Basal Testing


I was curious how often you all test your basal rates… I haven’t had to very often, but recently I’ve been having evening lows so it was suggested by my Dr that I do the series of basal tests.


I think basal testing is useful when you are starting out, but for me, I find if I experience a change in my numbers which is a pattern, I will tweak the basal dose for the period two hours before the problem time and that usually does the trick.


I usually leave well enough alone as long as my blood sugars are satisfactory If I get unusually high's or low's then I'll review my basals & tweek if necessary. I live in AZ. and we are having higher than normal temps. Today it was 75 and sunny which is wonderful for my usual walk in the morning which is always a plus for my blood sugars.


I generally do informal basal testing whenever something is repeatedly "off".
There's formal basal testing, which is the "don't eat for 6 hours leading up to, and not at all during and don't get any exercise and hold still and don't breathe" version (of which I am being overly dramatic, and I understand the point full well, but since nothing else I do is held to such rigorous standards I don't think its reasonable that this should be either).

I go with the much more casual "Don't eat for a few hours as is convenient and see how it plays out" version, and then make small changes as needed. Sure, its not as accurate as the other way, but its a lot easier to fit in and breaking it down into smaller chunks of time means I can stand to repeat it more often.

For years I avoided doing basal testing because it seemed so intimidating, but breaking it down into a smaller pieces and fitting in when convenient makes it way more tolerable for me and therefor easier to do and get information out of. Potentially I have meetings every Tuesday afternoon and Thursday mornings right now, so I regularly use those days to do any basal testing because I'm probably not eating anyway- might as well hold out another hour or two and see what my BG looks like.


I am glad that they are others who don’t do basal testing as much as they say to you should. I too, wait till I see a pattern of some kind. I know John Walsh says 1 basal test a week, which is kind of unrealistic, especially if you have a busy lifestyle. When my average increases or I get alot of highs I start making changes.


I definitely ought to make adjustments every 3 months, but I often dont. Kinda depends how dramatic the shift is, sometimes it changes so dramatically that I start having problems and need to adjust right away. If I wait that long, then I might have put myself into a bad position because it takes me several weeks, at least to get the kinks worked out. Earlier this year things got quite unsafe. Should have adjusted much sooner. I regretted my laziness.


I think everyone should know HOW to test their basal. And starting off on a pump, this should be done.
But after that, just watch for patterns.
I think a lot of the basal testing mentality is a carryover from before the CGM era. With Dexcom Clarity, XDRIP, etc. these programs will show you at a glance what your 1,3,7,14,30,90 day patterns are. Super easy to see where you need a change!


I must say I do it more often than most. And there have been a few times over the years, where I just do a clean sweep and start over. I find that I change things more often with CGM reports and sometimes that can mess things up. So last month I just set one basal rate for the whole day and did a few days of testing. I also find going 12 hours without eating doable. And than the frustration can set in when .6 is not enough but .7 is too much. And days later with multiple days of testing come up with .675. The disease never plays fair or by the rules and can be very frustrating when you get two days that show the same pattern and than the next two test days show something different. But I keep plugging away and hope I get it right. I am always amazed at the people who can go years without changing things.


I think the old fashioned formal basal testing protocol is a good exercise, especailly for people new to pumping. As others have said, with paying attention to the CGM trace and using reports like the Dexcom Clarity 14-day AGP, it’s relatively easy to make rational changes to basal rates.

Diabetes control is a moving target. I think it’s ideal to be making changes to basal rates, insulin sensitivity, and insulin to carb ratios relatively frequently. I make changes at least a few times per month.