Insulin deficit at breakfast

Not certain that I am framing this question correctly but here goes…I think this question might also make sense to the Loopers? Not sure.

The Omnipod 5 when running on Auto mode does a good job (for me) of limiting high and low BG during sleep. It has kept me right in my preferred range through the wee hours and at wake up time. But I have noticed that my breakfast bolus has been completely ineffective at preventing a high (250+) BG that can last for hours. Lunch and dinner do not have this problem, only breakfast since starting the Omnipod 5 about 10 days ago (I just started my 4th pod).

I have noticed that the Auto mode shuts basal delivery all the way down to zero for 1 to 2 hours before I wake on most nights. With Dash and pre-Dash I used a basal of 1.25U/hr starting at 4 AM until 10AM to combat dawn phenom and it must have been also covering part of my breakfast. Could the Omnipod 5 Auto shutdown of basal for 1-2 hours at dawn be causing an insulin deficit that hits me after eating breakfast? Should my breakfast bolus be arbitrarily increased to account for the “missing” basal? Or using a different I:C ratio at breakfast?

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It shuts it down at dawn, and then how long is it before you eat?

Sounds like it could definitely cause a problem!

There is nothing you can do as far as basal settings on the Omni5, right? Like it makes up its own?

You could probably adjust your IC. Or add fake carbs (like if you are eating 50g, tell it you are eating 80g or something along those lines).

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On the other hand, it is supposedly designed to “learn” and make changes over time. You could ride it out for a while and see if it actually changes anything?

:man_shrugging:

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May be experiencing dawn effect? Liver dumps glucose upon waking. You could try a small bolus when you get up.

I have similar, and Tandem IQ reduces my programmed wake up basal most days. So I just bolus knowing BG will soon rise when i get up.

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It has certainly been given a chance to learn a lot in a short period of time, my daily routine has been like the 3 Stooges during this break in period. But the algorithm seems to be limited to adjusting basal up and down with a one hour predictive look ahead. I haven’t seen any auto mode adjustments to suggest it learns a daily pattern such as FOTF rise, breakfast is always large and always at a certain time, etc.

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Dana Lewis of Open APS calls what you describe Negative Insulin On Board

https://openaps.readthedocs.io/en/latest/docs/Customize-Iterate/optimize-your-settings.html

Don’t know there’s much you can change with O5 algorithm :man_shrugging:

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With auto bolus DIY Loop, I will give myself fake carbs to prevent suspension of basal by the algorithm. This is only when I know I still need the basal though! Loop doesn’t have any ai to learn from past experience though so adding fake carbs doesn’t effect future use of the algorithm. It sounds like OmniPod 5 DOES implement some ai to learn. Sounds almost more difficult to manage than Loop since the user has less control. Can you enter an insulin sensitivity factor by period? Maybe you can adjust that for dawn periods?

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It has the “built-in” carb delivery times of 1, 2, and 3 hours.

But I didn’t realize until I started clicking around on it that you can also create a carb with any delivery time you want, from 30 minutes up to 8 hours.

So for example, if you need to do a higher basal for a while, you can make them “8 hour carbs”.

I am thinking that I might want to modify the code to make it up to 24 hours. For things like taking steroids or whatever, it would be helpful to have that option.

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The defaults in LOOP-master are 2, 3, and 4 hours (lolly pop, taco, and pizza are the default icons.) After selecting one, it’s easy to scroll to another duration (up to 8 hours as you said). When taking glucose, I scroll the hours to 0, which automatically changes the minutes value to 30.

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Yes, if I eat something with bread in it, I usually scroll absorption time to 6 hours. In general, Add Carb Entry feature allows Absorption Time up to 23 hours in the LOOP-master branch, so you could use this feature @Eric .

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With Omnipod 5, this is feasible by (1) switching out of Auto and into Manual mode. This activates the normal Dash menu which allows extending a bolus up to 8 hours. And temp basal etc. are available. Only downside is switching back to auto mode is not allowed while a temp basal is running or an extended bolus.

I am seriously trying out the Auto mode so will probably not do the extended bolus/temp basal unless all other attempts to cure the breakfast spike are failures. Today I tried increasing my bolus by about 20% and splitting the bolus into 5 units via PDM and 4 units via syringe. Seemed to help, the spike was short lived anyway.

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Using Dash I often use a high basal overnight to cover carbs; it’s really just a temp bolus. I also see a morning spike from tea - I bolus for 10g but that’s only a couple of oz of milk, nothing else. Since you can do a bolus in “auto” mode why not just whack in something to match the high. For me at 250 that would be around 4IU; very big for me, but if you are sticking at 250 and your /hour bolus is 1.25 for dawn phenomenon (so that’s 7.5IU less whatever your basal is) that may not be large.

Another approach is to delay breakfast; I don’t do my breakfast until many hours after I get up, the tea is just a necessary british thing.

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@jbowler Would you need to bolus for the tea without milk? (Not that you would ever drink tea black…:teapot:)

No; I don’t need to bolus for iced tea (unsweetened of course) and, in general, unsweetened tea drinks are fine. I don’t always bolus for coffee either; I can just about notice it, 1g a shot.

I do need to bolus, either a temp bolus or something explicit, in the morning and this makes it difficult to judge the milk requirements. I think I need one or two units extra in addition to the tea. Generally I take tea (1U), correction (as required) and a 2 hour temp basal (+0.5IU/hr).

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That did not work well. The algorithm immediately reduces my basal after a bolus, reduction apparently because IOB is increased. Watch for the full description on a new thread, coming soon.

It can’t really do anything else apart from switch out of “auto” mode; the background delivery rate (“basal”) is based on IOB, that’s the algorithm! It does, however, do what I would want - instead of doing a slow correction over time it does an immediate correction. This allows the algo to be kicked in the ■■■■ and seems to address the question raised by @eric elsewhere about making the algo more aggressive.

It allows you to preemptively bolus for an event that you know will happen, you might have to include some of the background dose too if you know that the even won’t happen for 30 minutes or more.

That is what I ended up doing (it worked). I switched to manual mode before eating and stayed manual for the meals and afterward. I stayed in manual mode until the CGM trend told me whether a correction would be needed or not, and until the correction bent the curve back downward towards in range. Then switch back to Auto mode. I dont like the way the algorithm handles correction bolus so this is my workaround which is not too difficult.

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I was thinking about my experience with the 670 and this similar situation. Overnight on the 670 I’d often get low basal delivery that didn’t compensate for waking rises. My solution was to overbolus ahead of time, ie normally 4 units 15 minutes in advance of breakfast turned into 6 or 7 units 30 minutes ahead. Auto mode had settings for ISF and Active Insulin Time, so even though it would shut down for most of the active time the over bolus corrected for that time it wasn’t delivering basal.

Is it my understanding that O5 doesn’t respond well to an overbolus (or its contraindicated) because of the AI learning ISF and Active Insulin Time?

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That has been my experience so far…O5 Automode responds poorly to over bolus. I solved this issue by switching to manual mode about 1/2 to 2 hour before meal. Manual mode reverted back to my programmed basal, seemed to be necessary to have that basal on board in order to stay with my usual ISF ratio. Manual mode is also needed to allow extended bolus.

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I use Dexcom and Omnipod Dash - only take 0.1units from midnight to 3am and then 0.35 units from 3-6 am. Rest of the time it’s 0.4 units and then bolus depending on what I’ve decided to eat.

My basal is programmed but I lower and raise it as need be. The Omnipod 5 is likely different but you’d think the the basal would be programmed as we’re all so different. Sure hope you get the results you want! :slightly_smiling_face:

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