Studies of children with type 1 diabetes focusing on national mean HbA1c levels obscure variations within countries and provide inadequate measures of glycemic control, according to a study published in Diabetes Care.
This may result in a lack of informed policy-making regarding the health care system’s management of childhood diabetes, according to the researchers.
“Within-country studies have reported substantial differences in glycemic control across pediatric diabetes centers,” Dimitrios Charalampopoulos, PhD, MPhil, MSc, research associate at UCL Great Ormond Street Institute of Child Health at University College London, and colleagues wrote. “Although some of these variations could be related to differences in patient case mix or preferences, some others may reflect differences in quality of, or access to, diabetes care. These unwarranted variations raise concerns about the equity of health care systems.”
In a cross-sectional study conducted from 2013 to 2014, researchers analyzed data from six large population registries of 64,666 children with type 1 diabetes across 528 pediatric diabetes centers in Germany, Austria, England, Wales, the United States, Sweden, Denmark and Norway. Researchers used fixed and random-effects models adjusted for age, sex, diabetes duration and minority status. Minority status was determined according to the patient’s or patient’s parents’ country of birth or the patient’s ethnicity.
Researchers estimated mean HbA1c level for each center and assessed the proportion of total variation in HbA1c between centers in each country. They then pooled all glycemic data to examine whether differences in mean HbA1c levels between countries continued after removing center effects and differences in the children’s risk profiles across countries.
The lowest mean HbA1c (7.6%) together with the lowest variation among centers was found in Sweden; Norway and Denmark also had the lowest between-center variations. The largest center variations (interclass correlation of approximately 15%) were found in Germany and Austria, which had the next lowest HbA1c levels (7.7% and 7.8%, respectively). Across all countries, centers with more variation in glycemic results also had higher HbA1c levels.
These findings suggest that whole-country mean HbA1c levels do not provide a fully accurate summary of the glycemic performance of a country, according to the researchers.
“The distribution of glycemic achievement across centers within countries should be considered, alongside national mean values, in developing informed policies that drive quality improvement,” they wrote. – by Melissa J. Webb
Disclosures: Charalampopoulos reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.