Insulin Pump Smackdown: Revel vs 522

I’ve been wearing the newest pump available from Minimed in the U.S., the Revel, for almost four months now. Minimed made it available to me through their temporary loaner pump program, and have kindly allowed me to hang on to it while I decide whether the Revel, an upgrade from the Minimed 522 I currently own, is worth the $400 that it costs to upgrade via their Paradigm Pathway Program.

So I’ve been putting off sitting down and detailing how I like or don’t like the Revel for far too long now, knowing that as soon as I finally put my thoughts on paper, I will be forced to either pay for the upgrade or send the pump back.  But the time has come, my friends. And that brings me to the big questions: is the Minimed Revel, full of the promise of its new features, worth $400 more to me than the Minimed 522? Is the new pump an improvement, and, if so, what is the dollar value of the incremental improvement for me?

In thinking about this, there are several important angles to consider. Notably, I am coming from the position of having a Minimed pump already, and one that is jut one generation older to boot. However, there are several scenarios under which you might be considering the Revel*:

1. Having no insulin pump vs. getting the Minimed Revel

Get it. Get it get it get it. I know there are those who insist on staying away from pumps, appreciating the freedom of injections in that there is no machine tethered to their bodies, but I for one am a pump advocate. A pump devotee. The freedom of motion lost because of the machinery is far outweighed by the flexibility of schedule and insulin delivery gained. Plus, the ability to have a constant basal rate of insulin is hugely beneficial, both in terms of daily control and long-term mimicry of the natural pancreas.

But this is a review of the Revel, not a love letter to insulin pumps. So let me just say: if you don’t have a pump, and you’re being offered a Revel, the answer is yes. Definitely, certainly, soundly yes. (Okay, okay: for a less biased look at insulin pumping, see the American Diabetes Association’s discussion of insulin pumps.

2. Having no Continuous Glucose Monitor vs. getting the Minimed Revel

If you are in the unique situation of having an older insulin pump, and are being offered the Revel replete with its Continuous Glucose Monitor (CGM) system, the answer again is: get it get it get it. Having had a CGM now for about six months, I cannot express enough how helpful it is for daily care and my sanity. Even if the CGM is not always spot on, there is so much to be said for generally having an idea of where my blood sugar is going and where it has been. The trend analysis made possible by CGMs is a leap forward in diabetes care, and so if you are presented with the opportunity to get a CGM, grab it with both hands. And if your healthcare situation means you cannot afford a CGM, ask for it to be cheaper. Beg, cajole, plead, fight; we will see improvement and change if we as diabetics raise our collective voice and demand CGMs for better daily and long-term care, and prevention of costly complications.

3. Having another brand of insulin pump vs. getting the Minimed Revel

Here, unfortunately, I have little to say; I have been using a Minimed since I first started on the pump in 2005. Kaiser at the time offered the Minimed and the Animas pumps; I was told by my doctor most people chose the Minimed, as it had a few more features and was a bit smaller, but that the Animas was waterproof. Not being much of a waterbaby, I went with the Minimed. My first pump was the 515; I upgraded to the 522 early this year after my 515, sadly no longer under warranty, had an issue with its battery-compartment cap (more on those battery caps below).

So, I’ve been a Minimed user for all my insulin pumping years. I would, though, be very interested to hear from those of you on other pumps, especially if you’ve switched between brands– which is your favorite, and why?

4. Having another Minimed pump vs. getting the Minimed Revel

This is the bucket that I fit in. Note, of course, that if I didn’t have the CGM with my Minimed 522 before getting the Revel, I would fall under the “Having no CGM” category. But I had a CGM, and I had a Minimed. So, what makes this Minimed pump different, and is it worth the cost of upgrading?

Technically speaking, there are a number of new features that I detailed in a previous piece. Practically speaking, there are a few that stick out, and play into my decision about whether this pump should stay or go now:

a. New verbiage

Some of the menu options and message wordings on the Revel are different from those on my 522. For example, the menu item “PRIME” on my 522, which reveals options for restarting the insulin reservoir, has been relabeled “RESERVOIR + SET.” There are also many more confirmation screens on the Revel than the 522. Before rewinding the pump, for example, I have to confirm that the pump is indeed disconnected from my body.

I can see how this would be helpful for a lot of people, especially new pump users, or for people who don’t memorize step-wise procedures with ease. For me, though, this improvement has a null effect. I didn’t have a problem with the old wording; I learned it the first time around, and the new wording isn’t so different as to be fabulously clear. I thought the confirmation screens would be annoying, but they weren’t that bothersome– it just becomes another step in the pump preparation process.

So, for me, the new menu screens are neither a plus nor a minus. They are just a difference– notable, but overall uninteresting.

b. More graphs

On the 522, the CGM trend graphs were available for the last 3 hours of data, and the last 24 hours. As you can imagine, the level of detail available on a relatively small pump screen is not much to begin with, and many people find looking at 3 hours of data insufficient, but looking at 24 hours undecipherable. I’ve talked to a number of people, therefore, who love the Revel’s addition of the 6- and 12- hour views of CGM data, where it’s possible to get a little bit more perspective, without losing too much of the detail.

I find, though, that I almost exclusively use the 3-hour view. In fact, the only times I ever look at the other views is in the morning if I suspect something funny happened in the night, or to show off how good my numbers have been to my husband. Otherwise, the last 3 hours are all I need to see.

Now, that focus on recent data is not the same for all CGM users; I find there is a general division between people who like the CGM for the minute-by-minute data and those who like the CGM for the retrospective analysis. I am a minute-by-minute type; I’m aiming for good blood sugar now, and if I can maintain that at all instances of “now,” then the retrospective analysis should look fairly similar to the minute-by-minute data.

Because of my focus on the current scope, with small, incremental adjustments of insulin rates and boluses frequently throughout the day, the additional data views are nice, but not necessary for me. The 3-hour view is good enough for 98% of the time, and the 24-hour view is sufficient for the remaining 2%. So, again, this is a feature of the new Revel that many people appreciate, but for me, personally, I could take it or leave it.

c. More alert settings

With the CGM, both the Minimed 522 and the Revel allow you to set up alerts. So, if the CGM is reporting that your blood sugar is above a certain threshold, or below another threshold, the pump will beep in alarm. This is indeed a useful feature, and with the 522, there is only one set of thresholds– one for the HIGH alarm, and one for the LOW alarm. The Revel, however, allows multiple thresholds for both HIGH and LOW alarms according to the time of day.

Now, the alarms themselves are very useful, but I set my range fairly tight, such that I am alerted if my blood glucose value is reported below 60 or above 145 mg/dL. So, having multiple thresholds seems like a really good idea, and will be useful for many people, but in practice, for me, I already have the range set tightly enough that I don’t really need a second setting. With the Revel, I set up a second set of thresholds for the night– so that I am alerted below 70 or above 140– but that was mostly to try out the alternate thresholds. It’s useful to have that slightly tighter range available at night, but the added value is relatively small compared to the value of having any alarms at all.

d. Predictive alerts

In addition to having multiple thresholds for alarm settings, the Revel offers predictive alerts with the CGM. Based on the last set of glucose measures, the Revel can alert you when the current trend will put you above or below your HIGH or LOW threshold within a certain amount of time. So, if I’m 120 mg/dL, and I’ve moved up 30 points in the last twenty minutes, then the Revel is set to alert me that it expects me to pass the HIGH threshold I have set at 145 mg/dL in the next 15 minutes. Additionally, the Revel will display arrows reflecting the rate of change– one arrow, either up or down, if blood glucose values have changed more than 10 mg/dL in the last 10 minutes, and two arrows for more than 20 mg/dL in the last 10 minutes.

If you’re not very attentive to the CGM’s readings, or don’t have an easy time determining how fast your blood sugar is changing, the predictive alerts are very useful, and will make it much easier to keep on top of your blood sugar as it varies. As I’ve mentioned, however, I love the CGM for the recent, short-term data. So I’m constantly checking it, and usually more or less aware of where it’s been and where it’s headed. And, I am pretty good at calculating the slope of the trend line– so if I was 100 twenty minutes ago, and 110 ten minutes ago, and 117 five minutes ago, I know I am going up at more than 5 points per five minutes, and the rate is increasing, not leveling out, so chances are I am going up quickly.

So, for me, personally, the predictive alerts are often helpful, especially for those times when I don’t happen to be playing close attention, or when my blood sugar is going up or down more rapidly than I expect. But, can I get by reasonably well without them? Probably. I’m the kind of person who likes a bit of calculation and math, though– if you’re not, I imagine predictive alerts are a huge help and relief.

e. Smaller insulin increments

One of the features I was most excited about with the new Revel is the smaller minimum basal rate amount. Instead of the minimal rate of 0.05 units per hour that the 522 offers, the Revel can deliver as little as 0.025 an hour, which is a big boon for kids and insulin-sensitive diabetics. For me, it’s the perfect point between “I want to turn off the basal rate entirely for an hour,” and “I want a low basal rate for an hour.” It is the happy middle spot– “I want just a little, tiny bit of insulin, not enough to make my blood sugar decrease, but more than nothing”– that, the 522 lacks.

The smaller minimum rate is also available with boluses, allowing boluses as small as 0.025 units. And, along with the smaller bolus values, there is more precision visible while bolusing; so, when the Revel shows how much insulin has been delivered, it reports the value not just to the tenth of a unit, but down to the 0.025 level. I found this very useful for those times when I start a bolus and change my mind halfway through about how much I want to deliver. It was much easier to stop immediately, and then set up a new bolus to make up the difference between how much I had just delivered and how much I wanted to deliver total, as I didn’t have to worry that I’d be a whole tenth of a unit off in either direction.

One of the problems with changing and upgrading products is it makes me as a consumer more aware  of what’s still missing. In other words, the Revel still has a few of the same shortcomings that my 522 has:

* Low screen resolution: The computer monitor I’m typing this on has over two million pixels with which to present crisp and clear data. The pump screen? Maybe 10,000, if I’m being very generous (estimating somewhere in the 160×60 range). Why is the Minimed screen so low-resolution, with such little contrast between the background screen color and the text color, even when the backlight is on?  I would guess cost is an issue; new, cutting edge screens are more expensive, and would require different technology to run. But, come on, Minimed, let’s get there– can we at least aim for smart-phone clarity rather than disposable-phone clarity?

* No volume control: The myriad alarms on the pump are indicated by different series of beeps and buzzes, and over the last five years, I have gotten pretty familiar with what different alarm sounds mean on my pump. However, there is no volume control; I can’t silence them in meetings (which, yes, can be embarrassing), or turn them up at night (when a missed alarm means I wake up at 40 instead of 60). So, having some control over volume levels would be really nice.

* Weird backlight noise: This is minor, and I hadn’t even noticed it until recently, but when the backlight of the pump is on, there is a weird high-pitched noise that can be heard up close. This isn’t bothersome under normal circumstances at all, but it strikes me as strange and mildly worrisome. Consumer electronics don’t do that; what is it about insulin pumps that does?

* Half-hour time increments: The smallest time increment for a temporary basal or dual-wave bolus is one half hour. Why? Why not give me fifteen minutes? Sometimes I just want more granularity in the time increments. And, of course, my default is to think, “Boy, fifteen minute increments would be very nice,” but really I don’t see why I can’t just program in the time down to the minute. That would be inconvenient with just up- and down-arrows, but who says there have to be only two up- and down-arrows anyway? Let’s see some innovation, so that I can set a temporary basal rate for 22 minutes, if I want to!

* That pesky battery cap: Maybe it’s just me, but the battery cap on the Minimed pumps is a piece of work. Silly, weak little piece of plastic that wears away ever so slightly every time I open or shut it to change the battery. I’ve tried opening it with a quarter, as the Minimed representatives suggest, but that wreaks havoc on the small plastic indentation. A screwdriver is even worse. For now, I use the back-end of a pair of tweezers, and I make sure not to close the battery compartment very tightly, leaving the cap a full turn from a snug closure. I’ve had two caps reach the point where the plastic is stripped away, such that I cannot get sufficient leverage to turn the cap and open or close the battery compartment. This seems like a severe design flaw, and one that should be relatively easy to fix– just make the cap out of a more durable material. But, like I said, maybe it’s just me; I don’t think I’m doing anything strangely when I open or close the device, but I haven’t heard others complain about this problem, either.

Those problems notwithstanding, I like the Revel overall. It works reliably, is generally easy to use, and, as I mentioned above, is a zillion times better than no pump or no CGM. But my fork in the road is very particular: is it $400 better than the Minimed 522 I already own? Are the new features worth $400 to me?

That’s a bit of a loaded question, of course. What is $400 worth to me? Two or three years ago, when I happened to be more cash-rich and everyone seemed to believe that we would all become millionaires if we just put enough money into emerging market funds, I would have said, “Of course! $400? That’s nothing! I’ll upgrade today.” But the markets have gone downhill, and what’s more, I’ve taken a job that means “cash-rich” is a dream state.

I would get more graphs, smaller insulin increments. That’s nice. But is it nice enough? To be honest? I’m going to have to go with “no.” It’s nice, but not all that different than my 522. Maybe if I really used the 6- and 12- hour graphs.  Or if I couldn’t easily tell which direction the CGM was indicating my blood sugar was heading. Or if I wasn’t able to get by without the 0.025 unit increments. But as it stands, I felt just as happy with my old pump as I feel with this one. If I didn’t know there were these new features available, I wouldn’t miss them more than I do the set of things the Revel itself doesn’t have.

Clearly, though, that’s just me– depending on how much $400 is worth to you, and how much you think you would like each of the new features, you might very well make a different decision in the same position.

In the end, though, I must say goodbye. So long, little fellow– travel safely back to the Minimed offices! It’s been nice getting to know you, but you’re a bit too pricey a ride for a cash-poor girl like me. Maybe next time, but until then, I’ll stick with my Minimed 522, far from the cutting-edge as it may be. I hope I don’t miss you too much!

*Disclaimer: I am a patient reviewing this product, not a doctor or medical professional.  The opinions  expressed here are my own and not those of ASweetLife or its editors, and this is intended for informational purposes only. You should not make any changes in your insulin and blood sugar monitoring regimen based on this review.  If you think an insulin pump or continuous glucose monitor might be right for you, consult your physician.

Karmel Allison

Karmel was born in Southern California, diagnosed with Type 1 Diabetes at the age of nine, and educated at UC Berkeley. Karmel now lives in San Diego with her husband, where she is loving the sunshine, working in computational biology at the University of California, San Diego, and learning to use the active voice when talking about her diabetes.

Karmel Allison

Karmel was born in Southern California, diagnosed with Type 1 Diabetes at the age of nine, and educated at UC Berkeley. Karmel now lives in San Diego with her husband, where she is loving the sunshine, working in computational biology at the University of California, San Diego, and learning to use the active voice when talking about her diabetes.