medwireNews: A comparison of glycaemic control in children younger than 6 years in US and European diabetes registries suggests that a stringent target can be achieved without ill effects.

Children in the European registry achieved lower glycated haemoglobin (HbA1c) levels than their US counterparts, at an average of 7.4% versus 8.2%.

Data for the 1948 European children came from the Prospective Diabetes Follow-up Registry (DPV) in Germany and Austria, and data for the 674 US children came from the T1D Exchange Registry. The American Diabetes Association (ADA) recommends an HbA1c target of less than 8.5% for children younger than 6 years, whereas the International Society for Pediatric and Adolescent Diabetes (ISPAD) recommends a target below 7.5%.

More European than US children achieved both the ISPAD HbA1c target (56 vs 22%) and the ADA target (90 vs 66%).

Importantly, the lower HbA1c levels in European children did not increase the rate of severe hypoglycaemic events during the previous 12 months, which was 1.9% compared with 2.8% in the US children. The difference in HbA1c levels was partly, but not entirely, accounted for by greater use of insulin pumps in the European children, at 74% compared with 50% in US children. The researchers found the two groups to be broadly similar in terms of clinical characteristics and management, and the difference in HbA1c levels persisted after accounting for variables including pump use, with adjusted levels being 0.7% higher in European than US children.

DuBose et al therefore hypothesise that the different HbA1c targets may explain the difference that remained in children’s HbA1c levels after accounting for pump use, assuming that US physicians treated according to the ADA target and European physicians to the ISPAD target. They say it “may be more than a coincidence” that the proportion of US children who met the ADA target is similar to the proportion of European children who met the ISPAD target.

The higher ADA target is partly due to concern about the neurocognitive effects of severe hypoglycaemic events. Consequently, the absence of an increased risk of these events in European children is “one of the most important findings of the study”, say researcher Stephanie DuBose (Jaeb Centre for Health Research, Tampa, Florida, USA) and team.

They add that increasing evidence suggests that diabetic ketoacidosis (DKA) and hyperglycaemia may also have adverse effects on developing brains. “Thus, it is particularly noteworthy with respect to safety concerns that better HbA1c outcomes in the DPV registry were associated with a lower frequency of DKA”, they write in Diabetologia.

The DKA rate in the European children was 3.0%, which was significantly lower than the 6.0% in US children.

By Eleanor McDermid, Senior medwireNews Reporter

Diabetologia 2014; Advance online publication

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