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Eye damage from reducing Blood Glucose too quickly ?

I

ianf0ster

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Discussion from the 'blue' diabetes forum
A user replied to me about me not seeing warnings about permanent eye damage from reducing BGs too fast in Type 2's by cutting carbs too quickly:
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You haven't read much then, Type 1's are also told to bring levels down slowly

My story, eye test at the opticians a few months into 2016, nothing wrong and not even a change in lenses required, November 2016 diagnosed with Type 1, brought hba1c down too quickly due to hypo's through the night and not waking, lowered carbs too quickly etc, December 2016 at the opticians because I knew something wasn't right despite a lot of members on here telling me it was "normal" and would settle down, they picked something up and I was referred to ophthalmology, I was diagnosed with Diabetic Macular Oedema (fluid behind the eyes) and started on eyelea injections a week or so later (yes eye injections) and required numerous of these, the only thing they and my diabetic consultant can put it down to is lowering things too fast, then 2018 diagnosed with proliferative retinopathy in both eyes despite in my consultants words too tight control, again they put it down to the earlier quick reduction
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My response:

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Thanks for that.

I understand the need for Type 1's to avoid hypos, but had not before seen anybody specifically mention permanent eye damage in the context of a Type 1 (or a Type 2 except in here) moving from high BG to normal ranges too quickly. Let's exclude hypos from this since that is danger of death rather than the comparatively less severe one of eye damage, though some - possibly even me might prefer to be dead than completely blind.

I wonder how common this eye damage is because I know 2 people who dropped their BGs very fast from pretty high (HbA1C over 100) to normal range BG inside of 2 weeks and they were saying vision distortion was only temporary until body had adjusted to normal range BGs, Sorry but don't know their actual post-prandial BGs when they were diagnosed, but they immediately bought BG meters and went Keto (not just Low carb), so BGs would have dropped like a stone, except not down into the hypo range.


Not sure if you and these two were lucky, or if you and @L######### were unlucky. However I will mention this potential problem in the 'red' forum.
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Well, it's well documented on here. I was diagnosed with Macula oedema a few years back in one eye then a year later the other.
Treated with Lucentis on the one eye then Eylia on both. Got the all clear now.
But, the only correlation I can think of was pulling my socks up with the A1c? Bit of a kick in the teeth to be honest getting diagnosed with something I never even heard of before. & getting away with any retinopathy..

So yep, I'm in the camp of a steady "decompression" when working on the BGs.
 
I think anyone concerned by this should investigate the differences in a type 1suddenly reducing their levels using insulin and a type 2 doing so with diet. And also the likelihood of this happening alongside the likelihood of full recovery.
I am not trying to diminish this issue, just to highlight I’ve read less worrisome things relating to the outcome for type 2 doing this quickly.
 

It could possibly depend on where the BGs were for a T2 in the first place?
It's possible an A1c of 50 (off the top of my head.) got down to remission under the pre-D . Could be more favourable than a rocketeer of any type attempting to "click & collect" on a serous mission to put things good. That includes a T2 on insulin.

We need some statistics relating to this don't we...
 
I’m certain I’ve read of this situation in these forums and more detail about the who and why it happens to. I’m fairly sure it is linked to insulin alongside the dropping of levels, not the change alone, hence the issue more likely applying to type 1. It’s late now but some searching tomorrow might find the references …….
 

I have to agree with you regarding this subject matter chat with mainly T1s. & it looks like @ianf0ster was "cross posted."

& yes, personally I'm pretty responsive to exogenous insulin regarding my levels when I go from "wreckless" to model T.
Even on a low carb diet, it can take some "doing." But that's a basal issue my endo will not see eye to eye on.
The bolus issue is a working profile problem with some of the "usual suspects."
Even fasting it can go top heavy.. Basal checks & I don't eat for a good number of hours prior to a certain activity.

Having said all this.. I do empathise with the cross poster on the "blue forum."
 
This site, written by an ophthalmologist, discusses sudden improvement in control:-
"If you suddenly improve control and your HbA1C drops the retinopathy may need laser treatment. The benefits of an HbA1C drop, say from 75 (9%) to 53mmol/l ( 7%), are long term. The retinopathy may actually deteriorate in the short term, and so require laser. If this is difficult to understand, ask your ophthalmologist to explain.
After two-three years however, assuming you have any laser that may be necessary, you will be better off and the retinopathy will be less active than it would otherwise have been." (Bolding is mine.) http://www.diabeticretinopathy.org.uk/prevention/hba1c_and_retinopathy.htm#sudden
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This is most likley to occur when someone has had a period of poor control (this can be before diagnosis for people with type 2) then improves control rapidly.

There is information about preventing rapid progression here:- http://www.diabeticretinopathy.org.uk/retinopathyprogression.htm
 
This may all be a coincidence but I did low carb immediately after diagnosis and I had a blurry/cloudy right eye for one week if not more. I went to see an ophthalmologist, and by that point a lot of the eye issues had cleared up. He couldn’t find anything wrong. I was worried it was diabetic retinopathy, but he simply laughed and said “at age 35 with less than 3 years with diabetes you’re not going to have retinopathy- I can tell you that for certain without looking at your eyes”

Any way everything was checked and thankfully nothing wrong with my eyes phew
 
Very short term blurriness can simply be the eye adjusting to being bathed in a lot less glucose, which is a temporary th8ng last just a few weeks. Quite different to the potential damage (retinopathy/macular) instant drop seen in insulin users. The trick is in differentiating the two. So it’s always worth getting checked over (without panicking) but just be cautious about buying new specs for a few weeks if nothing worrying is found
 


Oh that’s interesting ! Thanks
 
My own experience was that my retinopathy accelerated from background to full blown blindness (rectified by a double vitrectomy) during pregnancy and beyond i.e. a time of high insulin needs due to insulin resistance but tight control of glucose levels followed by post birth rebound to lower insulin but looser control of blood glucose.
If the body likes stasis in both glucose and insulin levels then having too much of one, the other or both tends to lead to disease. IF you are type 1 then 20 years of going over 7% is said to be the high risk point but we know that type 2s get complications sooner into their diagnosis possibly because their insulin levels have been high for years before their blood glucose levels crept up so maybe these problems are latent and easily triggered by a sudden change in glucose/insulin?
 

I have a feeling (but only a feeling) that you are right about it being related to insulin rather than Low Carb as such.
Both the two people in the 'blue forum' who responded with personal experiences were insulin users and had driven down into hypos before the said 'permanent eye damage'. Though one of them was a T2 on insulin.

However it would be good to resolve the marked difference in advice between the 2 forums. If the problem exists to unmedicated T2's then I don't wish to be complacent about it. Neither (if it doesn't exist in non-medicated T2's) do I want to ignore potential scar-mongering.
 
How strange that the first thing I see is this post on my return from the eye centre today.
I had told my consultant that there may be a possible change to my eyes since I had recently stopped eating most carbs.
He told me that the pressure in my right eye is 16 (good) but then he was surprised to find the pressure to be 28 in my left eye!
He didn't seem to understand why, and has prescribed medication for two months, and then a return visit. If not improved he thinks I will need an operation. Surely this cannot be linked to my suddenly stopping carbs?
 

This is precisely what we are trying to find an answer to.
- Is it coincidental?
- Is it due to a long period of uncontrolled (high) BG
- Or is it due to a sudden drop in BG.

Though A). You don't yet know if your high pressure problem is temporary or not.
B). Up until now people have been talking about Retinal and Macular problems - not Glaucoma - which appears to be your situation.

Note a quick google revealed that " Another cause is the side effect of certain medications such as steroids."
 
HurricaneHippo said:
This may all be a coincidence but I did low carb immediately after diagnosis and I had a blurry/cloudy right eye for one week if not more
Click to expand...
Yes, it is not unusual to get a temporary blurring when good control is instigated due to the time it takes for the lens to equilibrate to the new glucose levels.
 
ianf0ster said:
I have a feeling (but only a feeling) that you are right about it being related to insulin rather than Low Carb as such.
Click to expand...
The problem is linked to a sustained period of poor control followed by a rapid, large improvement in control. Theoretically, this would be regardless of the method of improvement but historically, the people most likely to be affected would be people who are type 2 when starting insulin or people who are type 1 'turning over a new leaf'. However, with the increased popularity of low carbing nowadays, it could be a risk to low carbers with type 2.

From the site I referenced earlier:-
If someone is diagnosed with type 2 with an HbA1c of 55 mmol/mol and had a normal HbA1c last year then they are unlikely to have problems in bringing their HbA1c down to normal levels quite rapidly as a) they haven't been diabetic for long and b) a normal HbA1c is less than 33 mmol/mol lower. If someone is diagnosed with type 2 with an HbA1c of 85 mmol/mol and has not had their HbAic measured in the last 10 years then it 's possible that they have had poor control for a few years of undiagnosed diabetes so it might be wise to take their improvement in control gently until at least they've had their first retinopathy screening - if there is no retinopathy detected at first screening, there is little risk of problems from further improvement in control. Someone who is type 2 who starts on insulin will have had diabetes for some years with increasingly poor control (insulin is not generally offered unless control is poor). This is long enough to cause some retinal damage so the person may be at risk of getting an initial worsening of retinopathy when they start on insulin.
 
I have tweeted about the differing views on this in the 'red' and 'blue' forums. Sent question to several doctors who advocate non medicated methods of dramatically lowering BG - not just low carb.

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