Dramatic I:C Ratio Change over a short period of time


I'm 42 with LADA (Type 1 ?), diagnosed at 38. I presented originally at age 34 as Type 2 misdiagnose as I was 275lbs at the time. Easy GP mistake I guess.

I weigh 160lbs now and have been pumping Humalog through an Animas Ping for 2 years.

Over the last couple of days my I:C has gone from a 1:10 to a 1:13ish (still working on getting the numbers straight).

My question is this; Are there any factors that would cause such a dramatic swing in such a short time?



I see changes of that magnitude when the seasons change.

I just had full CBC and more when I went to the ER for ketones that wouldn't go away. This has me thinking that maybe I was running trace ketones for a long time? I've always required more insulin for my first meal. Hmmm...

How did you determine your I:C needed changing?

Your post leads one to believe that your insulin requirements are dropping your experiencing low BG? I would never suspect that my insulin requirements would drop because of infection or illness. My requirements also go up during the winter because my activity level drops and I need a little more fuel to stay warm. My I:C and sensitivity increases from morning to evening about 30%.

If your I:C is changing then your sensitivity (correction factor is also changing). Also shortening duration will increase correction insulin if your out of target range, increasing the time will make your bolus wizard a little less aggressive.

Are you absolutely sure your basal is correct, are you having site rejection or absorption issues. I sometimes have huge swings in absorption based on my infusion location and time.

If I was not using a CGM I would base my changes on 30 day averages and would spread my meals out to at least 6 hours apart so there was no active bolus insulin when I test and bolus for meals before making a change.

Yes. I was needing less insulin to cover carbs and my basal rate was dropping my bgl overnight. However, I just woke to a 150 so I am thinking things are back to normal. I will have to test factors, rates and ratios this week again.