What are the recommendations around insulin adjustments on HD?

Danielle reached out to see if I had any resources for adjusting insulin on HD days. She has a client who reports increased insulin resistance a few hours after HD.

The impact of HD on BGs

Evidence suggests that hemodialysis can actually reduce insulin resistance and can be associated with reductions in blood glucose levels, especially after dialysis. In fact, a 2022 systematic review reported that most guidelines recommend reducing the basal insulin by 25% on dialysis days in anticipation of this drop in blood glucose values.

If BGs are supposed to be going down – then why is this patient going up?

Here’s the caveat to this, in this 2017 paper (for example) examining the impact of HD on blood glucose values – they were using a dialysate solution that didn’t contain glucose. The dialysate solutions that I have worked with in clinical practice have always contained glucose! This is an obvious difference in what this paper is describing than what I have seen in my clinical practice.

Which is a good reminder to take a quick peek at the methods section of the papers, so you know if you are comparing apples (your clinical population) to apples (the studied population).

How much glucose is in the HD solution?

Well that might depends on your unit. In Canada, Health Canada approves dialysate solutions that contain between 0-12.0mmol/L of glucose. Though the HD units I have worked on used a 5.55mmol/L glucose-concentration solution. And unlike things like potassium – where I had access to a say a K1, K2 and K3 bath, the glucose concentration in our solutions was static and so I rarely actually even thought about it.

Is it better to have glucose in HD solutions?

Several studies have compared HD solutions with and without glucose. Most agree that the rates of hypoglycemia during HD are lower when solutions contain glucose. Some report lower blood pressures and serum sodium levels as well – though this isn’t a consistent finding. So, on the balance it appears that HD in glucose solutions is good because it prevents hypoglycemia.

Though I wonder, if this may be contributing to this patient’s hyperglycemia post HD – as they are getting some glucose exposure during their HD run. Albeit, a very small amount.

Is insulin dialyzed out?

The other potential is that the dialysis could be impacting their circulating insulin levels. I don’t know if this patient administers insulin – but I thought it would be an interesting point to consider. However, in general, insulin is not thought to be dialyzed out. This resource reports that the % dialyzed out for insulin determir is negligible.

Ok – higher blood glucose levels POST-dialysis is unlikely to be related to loses of insulin during the HD session. On to the next assessment piece…

What are they eating?

As a dietitian – this is obviously my favourite question! I am starting to wonder how the dialysis session is impacting their diet and if this is contributing to variations in their blood glucose levels. When I work with HD patients I always attempt to ask them about their meal patterns on HD and non-HD days because my experience is that they are vastly different. This is likely in no small part related to the HUGE time commitment of HD, meaning that no matter what run you are on (morning, afternoon, evening or nights) there is likely overlap with at least one meal.

The other interesting thing to consider is whether or not they eat during dialysis. Which is a huge contentious issue, in that many HD units don’t want folks eating during dialysis. Though I am going to save that discussion for another day!

Back to Danielle’s question

Danielle, the easy answer to your question is that the recommendation is to lower basal insulin by 25% on HD days, because the most common concern about blood glucose levels after HD is actually HYPOglycemia vs HYPERglycemia.

So, in the case of your patient, having hyperglycemia, this recommendation appears incorrect (unless the issue is that they are actually going low and then getting into some sort of roller coaster pattern and I suppose could be something to check out, if you haven’t already!).

Otherwise, it looks like the options are to adjust the insulin up, though this could be tricky depending on whether or not this patient has access to short or long acting insulin and the duration of the hyperglycemia. Also I could not find any guidelines for this scenario.

Our other intervention is a review of the diet. Is it possible for this patient to reduce the glycemic load of the meals/snacks they are consuming during this time? Or does the meal and snack timing need to be reviewed? Is this patient feeling super hungry after dialysis and inadvertently consuming a huge carbohydrate load?

Thank you Danielle!

Thanks so much for the question Danielle. If you (dear reader) have a question for me, please don’t hesitate to reach out. Leave me a comment or send me an email at contact@kellypicard.com