Consistent low glucose during sleep

[danielmg]

Hi All,

I am due to be referred for further testing as per consultant, as it was brought up in my annual review that I'm suffering from consistently low glucose readings (measured mainly via Libre) throughout duration of sleeping. I just wondered if anybody else has had further testing or diagnosis from something similar to this. It was mentioned that I would have a cortisol function test to check for Addison's Disease.

It is very strange that my glucose will read at 4 or below, with very minimal symptoms, consistently whilst sleeping. I have been asked to check BG as well as sensor to compare results, however the other issue i've noticed is that glucose will elevate slightly whilst awake, and then drop again to same levels when I go back to sleep.

I recently started taking SSRI medication, and unsure if this may be contributing to these results, however consultant never mentioned this during review.

Thank you for any help or advice in the meantime.

 

[Inka]

Did your finger prick tests confirm the lows? Could you have been lying on the Libre? What basal are you on and when do you take it?

Lots of questions there!

 

[rebrascora]

Hi Daniel. I am currently having problems dropping low during the nigh, particularly when I do a lot of exercise during the day. I have cut my evening Levemir down to nothing and I make sure my levels are up to 9 or 10 at bedtime and they gradually drop whilst I sleep with no real active insulin on board. I don't think it is unusual not to feel hypo symptoms whilst you are asleep around the 4mmol mark but if you drop to low 3s, it should wake you.
Many people, myself included find that Libre reads a bit lower at low levels and a bit higher at high levels, so when my Libre reads 3.5 a finger prick might show 4.3. I know what you mean about it rising when you finger prick through the night. As soon as I put the light on and sit up and get sorted with a test strip in the machine my levels will rise and then drop as soon as I go back to sleep so difficult to accurately check those low readings.
I am starting to think that this is just where my fitter healthier body wants to be. I have tried setting an alarm and checking and taking jelly babies if I am below 5 but it drops again despite no active insulin when I go back to sleep. Last night I woke at 4am on 4.2 having gone to bed on 10.5 with no active insulin other than the tail end of the morning Levemir. I toyed with eating 2 jelly babies but decided to wait and see what happened and it wobbled up and down between 3.8 and 4.3 for the remainder of the night.
I think it is highly possible/likely that this also happens with non diabetic people but we don't know as the majority don't have Libre and that the Libre is possibly reading slightly lower than the actual BG level.

I am experimenting more with mine but exercise/strenuous activity the day before is definitely a factor for me. Going to bed on a higher BG level and having a snack like a chunk of cheese or some nuts is helping.

 

[pm133]

@rebrascora, presumably if your glucose is dropping in the night and you have no basal, your pancreas must be producing some insulin itself? I can't see how else your glucose levels could be dropping.

 

[rebrascora]

@rebrascora, presumably if your glucose is dropping in the night and you have no basal, your pancreas must be producing some insulin itself? I can't see how else your glucose levels could be dropping.

My theory is that my muscles are sucking the glucose out of my blood to replenish their stores whilst I am sleeping and perhaps my liver is also clawing some back. It is definitely connected to the muscle burn exercise during the previous day(s) for me. If I don't exercise I need evening basal insulin. If I do light exercise like a brisk walk, it doesn't have such a dramatic effect.

 

[danielmg]

Did your finger prick tests confirm the lows? Could you have been lying on the Libre? What basal are you on and when do you take it?

Lots of questions there!

I've tested both BG and sensor just 3 times thus far after waking up during the night. My BG has been lower twice and higher once, but I wouldn't say a very significant difference between them. The other strange thing (that I forgot to mention first time) was that I haven't been taken any basal insulin for ~6wks, and the consultant has recommended I continue with this until my next appointment. I don't even taken alot of bolus insulin throughout day, so it's unlikely that there is any extra insulin on board from what my pancreas must still be producing (or other immune deficiencies causing). I think I may still be within the honeymoon phase to some extent, but honestly a little baffled by some of the results.

 

[danielmg]

Hi Daniel. I am currently having problems dropping low during the nigh, particularly when I do a lot of exercise during the day. I have cut my evening Levemir down to nothing and I make sure my levels are up to 9 or 10 at bedtime and they gradually drop whilst I sleep with no real active insulin on board. I don't think it is unusual not to feel hypo symptoms whilst you are asleep around the 4mmol mark but if you drop to low 3s, it should wake you.
Many people, myself included find that Libre reads a bit lower at low levels and a bit higher at high levels, so when my Libre reads 3.5 a finger prick might show 4.3. I know what you mean about it rising when you finger prick through the night. As soon as I put the light on and sit up and get sorted with a test strip in the machine my levels will rise and then drop as soon as I go back to sleep so difficult to accurately check those low readings.
I am starting to think that this is just where my fitter healthier body wants to be. I have tried setting an alarm and checking and taking jelly babies if I am below 5 but it drops again despite no active insulin when I go back to sleep. Last night I woke at 4am on 4.2 having gone to bed on 10.5 with no active insulin other than the tail end of the morning Levemir. I toyed with eating 2 jelly babies but decided to wait and see what happened and it wobbled up and down between 3.8 and 4.3 for the remainder of the night.
I think it is highly possible/likely that this also happens with non diabetic people but we don't know as the majority don't have Libre and that the Libre is possibly reading slightly lower than the actual BG level.

I am experimenting more with mine but exercise/strenuous activity the day before is definitely a factor for me. Going to bed on a higher BG level and having a snack like a chunk of cheese or some nuts is helping.

Thank you for the detailed reply @rebrascora. Next time it happens I may have a small amount of carbohydrates to see if it drops again, and by how much. The vast majority of nights i'll have a small snack before going to bed as well, but the libre shows the effect of this is short-lived.

 

[rebrascora]

Do you take your Lantus on a night or in the morning? Just wondering if it is your Lantus taking you down? It tends to have a peak of activity about 5 hours after injecting I believe, so if you inject it on an evening that might be the problem in your case.

 

[Ljc]

Hi @danielmg . I am going to tag @Northerner as he does not need any Basal

 

[rebrascora]

Apologies, I missed your other post where it said you no longer take basal insulin.

 

[rebrascora]

Do you have an exertive job or are you doing more exercise like me?

 

[Inka]

It sounds like you’re definitely dropping then. I’d up the carbs in my bedtime snack (what kind of thing are you eating?) and if you’re dropping worryingly low, I’d also set an alarm for 1/2am and test by finger prick and eat a few carbs then too if needed.

So what time do you eat your evening meal and how much do you bolus?

 

[rebrascora]

What sort of readings do you go to bed on?

 

[danielmg]

Do you have an exertive job or are you doing more exercise like me?

I'm currently not at work (and haven't been for about 5 months) due to ongoing issues with mental health. I'm also rather embarrassed to say I haven't exercised at all in this time (and far beyond this as well). My job can sometimes involve alot of walking and moving around (within a laboratory) as well as high pressure situations, however as I haven't used the Libre whilst at work, i'd never detected the low glucose readings over night.

I also normally go to sleep reading at approx. 6-7 on average, but I'm worried about going overkill with the carb intake and sending readings too high (higher sensitivity to CHO during evening, especially with no basal insulin).

 

[Pumper_Sue]

If you have Addison's then you would have low BP and it would drop like a stone on standing up.

 

[danielmg]

It sounds like you’re definitely dropping then. I’d up the carbs in my bedtime snack (what kind of thing are you eating?) and if you’re dropping worryingly low, I’d also set an alarm for 1/2am and test by finger prick and eat a few carbs then too if needed.

So what time do you eat your evening meal and how much do you bolus?

I'll normally have either a wholefood bar (made of dates, nuts) or a piece of fruit (apple, pear, banana). The other minor annoyance I have is that most nights I wear a retainer after brushing my teeth. Therefore I've just bought some small apple juice cartons I could alternatively drink instead of the aforementioned foods.

Most evenings I'll eat my evening meal at approx. 6-7, and likely have another snack at about 10 before bed. My average bolus range is between 2-4u per meal at the moment, so not a lot (even though my carbohydrate intake for this meal would normally be between 60-80g).

 

[danielmg]

If you have Addison's then you would have low BP and it would drop like a stone on standing up.

At my last annual review my BP was a little lower than 120/80, and i've lost a fair bit of weight in the last 6 months without trying (although my appetite isn't the same whilst I've been off work).

 

[Pumper_Sue]

At my last annual review my BP was a little lower than 120/80, and i've lost a fair bit of weight in the last 6 months without trying (although my appetite isn't the same whilst I've been off work).

Your BP is normal 🙂 Lowest I ever managed was 60/40. The ambulance crew and doctors called me the walking dead as they had never seen anyone conscious let alone walking with a bp that low.
You would also have great difficulty in treating low blood sugars because it is a lack of cortisol that would cause the hypos.

 

[danielmg]

Your BP is normal 🙂 Lowest I ever managed was 60/40. The ambulance crew and doctors called me the walking dead as they had never seen anyone conscious let alone walking with a bp that low.
You would also have great difficulty in treating low blood sugars because it is a lack of cortisol that would cause the hypos.

Since i've been off work it hasn't been too difficult to treat daytime low readings, however it has been very difficult whilst at work, despite my best efforts. I realise there could be many reasons affecting what is happening at the moment, so I'm interested to see what comes of the next appointment.

 

[Northerner]

I've tested both BG and sensor just 3 times thus far after waking up during the night. My BG has been lower twice and higher once, but I wouldn't say a very significant difference between them. The other strange thing (that I forgot to mention first time) was that I haven't been taken any basal insulin for ~6wks, and the consultant has recommended I continue with this until my next appointment. I don't even taken alot of bolus insulin throughout day, so it's unlikely that there is any extra insulin on board from what my pancreas must still be producing (or other immune deficiencies causing). I think I may still be within the honeymoon phase to some extent, but honestly a little baffled by some of the results.

Hi @danielmg, as @Ljc says, I haven't used basal insulin for 8 years now - I stopped needing it 4 years after diagnosis. What levels are you dropping to overnight? The non-diabetic level is actually lower than the one we are told to regard as 'hypo' when we are using insulin - it can drop as low as 3.3 and not be considered hypo in a non-diabetic person. So, if you do not have any active insulin (apart from that being naturally produced by your body) then anything above 3.3 is normal. Unfortunately, the Libre won't let you set your range below 3.9, so that can lead to a lot of phantom overnight 'hypos' being registered. They are not dangerous, as they would be if you still had basal insulin onboard, but it does mess up your Libre stats! 😱 There's no harm in having a jelly baby to raise levels a little if it makes you feel more comfortable, that's generally what I do if I wake in the night a bit low 🙂 Note also that your levels naturally drop to their lowest levels in the middle of the night, when your liver is least active.

I had a C-peptide test a couple of years ago which showed that my pancreas is producing a 'reasonable' amount of its own insulin, which is why I don't need the basal. The consultant couldn't provide an explanation other than the fact that diabetes is a very wide spectrum and can vary considerably in individuals. I still need bolus insulin with my meals, about 20 units a day currently. Of course, the other investigations that are taking place for you may reveal a different cause, so hopefully they can pinpoint things for you 🙂

Let me know if you have any questions! 🙂