Contemporary rates of severe hypoglycaemia in youth with Type 1 diabetes: variability by insulin regimen

Diabet. Med. 29, 926–932 (2012) Aims To determine incidence rates of severe hypoglycaemia and compare incidence rates by insulin regimen in a diverse sample of youth with Type 1 diabetes from two sites. Methods In this observational study, 255 youth (51% female) aged 9–15 years receiving varied insulin regimens provided data prospectively for a median of 1.2 years. Reported episodes of severe hypoglycaemia, defined as episodes requiring help from another person for oral treatment or episodes resulting in seizure/coma, and current insulin regimens were collected systematically. Incidence rates were calculated and compared according to insulin regimen in bivariate and multivariate analyses. Results At first encounter, participants had a median age of 12.2 years (range 9.0–15.0), median diabetes duration of 4.4 years (range 1.0–13.0) and mean HbA1c of 67 ± 12 mmol/mol (8.3 ± 1.1%). The incidence rate was 37.6/100 patient‐years for all severe hypoglycaemia and 9.6/100 patient‐years for seizure/coma. The incidence rate for severe hypoglycaemia was 31.8/100 patient‐years on continuous subcutaneous insulin infusion (pump therapy), 34.4/100 patient‐years on basal–bolus injections and 46.1/100 patient‐years on NPH (NPH vs. pump therapy: P = 0.04). The incidence rate for seizure/coma was 4.5/100 patient‐years on pump therapy, 11.1/100 patient‐years on basal–bolus injections and 14.4/100 patients‐years on NPH (NPH vs. pump therapy: P = 0.004). In the multivariate analysis, the rate of seizure/coma was significantly higher for those on NPH vs. pump therapy (rate ratio 2.9, P = 0.03). Conclusions Rates of severe hypoglycaemia in youth with Type 1 diabetes remain high. Pump therapy was associated with lower rates of all severe hypoglycaemia and seizure/coma in comparison with NPH.