What's so great about Control IQ? Initial impression

Cat had been using a hybrid closed loop insulin pump, the Medtronic Minimed 670g, since January 2018. These hybrid closed-loop pumps (Medtronic 670g and the upcoming Tandem t:slim Control IQ) are different than traditional insulin pumps because they uses data from the Continuous Glucose Monitor (CGM) which in this picture is on her arm, and is checking her blood sugar every five minutes. The data from the CGM drives the amount of insulin delivery to the person wearing the pump.

Cat has been wearing the Medtronic 670g hybrid closed-loop pump with the Guardian 3 sensor and we have LOVED this pump. I've been using it since January 2019. It really keeps her (us) mostly steady unless we have an "oopsie" with carb counting, have a growth spurt, have extra activity, or have a bad pump site. (If you are not familiar, insulin is delivered subcutaneously through a small metal cannula that stays taped down to her skin for 2-3 days). The 670g pump increases or decreases the basal (background) insulin based on her CGM data. So if her blood sugar is trending high, the pump delivers more background insulin. If her blood sugar is trending low, the pump decreases or stops delivering the basal insulin for a while. Medtronic bases their micro-boluses (automatic basal delivery) based on the last 6 days of total daily insulin dosing.

The Tandem Control IQ promises to do this same action PLUS more. Not only does it adjust the basal rates based on the current blood sugar readings, it ALSO gives a correction bolus of insulin each hour if blood sugar is higher than target. So basically, if I mess up her carb counts, or forget to bolus, or if she's eating something that makes her BG go higher than normal for whatever reason, the pump will correct the high blood sugar IN ADDITION TO increasing her basal rates.

Control IQ uses the user-inputed correction factor (ISF) and then does 60% of this factor each hour if the BG is high. I have mostly left her high blood sugars alone because of this neato added feature on the pump. I think this will be a huge help at school. I did notice today that the Control IQ does not adjust basal rates when there is a certain amount of Insulin On Board (or Active Insulin).

Here's another weird thing I've noticed about Control IQ. If you have Active Insulin (Insulin on Board) from say, her dinner, sometimes it won't let me bolus her after dinner if she wants a dessert, even if I put in the carb count. I guess it's got some predictive features going on that I don't understand. Soooo....I guess the pump will correct her later if she starts going up from the Klondike bar? I always thought I needed to cover the carbs, no matter what.

Tandem also bases their basal insulin on the user settings. So if Cat's hourly basal rate is 1.0 units per hour, because that's what she would get on a traditional pump, that's what Control IQ uses. But it does adjust this up or down based on CGM data. Read the link I posted below for all of the deets about the ranges and targets for the Control IQ. I really like that the "Sleep" setting on the t:slim actually has a tighter range for nighttime.

The drawback to Control IQ is that IF your basal settings are not right, and IF your correction factor is not right, you will have some highs and lows. But of course, any pump is only as good as its user's settings. Also, the Control IQ sets the Active Insulin Time to 5 hours. You can't change this in Control IQ, nor can you change the target setting to anything below 110. On the 670g, Active Insulin Time was a huge factor in having success with Auto Mode. With ANY pump, it's important that you have your settings dialed in correctly.

It's a learning curve for sure, but I am really liking the no calibrations and no fingersticks AND the 10 day sensor. I'm looking forward to our 1 week phone conference with our trial coordinator to upload the data and discuss any changes...I'll keep you all posted!

First thing in the morning. You can see the red lines where basal insulin delivery was stopped to prevent a low blood sugar. The high "mountain" was corrected automatically by the pump. I didn't touch it. 

The diamond that is circled is our indicator that Control IQ is turned on. See how the top of the diamond is blue? That means that the pump is increasing the basal insulin because her CGM data says she is above range. 

When I look at the current status, because the diamond has a blue color on the top, I see that yes indeed her basal rate is increased. Typically at this time she gets 1.0 units of insulin per hour, but the pump has decided automatically that based on her blood sugar reading from her CGM, she actually needs MORE basal insulin, so it's giving her 1.54 per hour right now. Smart pump, trying to keep her in range! Also see the "last bolus" amount? I didn't give her that bolus...the pump did. 

Click here to read the ins and outs of the Control IQ system from Diatribe.

https://diatribe.org/tandem%E2%80%99s-control-iq-hybrid-closed-loop-algorithm-submitted-fda

Randomization Appointment today!

Today was another clinical trial appointment day for the Tandem t:slim pediatric Control IQ study. At this appointment they were doing the following: making sure that Cat had worn the Dexcom G6 for at least 11/14 days for the run-in phase (she wore it daily and our first Dex G6 sensor lasted the full 10 days, hooray!), doing a blood draw to test C-Peptide and A1C (norming for the national study), checking a fingerstick A1C, having us fill out several surveys, and then having the computer randomize our participation in the study.

We decided to drive up and drive back all in one day. It made for a LONG day, especially with the torrential rain and thunderstorms on the way home. Ugh. Next time we are getting a hotel.

The BIG QUESTION of the day: Would we be in the control group with our Medtronic 670g in manual mode with a Dexcom G6? Or would be be in the experimental group with the newest t:slim X2 with Control IQ? It was a nail-biter for a little while, for sure!

The blood draw could have been traumatic, but it ended up fine. Our super nice blood-draw guy (who I had met the week before at the TypeOneNation Summit) was very experienced with kids. However, Cat's veins didn't want to cooperate and they kept rolling away. And I made sure she was hydrated! We distracted her with visions of an iTunes gift card. She did great despite the amount of poking and prodding.

Next we filled out bunches of surveys. Surveys for the parents and for Cat. It was all on the computer. Also we did a fingerstick A1C. Yesterday was her regular endo appointment and her fingerstick A1C was 6.3%. Today at the clinic it was 6.6%. The differences in these A1C value serves as a reminder that A1C machines are not always accurate. The machine at your doctor's office, if it isn't calibrated right, may be off by a certain percentage. Regardless, I'll take it. Plus time in range is a new indicator for control, and she was 69% in range according to her Dexcom reports, with only 4% lows. That's AMAZING.  

After that, the endocrinologist and our clinical trial coordinator came in with the AWESOME NEWS! The computer randomization had placed us in the experimental group! We were going home with a new pump. WOOOHOOOO! Two other families were at the clinic that day for THEIR randomization appointments, and they were also in the experimental group. So we all went upstairs for training on the t:slim Control IQ.

The next hour or so we spent setting up our new pump, learning about Control IQ features, and making sure we knew how to work the pump properly. Since she was already using the Dexcom, it was easy to pair her existing sensor with the new pump. Now we can see her numbers RIGHT ON HER PUMP SCREEN. I was really missing that feature from the 670g. 

Here she is, all hooked up and ready to go! This t:slim is much cooler than the one that I had before I got my Medtronic 670g (I had the first generation). I will say I prefer changing the reservoir on the Medtronic 670g to loading the cartridge on the t:slim.  MUCH faster and easier (thank you Medtronic!) And the steps for loading the cartridge on the t:slim have apparently changed since the first gen model. There is "burping" of the cartridge (getting the excess air out) and now you fill the cartridge before you put it on the pump. That is NOT what we did back in the day when I was trained. But whatever! It's all good! 

It's only been a few hours, but our graph is pretty impressive. She had a pretty carb-heavy lunch right before we got hooked up and she's been pretty steady for the last few hours! Can't wait to see what the overnight looks like! I loaded her up on some carbs AND fat for dinner so we'll see how the pump does with that. Also, she had even MORE carbs for dessert (Klondike bar) after her carby fatty dinner of mozzarella sticks, corn and a fruit cup. But the pump wouldn't let us bolus for her Klondike bar. I mean she put in the carbs and her BG automatically populated, but it would not let her bolus. I guess it knows if it's enough insulin so I'm going to just go with it! If our settings are right, it should be all good. However, a pump is only as good as the settings that the user inputs. Soooo, we may have to do some tweaking in a week when we have a phone meeting with the trial coordinator. 

While the Medtronic 670g and the Tandem Control IQ have similar goals (hybrid closed loop system...insulin is delivered based on CGM data), there are some pretty significant differences in how these two pumps work. I'll do a deeper dive into those similarities and differences next time....but for now....STAY TUNED! 

(Diabetes Christmas today! Those of you with pumps know what I mean!)

Trying to be a Pancreas

(I wasn't planning on writing another post so soon after the one I wrote last night, but I felt the need to get this out there and this seemed like the easiest way to do it!)

Day 2 without our Guardian 3 sensor and Auto Mode: 

UGH. I didn't realize how amazing Auto Mode on the Medtronic 670g was keeping Cat's blood sugars. She typically has a flat line overnight and stays around 120. I know that within the Diabetes Online Community (DOC), that is a bigggggggg debate/source of contention...the fact that the 670g has a target of 120 and some people think this is too high and would rather set a target of 80 or 90 and blah blah blah, but I'm OK with us sitting at 120 all night, if we are steady and stable. Call me lazy, call me busy, call me both lazy and busy, but I really don't have time to be a pancreas x 2 ALL OF THE DAMN TIME. I have a full time job outside of the home. I have two other children. I have a dog and two cats. Plus I like to do stuff other than diabetes. Like scroll Facebook. And binge Netflix. So, the Medtronic 670g hybrid closed-loop system has really helped us not have to focus on diabetes as much, and it's been great. 

But yesterday and last night, she was using her regular basal rates and insulin sensitivity factor (ISF) along with the Dexcom. The basal rates are ones that I preset in her pump for use in Manual Mode. And clearly they needed adjusting. 

See that dip between 3 AM and 6AM? That's where I stumbled in and corrected her high blood sugar in the middle of the night. See how it went down, stayed kind of steady for a while, and then went back up? I think that both her ISF was not right nor were her basal rates. I did a major correction this morning and changed both her basal rates and her ISF. She's coming down slowly....I'll have to keep evaluating and adjusting throughout this week.

Please please please let us get in the experimental part of the clinical trial with Control IQ. I am not sure I can handle 4 months of having to be an active pancreas.

Dexcom Vs. Medtronic Guardian Sensor - An Anecdotal Report

For the past week, Cat has been wearing both the Dexcom Continuous Glucose Monitor IN ADDITION TO her Medtronic Guardian 3 sensor that communicates with the Minimed 670g insulin pump.

Since she's doing the "run-in" phase of the pediatric clinical trial for the Tandem t:slim Control-IQ system, I decided to have her wear both and see how they compared. Fortunately, Cat is a good sport and didn't mind wearing two sensors to satisfy her mom's curiosity. 

First, let me backtrack and say that we have had basically no issues with the Medtronic 670g pump. Cat has been wearing hers since January 2018 and I have been wearing mine since January 2019. I am completely happy with the system. We have amazing time-in-range and few incidences of hypoglycemia, which are the new indicators for diabetes control as opposed to the older standard of A1C.

However, I'm not brand-loyal when it comes to insulin pumps and CGMS. Sorry not sorry! I'm always looking for the newest gadget and the latest and greatest in diabetes tech gear. So trialing the Control IQ sounded like a really cool idea! (For what it's worth, I requested to be in the next generation Medtronic 780 pump trials, but the closest trial location was too far for me to drive on a monthly basis). I've used the Omnipod, the first generation Tandem t:slim and now the Medtronic 670g, so I have good experience with insulin pumps. But I will jump on the first ship that sails when it comes to the best technology for managing Type 1 Diabetes!

So ANYWAY, like I said, Cat has been wearing both sensors for the last week. And in my opinion.....

MEDTRONIC GUARDIAN sensors were hands down the most accurate. I'm sure some people will disagree. However, how many naysayers have worn both sensors simultaneously? And I do have data to back this up!

Part of the trial requires that we use their Accu-chek meter to test Cat's BG. So sometimes I used the same drop of blood and checked her BG with both the Contour NextLink 2.4 meter (that is linked to her pump) and the Accu-chek, the clinical trial meter. BOTH meters were always within 5 points of each other when I tested with the SAME drop of blood, so I'd say they were both very accurate. However, when I compared the two meters with the Medtronic Guardian sensor and the Dexcom sensor, the Dexcom sometimes read 20-30 points higher than the two meters AND the Guardian sensor.

I will say there were times that the two sensors were spot on, especially early on. But it seemed like the later in the week that we got, the more the Dex was reading a little higher than everything else. But...who's to say that they Dexcom isn't right and the other three devices were wrong? I mean, there is a margin for error with meters as well. So there's that. I definitely didn't worry that the Dex was reading a little higher at times...it was not so off that I felt the need to calibrate it. And I would rather it trend higher rather than lower, too.

I'll provide some pics of the device comparisons below. Some are close and some are not so close. 

This one was on the first day of the Medtronic sensor. VERY close. I was extremely excited. 

These were a little off, but still within range of each other. NBD. 

Here they were all different, but still within 30% of each other so it was fine. 

This one was a little concerning...that's quite a difference! See how both meters basically matched the 670g but the Dex was 20-30 points higher? We saw this MULTIPLE times over the course of the week. Still within normal, but it was weird how Dex ran high more often than not.  

As far as which we liked the best, I'd say hands-down Cat prefers the Dexcom. The insertion is simple, the taping is simple, the no-finger pricks, no calibrations....MAJOR pluses. Also, the Dexcom G6 has a 10 day wear, opposed to a 7 day wear with the Medtronic sensor. (I've seen many complaints in the Diabetes Online Community about the G6 not lasting the full 10 days, and maybe it won't, but we are at the end of day 8 with no issues so far so I'll call that a win). 

I will have to say I love those features too. But this is week 2 with the Dexcom + Medtronic 670 and I am going to let her wear JUST the Dexcom. And the Dex doesn't talk to her pump. And that means we will lose the "suspend before low" feature in Manual Mode as well as the Auto Mode program which adjusts her basal. We've had really good success with Auto Mode keeping her in range, and I'm going to hate to have to micromanage her pump in order to do the same job. It will be hard! But, I'll deal with it for the sake of science and research for Type 1 diabetes!

And so for this week (week 2), we are NOT wearing a Guardian Sensor with the 670g pump,  and we are using the Dex for boluses without fingersticks or calibrations. Unless we need to fingerstick for whatever reason (her symptoms don't match the number on the Dex, or it's a first day sensor), then the Dexcom will be our guide. 

Next week (Friday) we will find out if we are in the control group for the t:slim (where we will wear the Dex and her medtronic 670 with no Guardian sensor, like we are doing this week), OR in the experimental group (wearing Dex + t:slim with Control IQ). 

I think it's obvious which one we are hoping for....stay tuned!

Clinical Trial begins!

TWO SENSORS!

The clinical trial begins!

Cat was selected to participate in the pediatric trial for the Tandem t:slim Control IQ.  If you aren't aware, Control IQ will be Tandem's answer to a hybrid closed-loop insulin pump system. The Control IQ will not only stop the basal insulin with a predicted low blood sugar, as it does now with Basal IQ, but it's my understanding that Control IQ will auto-correct for high blood sugars, based on CGM data, which the 670g does not do. You can read more about Control IQ here. 

Since January 2018, Cat has been using the Medtronic 670g insulin pump with the Guardian 3 continuous glucose monitor sensors. We have been extremely happy with this system and have had great results with Auto Mode. The Medtronic sensors have been VERY accurate for us as well. I imagine that Control IQ would be similar, but not exactly the same as the hybrid closed-loop Medtronic 670g.

But....new tech is exciting to me, so when I was scrolling through clinical trials (which I do on occasion) and I found a study that was close enough so that Cat could participate, I was ECSTATIC. At first, we were waitlisted for the trial, but then the call came that she was IN! Cat doesn't mind new things either...when I explained what we would be doing, she was all like, "whatever". 

At our first visit, we had our screening appointment. A fingerstick A1C was taken, medical records were reviewed, current pump info was downloaded, and the study was explained in detail to us by the doctor. We signed all of the paperwork. Now, because we've only used the Guardian 3 sensors and not Dexcom for this last 1.5 years, we have to do what is called the "run-in" phase of the trial. All this means is that she has to wear a Dexcom for at least 11 out of the next 14 days. We got set up with the Dexcom G6 including downloading Share and Follow. During the run-in phase, we can still use our Guardian sensors and still use Auto Mode. SO, I thought this would be a great time to do a comparison of the two Continuous Glucose Monitoring Systems! 

I'll post my opinion + data regarding the comparison at the end of the two weeks, after we go back to to meet with the trial coordinator, as well as which part of the study we are randomized to: either the control or the experimental group. The control group wears their regular pump with a dexcom. The experimental group gets to wear the t:slim with the dex and Control IQ! Both groups eventually get to wear the t:slim with Control IQ in the last phase of the trial. 

Fingers crossed we get in the experimental group. I just think it will be really interesting to try the new technology before it's FDA approved! Plus, we are helping pave the way for children to be approved for this new technology when it comes out. 

So far, with today being day 2 of the Dexcom and day 1 of our new Guardian sensor, the numbers have been pretty accurate, and comparable to the fingersticks we've done as well. (Right at this moment Guardian is showing 129 straight arrow, and Dex is showing 127 straight arrow). 

Here is a pic from earlier: 

Cheers to new and improved diabetes technology! 

Inaugural Post

Hello! First post here!

Quick backstory...I'll write more in detail later on in other posts, but I'm a Type 1 diabetes mom to a Type 1 diabetes daughter.

I was diagnosed as an adult...age 38. My daughter, Cat, was diagnosed as a 7 year old, on Thanksgiving Day.

We are both Medtronic 670g pumpers, JDRF OneWalkers, and insulin-using superheros!!! I am gluten-free/lowish carb eating. Cat is free to eat whatever she wants as long as she covers it with insulin.

In the following blog posts, I'll share our stories, our day-to-day life experiences, recipes, Type 1 research information, other amazing Type 1 diabetes bloggers and podcasters, and whatever I feel like sharing.