CHICAGO -- The standard practice of counting carbohydrates to better manage postprandial glycemic control in type 1 diabetes may not have substantial evidence behind it, researchers reported here.
This study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
The standard practice of counting carbohydrates to better manage postprandial glycemic control in type 1 diabetes may not have substantial evidence behind it.
Note that the review found no changes in insulin dosing, weight, or fasting plasma glucose.
In a review and meta-analysis of six randomized, controlled trials, carbohydrate counting slightly improved glycemic control with a mean drop in glycated hemoglobin (HbA1c) of -0.3%, but it wasn't significant (P=0.185), Kirstine Bell, a PhD candidate at the University of Sydney, reported at the American Diabetes Association meeting.
"There's limited evidence to recommend carbohydrate counting over other dietary interventions for improving glucose control in type 1 diabetes," Bell said. "And it's concerning that there are only six studies that could be identified when this is such an integral element of diabetes management in type 1 diabetes. It affects the management of millions of people around the world."
Carbohydrate counting is the best known method for matching insulin dosing to meals, and is the recommended dietary strategy for achieving glycemic control in type 1 diabetes, though that recommendation has been largely based on expert consensus, Bell said.
To assess the state of the literature, she and colleagues conducted a review and meta-analysis of carbohydrate counting trials in adults and children with type 1 diabetes. They ultimately included six studies with a total of 563 adults and 104 children conducted between January 1980 and April 2012.
Overall, there were five adult studies and one pediatric trail that included children, ages 8 to 13. Five trials had a parallel group design while one involved a cross-over.
All trials lasted at least 3 months and compared carbohydrate counting with usual care, which consisted of either general nutrition advice or low dietary glycemic index (GI) advice.
For their analysis, Bell and colleagues set the primary outcome of change in HbA1c, and secondary outcomes included hypoglycemia, insulin dose, weight change, fasting plasma glucose, and quality of life.
Studies were generally of good to high quality, with an overall quality score of 7.7 out of 13, the researchers reported.
Bell and colleagues found a decrease in mean HbA1c with carbohydrate counting compared with usual care (-0.3%), but it wasn't significant (P=0.185).
They were unable to conduct an analysis of secondary outcomes because of the low number of studies and inconsistencies in their reporting metrics.
They did, however, find a trend toward reduced risk of hypoglycemia and improved quality of life with carbohydrate counting.
On the other hand, there were no changes in insulin dosing, weight, or fasting plasma glucose.