Six Weeks: More Thoughts on Control IQ

This is not a “How-To” for Control IQ. I haven’t completely figured it out and for sure I can’t provide much guidance for other people using the system. I think that each of us will have to find a way to succeed (or fail?) with this algorithm and what works for me might not work for you. In fact my road to success probably won’t work for you. Actually at the moment it is not completely working for me. But it is getting better.

I finished my February 13 blogpost with this comment: “Control IQ is a step forward for me. I don’t love it yet. But I think I will.”

A month later I would say something similar. I don’t love Control IQ and occasionally wonder if I should have stayed with Basal IQ. But I am still committed to figuring this out. Even on my worst days I am not tempted to turn off Control IQ because the benefits of 24-hour protection from lows and better-than-before overnights are addicting.

Here are some things that I have learned in the last couple of weeks. Some people may disagree with my analysis of how the algorithm works and I look forward to feedback. For sure I am not quoting the Control IQ User Manual.

*** Use social media and Facebook to learn what is working for other Tandem Control IQ users. Don’t become paralyzed or discouraged when you seen flatline graphs and average BG levels of 100 from other Control IQ-ers. I don’t seem to be able to average BG’s in the 90’s or low 100’s because my insulin keeps suspending with resulting highs later on. But I am willing to learn from others who are succeeding and even from those who are struggling.

*** Consider turning to “professionals” to help to dial in settings. (Every blogger has to give the disclaimer that you shouldn’t do anything without talking to your doctor.) I am such a self-manager of my diabetes that it would never dawn on me to make a special endo or CDE appointment to talk about Control IQ. But I will be very open to suggestions from my doctor when I see her in May. Frankly right now I don’t think that many medical professionals have enough experience with Control IQ to adequately analyze our settings but I know that they will be learning in the next months just as we are learning. If I wanted to consult with someone experienced with hybrid-closed loop systems such as Looping, OpenAPS, Control IQ, and the 670G, I would probably contact Integrated Diabetes Services.

 *** Figure out your goals but don’t be afraid to tweak them as you move farther into this semi-automated insulin delivery system. Consider changing your target range so that you “succeed” within the parameters of Control IQ. Prior to Control IQ, I used a target range of 70-150 and stayed in that range a good percentage of the time. Every week that I used Control IQ I saw my statistics for that range get worse. For me that was discouraging not motivating. My endocrinologist has always encouraged me to use 70-180 and I have switched to that target for a while to boost my mental health. Interestingly my average BG between the two range choices is not different because I am doing the same things to have acceptable BG numbers. But I feel happier seeing a higher time in range in Dexcom Clarity reports. BTW I still use 150 as the high alert on the pump.

*** I think that one characteristic of “ideal” Control IQ settings is the avoidance of long suspensions of insulin. When I say “long”, I mean one hour or more.  Unfortunately I see such suspensions almost every day. Whenever I go 1-2 hours without insulin, I always go high because I just can’t be without insulin that long. The problem is that these suspensions don’t happen at the same time or in the same circumstances each day. My solution has been to learn strategies to trick Control IQ into giving me more insulin during and after these suspensions. I first tried manual boluses but that often just prompted Control IQ to suspend insulin again. So thanks to a Facebook friend, I learned about entering “fake carbs” so that Control IQ thinks that the bolus will be matched by carbs. With fake carbs, Control IQ doesn’t automatically suspend or reduce insulin as it might with a manual bolus because it expects carbs to raise your BG level. The downside of this is that your average daily carbs statistic becomes meaningless.

*** Don’t eat. Okay, that is an exaggeration…. But meal bolusing is different for me under Control IQ than previously with Basal IQ or regular pumping. In general I have to analyze what Control IQ has been doing for the last hour or two to decide how much to bolus, how far ahead to pre-bolus, and whether I need to “trick” Control IQ by adding fake carbs to the real carbs. Once again if the meal bolus is preceded by a long insulin suspension, I need the bolus to be larger than if it was preceded by my normal basal rates. I have to be careful with pre-bolusing because Control IQ will likely suspend insulin if it sees my BG dropping too low before eating. Fortunately unlike Basal IQ, Control IQ does not suspend extended boluses and that is a tool I am sometimes using to smooth the action of mealtime insulin. 

*** Simplify your pump settings as you work to figure out optimal Control IQ settings. I initially started Control IQ with my “Normal” settings and the results were not great. Then I created a new profile titled “Aggressive” and it was indeed too aggressive. I didn’t have much insight into what settings were working and which weren’t. So I created a new profile titled “One Rate.” Same basal rate, correction factor, and carb ratio for 24 hours a day. It is very similar to my pre-Control IQ settings although the carb ratio is slightly more aggressive. I have since added one more time period to that profile so technically it should now be “Two Rates.” IMO it is a good idea to use new profiles as you experiment with settings. Eventually I’ll delete most of the extra profiles.

*** Use your experience to help others in the diabetes community. It takes a village to figure out Control IQ and everything related to diabetes.

*** Sell your stock in companies that manufacture glucose tabs. These automated insulin systems are really good at reducing lows. At the same time continue to always have fast-acting carbs available. Control IQ is good, but it’s not a cure.

Summary:  My main goal with Control IQ is to have reasonably good numbers with less effort. My average blood sugar has risen with Control IQ and I expected that. One reason is fewer lows. I rarely see the 70’s and almost never the 60’s or below. The other reason is that I spend a lot of time between 100 and 125 and not much time in the 80’s. I am OK with that. I continue to use Sleep Mode 24/7 with a target range of 110-120. Less effort has not completely materialized and I am still micromanaging. But increasingly I am having longer periods of time when I don’t glance at my pump and just trust the algorithm to do the work. As long as I compensate for long insulin suspensions, that strategy is starting to show some success.

So maybe it is getting easier.