Endocrine Abstracts

Introduction: There is concern that lowering the HbA1c target for children and young people with T1DM would increase the amount and severity of hypoglycaemia.

Aims: To examine the relationship between HbA1c and blood glucose (BG) levels, particularly hypoglycaemia, in children with T1DM treated to current target.

Methods: BG meter downloads (Diasend) were examined for the 3 months before the latest HbA1c level in children with HbA1c lower than 58 mmol/mol in the Oxford clinic. Average number of BG readings, percentage of in-target (between 4.0 and 7.0 mmol/l) and low (<4.0 mmol/l) BG readings, and mean BG levels were recorded.

Results: Between September and November 2014, 127 children (37.5% all patients) had HbA1c levels lower than 58 mmol/l (range 30–57 mmol/mol). 92 had BG meter downloads available (55M, 37F, age 2.3–18.2 year, × 11.8 year, duration 0.23–14.29 year, × 3.10 year). 23 (25%) used insulin pumps and 69 (75%) multiple daily injections (MDI). Number of BG tests per day was 0.5–11.9 (mean 5.5). HbA1c was related to mean BG level (r=0.64, P<0.0001), duration (r=0.28, P=0.007) but not to age. HbA1c was no different in those using MDI (49.5) than pumps (48.0, P=0.3). Percentage BG levels <4 mmol/l was not related to HbA1c (r=0.06). 39 had HbA1c levels </=48 mmol/mol and 53 had HbA1c >48 mmol/mol, There was no significant difference between these groups in percentage BG <4 mmol/l (11% vs 13%, P=0.16) or percentage BG <2 mmol/l (0.1% vs 0.3%, P=0.09), but the group with the lower HbA1c levels had a significantly greater percentage BG levels in target (49% vs 33%, P<0.001). 1 child had a severe episode of hypoglycaemia.

Conclusions: In children already achieving target HbA1c levels, those with HbA1c </=48 mmol/mol have no increase in hypoglycaemia, but have a greater percentage BG levels in target.