I wanted to know if there was any observed rebound phenomenon above 2.20 or so. I have noticed that my rebound in the morning are never above 1.70 and I base my case on the fact that I will have no sugar in my urines but trace to one cross (the french unit for measuring acetone) of acetone. Furthermore, not long ago I went on a hike and I forgot my sugar, but not my measuring kit, I caught a little hypo (0.58) and since I did not have a big dose before lunch I figured I would not pass out (my wife was with me and could have gone for help) any way I felt bad and rebounded to 0.90 were I was steady for the rest of the day. The hospital where I am treated has conducted research in the rebound phenomenon and they concluded it did not exist beyond a certain level, thus my question. I however have noticed that following a hypo I will develop a certain resistance to insulin and usually I will need to make a bigger insulin bolus (I use a pump) in the following meal if close in time to the hypo.

Secondly I wish to make a comment about heart rate monitor that might be useful to people who do endurance sports, I have found that using a heart beat monitor has allowed me to catch hypos when I run (for some reasons I don’t feel them while running, during the day, I feel bad at 0.6, when I run I feel fine at 0.4). I run at a set heart rate say 145 beat per minutes. After a while you can guess what kind of speed to expect at that heart rate, if however I notice the heart rate is going up for no apparent reasons (stiff hill, bad driver nearly missing me etc) I measure my sugar and nine times out of ten I am in hypo.

I am not aware of any study that have defined so precisely the amount of the rebound phenomenon (also called Somogyi’s effect) even it’s quite true that most of the rebound hyperglycemia is generally due to the overeating of the patient to counteract low blood sugar. Moreover, in your case the pump through its continuous insulin infusion over 24 hours contributes to smoothing the wide excursions of blood sugar after the low values. Transitory insulin resistance is secondary to the endocrine and metabolic consequences of counter regulatory response to low blood sugar and it is rather common. Regarding heart rate and hypoglycemia unawareness: yes, it’s true that your heart can spot your low blood sugar a mile away while you have noticed yet no symptoms that your sugar has started to dip. As you probably know most of the diabetic patients feel low blood sugar around 80mg/dl whilst others may not feel until they reach 30mg/dl. I’s called hypoglycemia unawareness and it’s due to having too tight blood sugar control, often on a pump, or any other way aimed to achieve the best metabolic control. It seems that the closer to normal you keep your blood sugars, the lower your sugars get before you have any symptoms. In this case it may be wise to ease off on the control a bit to allow the body to readjust to give you clues at higher blood sugar levels. Try not to overtreat your diabetes because in hypoglycemia unawareness low blood sugars when long enough may cause sudden neurological manifestations (such as coma) that can be very dangerous if for example you’re driving or you’re sleeping. Ask your diabetes team for further advice.

MS