Friday, August 17, 2012

Meter, Meter, Pump, and Meter

Meter, meter, pump, and meter,
Too much data would defeat her.
Threw up her hands, said what the hell?
And there she left it very well.

Sometimes you realize why they always say, "Just pick a meter and stick with it."

I have been using Abbott Freestyle products since they were Therasense Freestyle products - 8 years? 9 maybe? They have a tiny blood sampling size, they have a light on the test strip port. They changed their meters to Lite meters - I kept mine. I have 3 or 4 Freestyle Flashes. I championed their continuous glucose monitor; then they bought it back from me. They changed their strips; I stayed loyal. I used the Cozmo Cozmonitor (a Freestyle meter), then the Omnipod PDM (a Freestyle meter).

But I had to go and stir the pot.

I'm planning to switch to the Tandem t:slim this fall and I heard that it will be shipping out with Lifescan's new One Touch Verio IQ meter. I can't stop hearing about this meter. I know the background music for their commercials (it plays during every commercial break for Dora and the Bubble Guppies - because my two year old should be asking "What does your blood sugar meter tell you?"). Several of my bloggy friends are liking it.

Okay, I'll start using the Verio then. Big whoop.

So I checked my blood sugar on it for the first time when I was having hypoglycemic symptoms. The number came back over 30 mg/dL higher than my Freestyle Flash and Omnipod PDM. That's weird, I thought. Tried it again. Same.

Tried it while stable. Same. Tried it while high. Same. Every check was between 30-60 mg/dL higher than the Freestyle readings. I called One Touch. They promptly sent me a new meter. Same.

So what's going on here? Will I go ahead and switch to this meter?

I decided I'd test all the meters I have against the blood draw my endocrinologist would be sending off to the lab at my quarterly checkup...just to satisfy my curiosity.

Now, there's some discrepancy between plasma values and fingerstick values. And the BIG (and I do mean BIG) issue is that FDA allows a meter to be +/- 20% off from the plasma value. You can blame FDA, but FDA says that meter companies are not asking them for tighter. There are groups lobbying for +/- 15%. I'd like to see +/- 10% personally, but anyway...

My point is that I'm no quality control expert and I wasn't conducting an error-free experiment. I just wanted to see.

I loaded up five meters with test strips. I washed my hands. I pricked my finger and got one big drop of blood and began to disperse the blood across all five strips.

I had a lot of blood, so I used that same drop and did it a second time on all five meters.

Just for giggles and because I love to bleed, I pricked a different finger and did the test a third time.

The lowest reading was 78, the highest 128. A range of 50 mg/dL. Surely one of these meters was going to be proven grossly inaccurate.

And yet? My lab draw glucose level was 104. Yeah, like in the meter commercial.

The breakdown of the readings and their accuracy looks like this:

Omnipod PDM -25%  -15% -21%
Verio IQ #1  +6%  +23% +6%
Verio IQ #2  +4%  +22% +19%
Freestyle Lite  -13%  -7% -16%
Freestyle Flash  -22%  -20% -24%

You've got to be joking.

I'm not freaking out about some of the readings being just slightly above the +/- 20%. Again, this was not a controlled experiment, per se. But, if you take the average of these, you get this:

Omnipod PDM -21%
Verio IQ #1  +12%
Verio IQ #2  +15%
Freestyle Lite  -12%
Freestyle Flash  -22%

In a nutshell, my problem is that I feel I can't jump from using meters that are 15-20% below the correct number to 15-20% above the correct number without having some rather serious short-term side effects.

If I'm symptomatic with low blood sugar symptoms at X+20% (meaning that perhaps I'm used to feeling low at lab value 90 and the Flash tells me I'm 60), then what happens when I switch meters and treat a high that's actually X-20% of the number I give insulin for? I will fall to what feels to me like a 30? 40? Because I treated a 180 that was actually a 140?

It's convoluted and it's depressing and it's frustrating.

Hubster tells me to just jump in to using the Verio and give it a few weeks to see if I acclimate to those numbers. I may never look back. My endo says she doesn't care what I use. And, though I could continue to use the Flash, not only is it a meter they don't even make anymore, but it performed pitifully here.

So I'm back where I started. I don't know what I'll do. I'll happily accept advice in your comments (unlike me, I know).

I'm thinking I'll ask my CDE for her opinion in September. Maybe pick up a 90-day script for Verio test strips. Maybe scrap it all and buy an iBGstar (also not known for accuracy). Maybe keep using the Freestyle Lite with the regular Freestyle strips since that seemed to do okay.

13 comments:

  1. I am a One Touch user - I have tried the Freestyle meters (the Pos meter when I did a trial and the Lite), and while I love the small sample size and test strip port light, I have found that they ALWAYS run at least 20-30 points lower for me. We recently were using Freestyle at camp and I opted to continue using my One Touch - I was going to be treating a lot of lows based on the Freestyle numbers if not. My A1C is on par with the One Touch meters.

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  2. Oh how I hate this game... I am a fan of the "finish all of the old strips and switch completely" method.

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  3. I'm with you on the meter inaccuracies. I too have wondered if I need to use the Verio, but I just don't want to take that jump again. After researching both, they're supposed to be highly accurate within 15% (info via their strip package insert), but then posts and pictures like these make me question everything... and want to scream!

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  4. I like the VerioIQ, despite the freaky control-solution-errors I've been experiencing (including with the replacement they sent). But I agree that the values seem higher than I'd been getting with my UltraLink.

    I'm going to stick with it, though - maybe it'll mean a lower A1c without very much effort? Kind of like switching to skim milk. Or at least that's what I keep telling myself.

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  5. Sort of did the same experiment recently! Here's what I found (very inconclusive!): http://delightfullydiabetic.wordpress.com/2012/08/09/my-experiment/

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  6. Blech!!! YUCK YUCK YUCK!!! What's a girl supposed to do with all THAT drama????

    I've been tempted by Verio, but our insurance recently dropped OT from the formulary. I've been successful at getting them to continue to over her OT strips by saying that not having to enter her BG into the meter is a safety measure, particuarly when calculating insulin dosages. I couldn't play the same card with different strips.

    Not that we should have to play any cards at all!!!!

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  7. My experience would suggest you give the iBGStar a miss if you value your sanity. Quite happily gave me +0 to +33% readings across the range - and you would never know which is which. A consistent skew of readings I can deal with, but random variations on that scale would add a whole new spanner in the works.

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  8. I used Freestyle Lite and switched to BGStar: +20% readings.
    But now my A1C matches my average BGs.
    Verio is on par with BGStar, I would trust they both and you get a lower A1C "for free".

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  9. Ugh. Meters. Don't get me started! We use Freestyle strips in G's OmniPod PDM, as you did. When the new butterfly strips came out, I saw a jump in her A1C of .5, not a BIG deal, but I wondered what was up, as our card had not changed. The PDM when I compared it against Contour and OneTouch, ALWAYS read 15-20 points lower, consistently, and as BG rose, that gap widened. Just for giggles, I changed the code on her PDM to 17, and the PDM fell right in line with the Contour and OneTouch, which were always fairly close in their readings. For about 9 months now, we have used the butterfly strips, but code 17, not 16, in her PDM. And sure enough, her A1C came back down .5.

    I'm interested in your switch to the Tandem pump. Had a chance to play with one at the local CWD conference, looks cool.

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  10. We started using the VerioIQ meter TONIGHT. I love it, but hate adjusting to something new.

    It's SO EASY TO READ! It SHOOTS A BEAM OF LIGHT at the finger! The strips require SO LITTLE blood! It doesn't need batteries! It NOTICES PATTERNS (but won't really be so good at that because the school will be using a different meter.)

    And we're hauling around the pump meter remote, room to room..."sorry we're cheating on you. you're still good for something."

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  11. That makes sense. When I switched to the omnipod, my A1C went up. I blamed myself but I wasn't doing anything differently. I'll switch my 16 to 17 and see what happens...

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  12. I have a standing bet with my endocrinologist that I can guess my BG to which he never agrees (any of my endocrinologists in the past). I know I can guess it exactly especially with the different meters.

    I have a Medtronic Guardian CGMS and I have scientifically determined that the local weatherman is more accurate.

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