Scientific Publications Database

Article Title: Continuous Glucose Monitoring in Pregnant Women With Type 1 Diabetes (CONCEPTT): A Multicenter International Randomised Controlled Trial
Authors: Feig, Denice S.; Donovan, Lois E.; Corcoy, Rosa; Murphy, Kellie E.; Amiel, Stephanie A.; Hunt, Katharine F.; Asztalos, Elizabeth; Barrett, Jon F. R.; Sanchez, J. Johanna; de Leiva, Alberto; Hod, Moshe; Jovanovic, Lois; Keely, Erin; McManus, Ruth; Hutton, Eileen K.; Meek, Claire L.; Stewart, Zoe A.; Wysocki, Tim; O'Brien, Robert; Ruedy, Katrina; Kollman, Craig; Tomlinson, George; Murphy, Helen R.
Journal: OBSTETRICAL & GYNECOLOGICAL SURVEY Volume 73 Issue 4
Date of Publication:2018
Abstract:
It is established that optimal maternal glycemic control throughout pregnancy is associated with a decrease in adverse fetal outcomes. A proper glycemic index can be difficult to control in women with type 1 diabetes during pregnancy because of the complexity of insulin dose adjustment, gestational changes in insulin sensitivity, and day-to-day changes to insulin absorption in late pregnancy. Nationwide UK data show the rates of severe hypoglycemia, particularly in early pregnancy, are 5 times higher among pregnant women than nonpregnant and that only 40% of women with type 1 diabetes achieve target glycated hemoglobin (HbA(1c)) after 24 weeks of gestation. Continuous glucose monitoring (CGM) provides real-time quantitative information on the direction and rate of change of glucose levels.This multinational, randomized controlled study included 2 parallel trials: a pregnancy trial and a planning-pregnancy trial. The goals of the study were to evaluate CGM use before and fromearly pregnancy on maternal glucose control, obstetric outcomes, and neonatal health outcomes. Subjects were recruited if they were aged 18 to 40 years, had type 1 diabetes, were currently receiving intensive insulin therapy, and were pregnant or planning pregnancy. Participants were randomized into a cohort receiving capillary glucose monitoring and CGM or capillary glucose monitoring alone. The primary outcome measured was rate of change of HbA(1c) from randomization (first measurement) to 34 weeks in the pregnancy trial and to 24 weeks or conception in the planning-pregnancy trial. Secondary outcomes for both trials included percentage of time spent outside glucose target range (3.5-7.8 mmol/L), area under the curve for glucose levels, hypoglycemic episodes, glucose variability derived from CGM measures, and prespecified health outcomes.A total of 325 participants were enrolled, with 215 pregnant and 110 planning pregnancy. There was a small but significant difference in the change of HbA(1c) between baseline and 34 weeks' gestation between the 2 groups in the pregnancy trial favoring CGM (mean difference, -0.19%; 95% confidence interval [CI], -0.34 to -0.03; P = 0.0207). In the planningpregnancy trial, the difference was similar in size but had a wider CI and was not significant. In the pregnancy trial, the women in the CGM group showed evidence of less glycemic variability: increased time in the glucose target range, reduced glucose SD, and lower mean amplitude of glucose excursion. Pregnant CGM users spent 68% of their time in the glucose target range and 27% of their time hyperglycemic compared with 61% and 32%, respectively, for their counterparts in the control group. Results showed a decreased incidence in large for gestational age (odds ratio [OR], 0.51; 95% CI, 0.28-0.29; P = 0.0210), fewer neonatal intensive care unit admissions formore than 24 hours (OR, 0.48; 95% CI, 0.26-0.86; P = 0.157), 1-day shorter length of hospital stay (P = 0.0091), and fewer incidents of neonatal hypoglycemia requiring treatment (OR, 0.45; 95% CI, 0.22-0.89; P = 0.250) among the CGM group compared with the control group.The small improvement in HbA(1c) is likely related to a reduced neonatal exposure to maternal hyperglycemia. No benefit of CGM in women planning pregnancy was demonstrated, although this component of the study was underpowered. The results of this study show CGM should be considered in the management of type 1 diabetes for all pregnant patients using intensive insulin therapy.