Correlation Between Amount of Carbohydrate in Mixed Meals and Insulin Delivery by Artificial Pancreas in Seven IDDM Subjects

The effects of mixed meals containing varying amounts of carbohydrate (CHO) on blood glucose levels and insulin delivery by an artificial pancreas were studied in seven insulin-dependent diabetes mellitus subjects. Each patient received, at random over 3 consecutive days, three mixed meals containing 60, 80, and 140 g complex CHOs. There was a high and linear correlation between total amount of insulin delivered to restore blood glucose values and amount of CHO consumed: 12.1 +/- 1.3 to 31.2 +/- 5.2 U insulin were needed for 116 +/- 16 to 198 +/- 24 min. However, neither the time lapse between the beginning of meal intake and blood glucose increase nor the peaking time for blood glucose variation were significantly different between meals. We suggest that some of the data obtained in this study might be useful in programming an open-loop insulin-infusion system.