alt Hacker NewsI'm a T1 diabetic, have worked on open source diabetes-tech (OpenAPS), and have used a number of different CGMs (though not this one specifically). This story... does not make very much sense.
CGMs (of any brand) are not, and have never been, reliable in the way that this story implies that people want them to be reliable. The physical biology of CGMs makes that sort of reliability infeasible. Where T1s are concerned, patient education has always included the need to check with fingerstick readings sometimes, and to be aware of mismatches between sensor readings and how you're feeling. If a brand of CGMs have an issue that sometimes causes false low readings, then fixing it if it's fixable is great, but that sort of thing was very much expected, and it doesn't seem reasonable to blame it for deaths. Moreover, there are two directions in which readings can be inaccurate (false low, false high) with very asymmetric risk profiles, and the report says that the errors were in the less-dangerous direction.
The FDA announcement doesn't say much about what the actual issue was, but given that it was linked to particular production batches, my bet is that it was a chemistry QC fail in one of the reagents used in the sensor wire. That's not something FOSS would be able to solve because it's not a software thing at all.
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That is odd. A too-low reading would result in less insulin and a high blood glucose, which can be extremely uncomfortable but is not immediately deadly.
If it had read too high, it could result in an insulin overdose, which can indeed bring coma followed by death in fairly short order.
>If a brand of CGMs have an issue that sometimes causes false low readings
Not sometimes. "Over an extended period".
"Abbott Diabetes Care stated that certain FreeStyle Libre 3 and FreeStyle Libre 3 Plus sensors provide incorrect low glucose readings. If undetected, incorrect low glucose readings over an extended period may lead to wrong treatment decisions for people living with diabetes, such as excessive carbohydrate intake or skipping or delaying insulin doses."
Months of high blood glucose level can worsen patient's condition or if high enough even put them into hyperglycemic coma in weeks(?).
[0] https://www.fda.gov/medical-devices/medical-device-recalls-a...
I'm not a diabetic, but even I was skeptical of the title "Seven Diabetes Patients Die Due to Undisclosed Bug"; this draws a very direct 1-to-1 association when in reality, we know that a death would be the result of multiple failures/oversights.
I thought this article would try to sell us on the benefits of formal software verification or something... Though of course, you can't formally verify complex human biology.
as a T1D parent, agreed, this a nonsense article and shows the author has no real experience.
> This story... does not make very much sense
Agreed. This story is clearly pushing an agenda to an extreme degree. They spent a lot of time linking to different things and past stories, but the claim of having killed seven people gets almost no coverage in the story. Can we at least get a source to where they’re getting that information?
> CGMs (of any brand) are not, and have never been, reliable in the way that this story implies that people want them to be reliable
This has been my impression. I briefly used an Abbott Lingo to help me understand some health issues I was experiencing.
It's always been clear to me (including in the app and documentation) that CGMs are an extremely convenient tool as a first line - but struggle in extreme circumstances. And, let's be clear, if you would generally know if your body is in one of these extreme circumstances. You'd probably be feeling like shit.
That's not to mention the device in question, the Freestyle Libre, is (to my understanding) by far the most popular insulin-dependent diabetes CGM available.
This article is equivalent to calling the Boeing 737 unsafe because it's had the most Full Lost Events while completely ignoring it's flown 238.84M flights (which is basically more than the entire rest of the list combined).