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Tracking Blood Sugar

eric.jain.name

21–30 of 81 posts

Re: Tracking Blood Sugar

#21

I wear a FreeStyle Libre every day, AMA. It's very good for T1s, of course. It's reliable enough - the biggest downfall is that it's around 15 minutes behind real-time, ie, what you can measure with blood. Sometimes it can feel 'stuck' too, and change rapidly between a short amount of time. The second model, which I am waiting to try, includes Bluetooth alerts if a trend high or low is detected. This may make it even…

Drink water if it feels to be stuck. Usually a symptom of dehydration.

Re: Tracking Blood Sugar

#22
post #15

Earlier quoted context omitted.

It seems to still be invasive: https://www.freestylelibre.us/support/faq.html#faqTabstab-3 > The sensor is applied to the back of the upper arm with a simple, disposable device called an applicator. When the sensor is applied, a small (5mm) filament is inserted just under the skin, and held in place with a small adhesive pad. 'Inserted just under the skin' means it's still invasive, but that sounds nicer than regular…

Per the people I know who have tried it, including the author of this post, it's totally painless. One can debate whether or not a filament you can't feel is invasive, but for all practical purposes it's the same as no filament. For clarity: the measurement you pasted is the length of the filament. The width/thickness is ridiculously tiny. Basically, this product has the same UX as a nicotine patch.

From a design perspective definitely invasive. Design strategies and regulations change greatly for products which penetrate the skin. But you are correct in that it is a patient friendly device without the associated burden of lost invasive devices.

Re: Tracking Blood Sugar

#23
post #15

Here's a second non-diabetic who tracks their glucose with the same non-invasive device and started analyzing it. Blog post: https://richardsprague.com/notes/cgm/cgm_analysis/ Slides from presentation last week: https://www.slideshare.net/richardsprague/quantified-self-se... He also tweets about it: https://twitter.com/sprague

It seems to still be invasive: https://www.freestylelibre.us/support/faq.html#faqTabstab-3 > The sensor is applied to the back of the upper arm with a simple, disposable device called an applicator. When the sensor is applied, a small (5mm) filament is inserted just under the skin, and held in place with a small adhesive pad. 'Inserted just under the skin' means it's still invasive, but that sounds nicer than regular…

If you travel a lot it’s invasive in that you can’t really wear it through full body scanners.

Re: Tracking Blood Sugar

#25
I've been using one of these for about 6 weeks, and I find it is not very accurate, but the convenience that allows checking the readings very often nearly makes up for the huge error bars. The libre freestyle 14-day is usually within 15 mg/dl when the reading is between 80 and 100, but above that range, it is usually off by 20 to 30 percent of the correct value (not 20-30 mg/dl) and mine has never read much higher than the finger-stick test, only lower. The lower numbers make me inclined to believe it, but they are simply not true, the meter gives only about one significant digit of accuracy throughout its range, and it is pretty far off or refuses to produce a reading when my blood sugar goes below 60 mg/dl. Still, being able to see at a glance whether one is 100 or 200 is quite useful. Medicare pays about $500/month for the attachable sensors, which are extremely convenient and non-problematic so far.

There is a far better wearable system ready to go but not in production, a combined sensor and automated insulin dispenser, that has passed human trials, but no one wants to go into production with it because of liability issues. Given that people are riding in self-driving cars and landing in aircraft on autopilot, each of which are also potentially fatal and involve a larger set of variables, I wonder if and how long it will take to progress in this regard.

Re: Tracking Blood Sugar

#26
post #19
post #12

Earlier quoted context omitted.

Dexcom has a similar sensor on the market that’s approved for insulin dosing decisions. I don’t know if any of the other continuous monitors have that particular feature which might be important to those who take fast insulins.

Dexcom G5 and G6 are the best available CGM systems for type 1 diabetics. What they add over the libre is a Bluetooth transmitter over the sensor, giving values to your phone every five minutes. Used together with xDrip and AndroidAPS it can easily safe the life of a person using insulin and not waking up to a hypoglycemia, me included. Or work as a part of a closed loop system. The problem with Dexcom is the price.…

My kids transmitters get flaky after about 3 weeks, and I didn’t think you could reset an expired sensor on the G6 the way you could with the G5?

Re: Tracking Blood Sugar

#27

I've been using one of these for about 6 weeks, and I find it is not very accurate, but the convenience that allows checking the readings very often nearly makes up for the huge error bars. The libre freestyle 14-day is usually within 15 mg/dl when the reading is between 80 and 100, but above that range, it is usually off by 20 to 30 percent of the correct value (not 20-30 mg/dl) and mine has never read much higher t…

The libre is meant for monitoring the trend of the glucose, used together with a fingerstick reader. You can calibrate the values if you use xDrip to get better accuracy.

If you're interested in using a closed loop, take a look into AndroidAPS or Loop, how to build one by yourself. It's all open source and works really well. Been a user for some years now. You just need to compile it by yourself and own the right hardware.

Re: Tracking Blood Sugar

#28
post #26
post #19

Earlier quoted context omitted.

Dexcom G5 and G6 are the best available CGM systems for type 1 diabetics. What they add over the libre is a Bluetooth transmitter over the sensor, giving values to your phone every five minutes. Used together with xDrip and AndroidAPS it can easily safe the life of a person using insulin and not waking up to a hypoglycemia, me included. Or work as a part of a closed loop system. The problem with Dexcom is the price.…

My kids transmitters get flaky after about 3 weeks, and I didn’t think you could reset an expired sensor on the G6 the way you could with the G5?

Should be possible with xDrip. Using the G5 still, so no real life experience.

Some sensors get noisy sooner than the others. I noticed they work longer during the winter when its cooler. Last one worked for 4 weeks quite good, but in the summer they stopped working in less than two weeks.

Re: Tracking Blood Sugar

#29

I've been using one of these for about 6 weeks, and I find it is not very accurate, but the convenience that allows checking the readings very often nearly makes up for the huge error bars. The libre freestyle 14-day is usually within 15 mg/dl when the reading is between 80 and 100, but above that range, it is usually off by 20 to 30 percent of the correct value (not 20-30 mg/dl) and mine has never read much higher t…

Are you sure that the reading were 20-30 percent off and not just delayed? Libre and other sensors measure sugar level in the extracellular fluid and it takes some time before glucose gets there from blood.

The delays make the comparison difficult. Also if it gets too high or low then people react and quickly change the slope of the graph, then the sugar level in the extracellular fluid would not reach the same extremum as the sugar in the blood.

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