Prevalence of impaired awareness of hypoglycemia and identification of predictive symptoms in children and adolescents with type 1 diabetes.

BACKGROUND: In children with type 1 diabetes mellitus (T1DM) the prevalence of impaired awareness of hypoglycemia (IAH) is uncertain. This study aimed to ascertain this with greater precision. Secondary aims were to assess symptoms of hypoglycemia and which of these best predict awareness of hypoglycemia in children. METHODS: Questionnaires were completed by 98 children with T1DM (mean age 10.6 yr) and their parent(s); hospital admission data for the previous year were collected. Awareness of hypoglycemia was assessed using two questionnaire-based methods that have been validated in adults. For 4 wk, participants performed routine blood glucose measurements and completed questionnaires after each episode of hypoglycemia. Principal components analysis determined how symptoms correlate; multinomial logistic regression models identified which symptom aggregate best predicted awareness status. RESULTS: The 'Gold' questionnaire classified a greater proportion of the participants as having IAH than the 'Clarke' questionnaire (68.4 vs. 22.4%). Using the 'Clarke' method, but not the 'Gold' method, children with IAH were younger and more likely to require external assistance or hospital admission. Most aged ≥9 yr (98.6%) were able to self-assess awareness status accurately. Puberty and increasing age, augmented symptom scores; duration of diabetes and glycemic control had no effect. In contrast to adults, behavioral symptoms were the best predictors of awareness status. CONCLUSIONS: IAH affects a substantial minority of children and impending hypoglycemia may be heralded by behavioral symptoms. The 'Clarke' method was more effective at identifying those at increased risk and could be used as a screening tool.

Hydroxybutyrate near-patient testing to evaluate a new end-point for intravenous insulin therapy in the treatment of diabetic ketoacidosis in children.

BACKGROUND: The aim of this study was to assess the clinical application of a near-patient testing (NPT) device for capillary blood hydroxybutyrate (HOB) measurement in evaluating a new end-point for intravenous insulin therapy in the treatment of diabetic ketoacidosis (DKA) in children. METHODS: Children fulfilling the criteria for DKA were treated according to an integrated care pathway (ICP) with fluid replacement and insulin infusion. We measured capillary HOB hourly by NPT (Abbott Optium meter, analytical range 0-6.0 mmol/L), venous blood gases 4 hourly, and venous HOB 4 hourly by laboratory enzymatic method and tested all urine passed for ketones. Two possible ICP end-points were compared: A, pH > 7.3 followed by two successive NPT HOB measurements <1 mmol/L, and B, pH > 7.3 and urine ketone free (our current end-point). RESULTS: In 35 patient episodes, the ICP was completed (28 to negative ketonuria) without significant variation. Before treatment, median (range) laboratory HOB was 9.5 mmol/L (4.6-15.70 mmol/L), pH 7.18 (6.98-7.38), and standard bicarbonate 11.5 mmol/L (4.3-18.6 mmol/L). ICP end-point A was reached after 17 h (4-39 h), whereas end-point B was not reached until 28 h (14-64 h) after starting treatment. The median lag was 11 h (1-36 h). For 59 paired venous samples (excluding samples with laboratory HOB >6 mmol/L), the relation between NPT (y) and laboratory (x) HOB was y = 0.92x - 0.05, r(2)= 0.94, mean bias -0.25 mmol/L. CONCLUSIONS: (i) Serial measurement of NPT HOB allows evaluation of a new, simple, earlier end-point for intravenous insulin therapy. (ii) Agreement between NPT and laboratory HOB was clinically acceptable for HOB levels within the meter's analytical range.