Comparative Efficacy of Insulin Pumps vs Multiple Daily Injections for Pregnant Patients with Type 1 Diabetes

Trial examines differences in glycemic control and quality of life when using different insulin delivery methods.

The use of insulin pumps is becoming more prevalent in patients with type 1 diabetes due to recent evidence suggesting that it provides better glycemic control and less variability than traditional multiple daily injection regimens. The evidence driving these clinical decisions has been derived from studies that focus primarily on women who have type 1 diabetes and are not pregnant. Consequently, the conclusions drawn from these studies can’t necessarily be extended into pregnancy. Some studies have been conducted regarding this topic, however, the results were varied, and the studies were plagued with obvious limitations (small sample size, use of outdated equipment, lacking statistical power, etc.). The aim of this study is to assess the comparative benefit of using insulin pumps against the more traditional multiple daily injection regimens in pregnant patients with type 1 diabetes.

In order to achieve the aim of this study, the researchers reanalyzed the data collected during the Continuous Glucose Monitoring in Type 1 Diabetes Pregnancy Trial (CONCEPTT). The CONCEPTT trials aim was to assess the utility of continuous glucose monitoring vs self-monitoring of blood glucose; however, they stratified the groups based on method of insulin delivery (insulin pump and multiple daily injections). For the CONCEPTT trial, patients were considered for inclusion if they had been diagnosed with type 1 diabetes more than 12 months ago, were between the ages of 18 and 40, were or were planning to become pregnant, and were on an intensive insulin regimen consisting of either multiple daily injections or use of an insulin pump. For this reanalysis, the primary outcome of interest was glycemic control (assessed via change in A1C). Quality of life and pregnancy outcome were assessed secondarily. A1C and quality of life were assessed at baseline and then again at 34 weeks gestation via laboratory analysis and research-validated questionnaire (12-Item Short Form Survey or SF-12) respectively. Pregnancy outcomes were assessed at each prenatal physician visit and at birth. Statistical significance was determined via a two-tailed Analysis of Co-Variants (ANCOVA) with a threshold for significance set at 5%.

Data from all of the 248 participants enrolled in the CONCEPTT trial was used for this study. Since the groups were originally stratified based on type on insulin delivery method, there was a nearly equal number of individuals in each group. Baseline characteristics between groups were fairly equivalent; however, the women in the insulin pump groups were on average more likely to be in a stable relationship and to regularly take preconception vitamins (for those planning to become pregnant) and less likely to smoke.

At the close of the study, it was found that the patients who used multiple daily injections demonstrated a larger reduction in A1C when compared to those using an insulin pump (-0.55 compared to -0.32 respectively, p = 0.01). Likewise, those on an insulin pump reported a larger decline in perception of health and well-being than those on multiple daily injection regimens (p = 0.02). Concerning pregnancy outcomes, those in the insulin pump group exhibited higher rates of hypertensive disorders, neonatal hypoglycemia requiring treatment, and NICU admissions lasting for greater than 24 hours compared to those taking multiple daily insulin injections (p = 0.011, 0.05, and 0.02 respectively).

The results of this study indicate that for women who have type 1 diabetes and are pregnant, multiple daily insulin injections are associated with better glycemic control, higher quality of life, and less complications during pregnancy, when compared to use of an insulin pump. Consequently, use of multiple daily insulin injections may be considered preferentially against insulin pump use in this patient population.

Practice Pearls:

• Unmanaged type 1 diabetes can complicate pregnancy, necessitating clinical intervention.
• Multiple daily insulin injections are associated with better glycemic control, higher reported quality of life, and less complications during pregnancy than use of an insulin pump in women who have type 1 diabetes and are pregnant.
• For patients with type 1 diabetes and pregnancy, multiple daily insulin injections may be considered preferentially against insulin pump use.

Reference:

Feig, Denice S., et al. “Pumps or Multiple Daily Injections in Pregnancy Involving Type 1 Diabetes: A Prespecified Analysis of the CONCEPTT Randomized Trial.” Diabetes Care, vol. 41, no. 12, 2018, pp. 2471–2479., doi:10.2337/dc18-1437.

Michael Zaccaro, Pharm. D. Candidate 2019, LECOM School of Pharmacy