info

Please see DVLA guidance for safe driving 2024

I am confused. so should I not improve my blood sugars?

Not at all.. There is absolutely no doubt that better blood sugars will in the long term help to protect your vision. Poor blood sugars are associated with a 50% increase in risk of losing vision. We should always strive to the best blood sugar control possible. Just do it slowly to minimize the risk

Who is at increased risk?

There is increased risk to anyone who has rapid improvement in control. This may be extreme diets like keto diet. However it is mainly for those who

  • Have had poor control for a long period of time ( >2 years)
  • Start using a pump
  • GLP1 anlaloges (eg Mounjaro, Ozempic etc)
What medications are associated with this risk?

Any rapid improvement can be associated with this. In the past this was with starting insulin. However now it can be with

  1. Starting insulin pump for those with Type 1 diabetes
  2. Changing from open pump to hybrid closed loop pump
  3. GLP 1 analogues.. Semaglutide (Ozempic) Tirzapetide ( Mounjaro) and others.
I am worried about this.. What Can I do?

It is important to discuss this with your Healthcare professional. We do not know the exact risk of worsening retinopathy, but we need to keep a careful  watch

  1. If you are under the eye hospital, please chase up your appointment, particularly if you are overdue an appointment.
  2. If you do have any change in your vision, please go to the emergency department at Eye hospital
  3. make changes slowly.. and if you have retinopathy,
    1. your HCP may slow down increasing your medications  eg your dose escalation may be every 2 months rather than monthly
    2. Your HCL pump setting will start at the most relaxed target and then slowly tighten up.
What about other risks?

This is an important question. Hypos tend to be more frequent, when improving control. This means increased monitoring of blood glucose, particularly

  1. while driving
  2. during and after exercise

What should I do?

  1. Understand that there is increased risk of progression of retinopathy. We can mitigate risks but cannot eliminate this risk completely
  2. Please ensure that your eye screening is uptodate and share your result with your diabetes team
  3. If you are waiting for Eye hospital appointment, please chase this up. This is your responsibility
  4. This risk is maximal in the first few months after commencing treatment. Please be vigilant and notify the team if you are concerned.
  5. If you notice any change in vision, please contact eye hospital

Trials are ongoing to determine this risk and we should have more information by 2027