Basal and ratio testing...does it really work?

How reliable is basal testing and testing of ratios?

Especially for those of you with fantastic control, do you do basal tests and carb/correction ratio tests? Are they useful and accurate?

Since getting my Dexcom I've been working on getting my overnight basal rates to be as good as possible. It's gotten to the point where they were pretty good, but there is still a fiar bit of variability compared to what you are supposed to get when your basal rates are "set right" according to John Walsh and others.

The night before last I exercised in the evening and then set a -10% basal rate for 8 hours overnight and completely flatlined. I mean, I was around 4.5 (80) for the ENTIRE NIGHT! And then I skipped breakfast and continued to flatline until NOON! I was so impressed. Thought I had it nailed. In fact, the entire 24 hours was pretty awesome, although I did have to eat a fair number of carbs later in the day to avoid lows.

So I did exactly the same thing last night - same exercise, same meal, same insulin reduction, same timing - and my dinner bolus (which I ate after exercising both nights) failed to bring me down, so I spent most of the night around 9.0-9.5 (162-171), and then around 4:00 AM I started drifting down quite a bit until I woke up at 6.4 (117) at about 7:30.

So that is a 0 mmol/L drop one night and a 2.5-3 mmol/L (45-54 mg/dl) drop the next with literally exactly the same routine. I assume that, had my dinner bolus brought me down properly after eating last night I would have ended up going low sometime before I woke up this morning.

I've been working on this overnight basal rate for two months now. So do I continue working on my overnight basal rates? Why is it that some nights (maybe 50%) I am practically dead flat overnight and feel like I have it, while the other 50% of the time I go high or low? Do any of the people here who have great control experience this? I'm not talking about a pattern, like a few days of going high/low, I'm talking about having four nighsts of a week flat, and the other three nights not flat, but not consequitive non-flat nights.

And since overnight is the most simple time in terms of inputs and outputs, of course this has me wondering about the rest of the day.

This is not a post borne of frustration - I am doing great with the Dexcom, it has had an incredibly positive impact on my ability to avoid extreme highs and lows. I've been able to stay within 4-10 (70-180 mg/dl) for 70% or more of the time. I'm just wondering, in my quest to improve my control, if I'm putting my time and energy into the right places.

Hey Jen. Glad the Dexcom is a positive up for you. Way to go!

I used to basal test all the time. Then I realized it was pointless for me. I find soooo many variables--what I ate, who cooked the food, the weather, my stress levels and moods. Is the pump working correctly? Is the insulin OK? I try to be perfect, but it is not possible for me.

Oddly, overnight is the hardest time for me. I strive to not be low overnight, and of course, not be too high. But the variables all play into it--Spring is almost here and I have already started having weather problems,

As hard as I have tried, I have never been able to be a true long term flatliner. Would I like to? Oh yes. It would truly be like not being diabetic.

I wouldn't say I have great control, pretty good probably, but I would like it to be much better and more "normal feeling". I haven't felt normal since being on insulin.

I think I have too much variability to ever have a set basal rate at various times, my cde agreed. I go through periods of flatness and then bounce around a lot, seems to just be the nature of the beast for me. I'm constantly doing temp rates and corrections etc. Fortunately for me, so far, being able to shut off the basal to 0% helps me treat the lows. I shut off for 15-30 minutes usually and treat with glucose as well if needed, sometimes not. I also lower but not to zero at times if a low is coming on but 0% seems to be more effective if I'm active. It has an immediate effect for me and I stabilize quickly most of the time. I have to be careful not to do 0% for too long or I can end up with a spike.

I'm glad your dexcom is working out so well for you!

Has anyone seen this Sugar Surfing stuff:

This is partly what got me wondering about basal testing and all that... I'm beginning to think awesome control is a combination of testing rates and ratios until they are accurate maybe 50% of the time, and then using something like Sugar Surfing to take care of the other 50%. Combined with knowing how to deal with exercise, pre-bolusing, etc.