Hemoglobin A1c (HbA1c) levels before initiating the use of an insulin pump predicted the extent to which insulin pump therapy improved glycemic control in children with type 1 diabetes (T1D), according to study results published in Pediatric Diabetes.
To examine the effects of insulin pump therapy on HbA1c in children with T1D and the specific role pre-pump HbA1c plays in the results, researchers retrospectively followed 125 individuals who started insulin pump therapy at a tertiary Canadian pediatric hospital (median age at initiation of therapy, 11.0 years).
The researchers utilized a Generalized Estimating Equation method to estimate pre-pump mean HbA1c and examine mean changes before and after pump initiation in each participant. Patients were classified as having good, moderate, or poor metabolic control (mean pre-pump HbA1c level <7.5%, 7.5-9.0%, and >9.0%, respectively).
Of the total population, 37 patients had good pre-pump metabolic control, 72 moderate metabolic control, and 16 poor metabolic control. The poor control group had a lower median age at diagnosis of T1D and an increased length of time to pump initiation than the moderate and good control groups.
Adjusting for possible confounders, the researchers discovered that HbA1c levels decreased by an average of 0.48% (P <.0001) after insulin pump therapy. The adjusted mean HbA1c levels were reduced by 0.14% in the group with good metabolic control (P =.188), 0.54% in the group with moderate metabolic control (P <.0001), and 1.08% in the group with poor metabolic control (P =.0006).
Several limitations were noted for this study, including its retrospective design, relatively small sample size, and short, 18-month follow-up period.
“Our study demonstrates for the first time in a large cohort of young children the varying degree of improvement in HbA1c after [insulin pump therapy] initiation based on the children’s pre-pump HbA1c after controlling for other potentially confounding variables,” the researchers said. “These results highlight that eligibility and consideration for [insulin pump therapy] should be expanded to routinely include children with high HbA1c.”
Botros S, Islam N, Hursh B. Insulin pump therapy, pre-pump HbA1c and metabolic improvement in children with type 1 diabetes at a tertiary Canadian children’s hospital [published online February 18, 2019]. Pediatr Diabetes. doi:10.1111/pedi.12834