Posted Sep 12 , 2017 03:00 AM

Accurate Carbohydrate Counting Is an Important Determinant of Postprandial Glycemia in Children and Adolescents with Type 1 Diabetes on Insulin Pump Therapy

Deeb A, et al. J. Diab. Sci and Technol. 2017;11: 753 –758

What were the findings (excerpted from the Abstract)?

Carbohydrate (CHO) counting is a key nutritional intervention utilized in the management of diabetes to optimize postprandial glycemia. The aim of the study was to examine the impact of accuracy of CHO counting on the postprandial glucose in children and adolescents with type 1 diabetes on insulin pump therapy. Children/adolescents with type 1 diabetes who were on insulin pump therapy for a minimum of 6 months were enrolled in the study. Patients were instructed to record details of meals consumed, estimated CHO count per meal, and 2-hour postprandial glucose readings over 3-5 days. Meals’ CHO contents were recounted by an experienced clinical dietician, and those within 20% of the dietician’s counting were considered accurate. A total of 30 patients (21 females) were enrolled. Age range (median) was 8-18 (SD 13) years. Data of 247 meals were analyzed. A total of 165 (67%) meals’ CHO contents were accurately counted. Of those, 90 meals (55%) had in-target postprandial glucose (P < .000). There was an inverse relationship between inaccurate CHO estimates and postprandial glucose. Of the 63 underestimated meals, 55 had above-target glucose, while 12 of the 19 overestimated meals were followed by low glucose. There was no association between accuracy and meal size. Accuracy of CHO counting is an important determining factor of postprandial glycemia. However, other factors should be considered when advising on prandial insulin calculation. Underestimation and overestimation of CHO result in postprandial hyperglycemia and hypoglycemia, respectively. Accuracy does not correlate with meal size.

Why is this important?

Carbohydrate counting is one of several determinants of blood glucose values after meals, a key component of glycemic variability (Kildegaard J, et al. J. Diab. Sci. Technol. 2009;3:986). Both the amount and type of CHO in a meal influence postprandial blood glucose levels. However, the amount rather than the glycemic index (GI) of the CHO in the food is most often the primary determinant of postprandial response. It is important to note that carbohydrate counting accuracy is reasonably high in individuals on insulin pump therapy, but there are other factors such as variability in insulin sensitivity from day-to-day, timing of insulin bolus for the meal, etc. Like many facets of diabetes care, occasional re-training in the skill of carbohydrate counting will likely help identify individuals who can improve that skill with practice. Do you ever test your patients’ skill in carbohydrate counting? Have you referred individuals for re-training to hone that skill to improve insulin therapy effectiveness? Your colleagues would like to hear your experiences with this important skill in your type 1 patients especially.

Read the Abstract: