Originally published May 29, 2018.
When Medtronic’s MiniMed 670G hit the market in late 2016, it was heralded as a milestone. While insulin pumps come and go, and CGMs (continuous glucose monitors) change incrementally, this was the first diabetes tech marketed as the next “real” big thing: a hybrid closed-loop system that was essentially the first iteration of an Artificial Pancreas. For those whose actual pancreas doesn’t function as intended, the appeal of this automated pump+CGM product seemed obvious and potentially life-changing.
Two years after its FDA approval, it seems to safe to say that the 670G has indeed been life-changing. But in what ways? And what might a potential user want to know about how it works on a daily basis IRL?
We turned to three 670G users to hear their stories. They also share some awesome specific Tips for Best Use, listed below.
Relief At Last
Kristin Gates is 22 years old. She’s a photographer who lives in Queens, NY, and works as a photo editor at a daily newspaper. She was diagnosed with type 1 diabetes eight years ago and vividly remembers when the 670G became available.
“I was at the MoMA on a class trip at the time,” she says. “I got an alert on my phone and actually cried in the bathroom.”
She says she knows that moment was a little dramatic, but there’s no shame in that. “I really just needed something to come along and help me,” Gates said. “Being in high school and then going to college I had lost track of my health.”
Gates describes her A1C levels being in the high 9 range. She was “done with diabetes,” eating whatever she wanted and going days without checking sugars. A dangerous combination of doubt, frustration, and fatigue was winning. “I was still in denial,” she says. “But the past two years I got my act together. I started to focus on lowering my sugars, but I still felt they were out of whack. I held onto the hope of having the 670G, knowing it would get easier as the technology advanced.”
Gates’s first pump was the Animas Ping, which she loved. After that she struggled with the Animas Vibe pump with Dexcom CGM for a while before switching over to the Medtronic 530G. She describes feeling that the interface was off for her and feeling generally out of control of her sugars.
Gates has now had the new 670G device for just over a month and has been wearing a sensor the entire time, which is new for her. “I don’t think I’ll ever stop,” she says. “Body image issues aside, I was always pissed at the old sensors because of how inaccurate they were. This one is never off by more than 20 to 30 points.”
Gates has always struggled with sensors and has an extreme aversion to putting them on. She’s worked around the problem by having her boyfriend apply the 670G sensor. “Having someone else put it on me took a huge burden off,” she says. “And I’ve noticed that when I have the sensor off even for the warm-up period, I feel out of control and can’t imagine how I lived my life without one for the past eight years.”
Having used two other pumps herself and seen people interacting and using the Omnipod as well, Gates says there’s no comparison. The 670G system, she says, will humbly tell you to get your act together.
“The user experience is big for me, so I love being able to quickly scroll through menu options, having the screen be bigger, and in color (I like to compare it to the original Game Boy versus the Game Boy color),” she says. “I like the option of having it shut off at night when I go low and it’s really good about yelling at you when you’re entering the high areas.”
The system will also exit Auto Mode when a user has been high for an extended period of time or hasn’t checked his or her blood sugars. The blend of autonomy and oversight it offers appeals to Gates and other users we spoke with.
Gates does caution that the 670G, while revolutionary, can’t fix it all. “I think my biggest wake-up call was when I realized it isn’t a cure,” she says. “It can’t keep those pesky foods from spiking me through the roof, and it doesn’t have the power of an automatic correction bolus.”
Like many New Yorkers, Gates is constantly on the go. She might be moving through the city, running around at work, or sitting in meetings. In all cases she feels secure that the 670G will keep up with her. “My biggest fear is getting stuck down in the subway and having a low and not having glucose,” she says. “(This system) has stopped almost every impending low and has made me realize the changes that need to be made in my diet. As a first time CGM user, I really am learning what spikes my blood sugar and how long it will take me to really come down from the spike. My highs have decreased by a significant amount too.”
A Useful Help Line
As a diabetes blogger and a longtime Medtronic fan who volunteers as a company ambassador, Cara Richardson is something of a veteran of the diabetes tech world. Richardson lives in Nashville and was diagnosed with type 1 when she was four.
Medtronic describes their patient ambassadors as a group of real customers who make themselves available for honest one-on-one conversation with people about life with diabetes. Richardson says she values the chance to do outreach this way and share her experience, especially around diabetes tech. She adds that Medtronic even maintains a website where people can find ambassadors with similar interests or lifestyles as them, a valuable tool for those considering the MiniMed.
Richardson, now 36, started using the 670G in February. So far she’s been pleased with her results. “I’ve noticed way less low blood sugars, and with that has come the return of some of my low symptoms that had been missing in past years,” she says. “The best part is that when the 670G is in Auto Mode, it consistently directs you to a blood sugar of 120, meaning that I can sleep through the night with no CGM alarms about 98 percent of the time.”
Years of alarms at night and lost hours of sleep are a common and yet still under-recognized consequence of life with diabetes. “I couldn’t believe how great it was to have those nights of solid sleep and now I’m a bit spoiled,” says Richardson.
One of the big features of the 670G is its “Suspend on Low” and “Suspend Before Low” function. Both functions are only accessible in Manual Mode. They cannot be controlled in Auto Mode, a limitation users have reported frustration with. Richardson said the contradiction seemed strange to her until she realized that in Auto Mode the pump was doing those things anyways. “It will stop your basal if you’re dropping and restart when your blood sugar begins to rise,” she says. “You also can’t use the dual and square wave boluses in Auto Mode. I thought this would be a problem for me, but so far it has not been. I am having good results by letting the system do its job.
“The first few weeks in Auto Mode are tough if you’re a bit of a control freak about your blood sugars like I am,” adds Richardson. “Your blood sugar will run a bit higher than some people may like because the system is getting to know you and your body, and for safety reasons, running a bit high is better than being low all the time. I’m blessed because I knew a few people already on the 670G and they had warned me about this. There was also some changing of my insulin-to-carb ratios, as the Auto Mode works a bit differently. If your blood sugars aren’t doing what you want them to do, be sure to get with your health care team to talk about how to fine tune your treatments to get the best results from the 670G.”
Richardson also cautions that even long-time Medtronic users may be initially flummoxed by the 670G’s menu, which is set up differently than previous Medtronic pumps. Richardson says it took her a bit of manual reading and pump exploration to figure things out. “It’s a good warning for folks coming from an older Medtronic pump,” she said.
“Don’t be afraid to call the help line,” she says. “I have received some amazing customer service from the Medtronic help line. It’s 24 hours, and everyone I’ve spoken with has been great. They even have a team that deals specifically with the 670G, so they are more specialized and have a better knowledge base if you call in with questions or concerns.
“Having great blood sugars, and not hearing alarms all the time, makes my life so much better. Sure, there are still bad days and good days. Diabetes isn’t ‘fixed’ by this technology. But it’s nice to have a good night’s sleep, to be able to work through the day without worrying so much about when I’m going to be able to grab a snack, or if my blood sugar is too high.”
Richardson began pumping 12 years ago and has consistently been on Medtronic pumps since then. She was the first person in her state to get approved by her health insurer for a Medtronic CGM system. All of this gives her a substantial window into the improvements, and shortcomings, of the MiniMed 670G over prior Medtronic iterations.
“The most notable (improvement) for me being the alarm volume (it actually wakes me up if it goes off!) and the water-resistant status. I’ve yet to try the water resistant part out, but summer is coming, and I can’t wait to have the chance!”
Defining Your Own Experience
For Joanne Welsh, who works as an IT project manager at Children’s Hospital in Philadelphia, the early days with the 670G were the hardest. But once she mastered sensor placement, she found the device really began to deliver on its promises.
The Suspend Lows features and the prospect of the micro-bolus were appealing to Welsh, so she didn’t hesitate to transition to the 670G when she gained access to the device through Medtronic’s early access program. The next part of her story wasn’t so positive.
“The adjustment period to it was really pretty tough,” Welsh says. “There was this whole calibration sequence and blood glucose entry sequence that always, especially when you’re trying to work in auto mode, seemed so unreasonable. I kept thinking, I just gave you that, why are you asking me for this again? That kind of thing. And if you aren’t judicious about your calibrations and you don’t limit it to three times a day, the machine gets confused. It’ll ask you for more blood glucose results and more calibrations and pretty soon it’ll just give up and tell you that your sensor failed.”
At first, Welsh struggled to get a sensor to last for four days. MiniMed sensors are supposed to last for seven days.
The prescribed sensor location for the sensor is the abdomen, somewhere between the ribs and the naval. Welsh, though, found that to be the least reliable spot for matching up sensor glucose readings and her body’s actual glucose levels.
She moved the sensor to her upper leg and had better luck. But she still wasn’t getting near seven days of sensor life. Her next move was to the back of the upper arm.
“That worked really well and I also started getting longer life out of sensors — six to seven days,” she says. “Then I thought, well, summer time is coming, you’re going to wear sleeveless top or bathing suit, maybe you don’t want it on your arm. So I tried around the love handles, between the abdomen and the back. It’s not the most comfortable, but usually it’s okay. And I do get six to seven days there.”
The idea of a closed-loop system is intimidating for many, who fear being frozen out of the equation, so to speak. The system is meant to read your sugars and automatically release insulin accordingly, leaving the user more or less along for the ride. For many who have spent years fine-tuning their health practices, relinquishing control is a painful process. Very true for Welsh, who was diagnosed when she was 14 after a school-administered urine test came back positive, and has had type 1 for more than 50 years now.
“When you have any of those other Medtronic pumps, you’re trying to boss that thing around,” she says. “You’re a control freak. You’re doing all the things you have to do to get yourself in range. But with the 670G, if you want to be on Auto Mode, you have to let all that go. It gets to be boss.”
Therefore Welsh stresses the importance of training and trust with the system. “You have to insist on training,” she says. Welsh received training from a Medtronic employee and her CDE with the device. And she has watched other people really struggle to figure the system out.
“This is not for the novice,” she adds. “You have to trust that the machine is going to do what it needs to do. Also, if you’re a person who’s been skating around getting your A1c under 6, it’s probably never going to happen with the system. Patients, they want that low number and they walk around nearly hypoglycemic just to get it. That number is just not important enough to me to live like that.”
Of course having a “good number” according to the medical community is sometimes different than being healthy. Welsh has two healthy grown children and two infant grandchildren who so far have normal blood sugar levels. “I’m kind of keeping an eye on everyone,” she says. “Just hoping that they don’t start with this either. I’ve coped with diabetes enough. I don’t want anybody else to.”
As for her future with the 670G, while she likes the system for now, Welsh wants to keep pushing and exploring. “I think I’m going to continue with the 670G until I’m out of warranty,” she says. “Then I’m going to see what else is out there. I’ve been reading about what some folks are doing on their own. Making their own closed loops. Modifying a pump. Building their own little circuits and things. I’m not interesting in making a real full-time job out of building myself a system. If somebody wants to do it for me, then we’ll talk.”
With increasingly complex diabetes tech, sometimes the simplest things can make all the difference. Our users described several important product characteristics and workarounds that have helped them best utilize the 670G. Here’s what to think about if you’re a new 670G user or considering taking the plunge:
1. Enjoy easy battery access. Note that unlike many pumps, the 670G’s clip holster has a designated tab to open the battery compartment. No more nickels needed to screw off the battery caps!
2. Sleep soundly. Auto Mode is a big seller on the more-sleep front. By redirecting levels back to norms, it seems to consistently help users achieve more restful, alarm-free nights. But our users say to think twice about putting a new sensor on before bed, as the calibration kinks are quite likely to mess with a peaceful night’s sleep.
3. Monitor sensor life. The 670G sensors are marketed to last seven days. That rarely seems to be the case for our users. They report inconsistent accuracy the first day as the sensor adjusts. Days two through four or five seem to run pretty smoothly with calibrations lasting up to 12 hours (make sure to calibrate when your levels are generally steady for you). By day six, calibrations become much more frequent and sometimes the device calls for a sensor change.
4. Beware alert overload. We love our alerts, reminders, and data. But sometimes enough is enough. The 670G has a vast array of alarms: high alerts, low alerts, predicted low alerts, rising quickly, falling quickly. Our users report learning pretty quickly that all those alarms can be too much. They’re there for a reason, sure, but spend some time figuring out what’s essential for your diabetes control versus what’s just another beep distracting you from living your life.
5. Keep pre-bolusing. Our users said that if you pre-bolused on your old pump, when switching to the 670G, you should continue that practice. The 670G reads your body and reacts accordingly, but the insulin it uses needs the same head start any other pump would.
6. Consider carb counts closely. Carb counting isn’t new to most people with diabetes, but people often tend to guess more than they admit to themselves. This can be an issue with 670G. The system works with what information you give it. If your carb counts are way off or you forget to bolus, the system does what it can, but can only do so much.
7. Call for help. This is arguably the most complex insulin system available to date. Even a Medtronic ambassador we spoke with had a bit of a tough time navigating the new Medtronic menus at first. Manuals are great, but they may not be enough. If they aren’t, don’t hesitate to call the Medtronic help line, which operates 24/7 and has a team well-versed on 670G-specific questions.
Greg Brown is a freelance writer living in western Maine. He has written for Consumer Reports Magazine, Consumer Reports Online, The New York Times, and the Chicago Tribune, among other publications. He can be found online at www.yellowbarncreative.com.