DNA methylation risk score for type 2 diabetes is associated with gestational diabetes.

BACKGROUND: Gestational diabetes mellitus (GDM) and type 2 diabetes mellitus (T2DM) share many pathophysiological factors including genetics, but whether epigenetic marks are shared is unknown. We aimed to test whether a DNA methylation risk score (MRS) for T2DM was associated with GDM across ancestry and GDM criteria. METHODS: In two independent pregnancy cohorts, EPIPREG (n = 480) and EPIDG (n = 32), DNA methylation in peripheral blood leukocytes was measured at a gestational age of 28 ± 2. We constructed an MRS in EPIPREG and EPIDG based on CpG hits from a published epigenome-wide association study (EWAS) of T2DM. RESULTS: With mixed models logistic regression of EPIPREG and EPIDG, MRS for T2DM was associated with GDM: odd ratio (OR)[95% CI]: 1.3 [1.1-1.8], P = 0.002 for the unadjusted model, and 1.4 [1.1-1.7], P = 0.00014 for a model adjusted by age, pre-pregnant BMI, family history of diabetes and smoking status. Also, we found 6 CpGs through a meta-analysis (cg14020176, cg22650271, cg14870271, cg27243685, cg06378491, cg25130381) associated with GDM, and some of their methylation quantitative loci (mQTLs) were related to T2DM and GDM. CONCLUSION: For the first time, we show that DNA methylation marks for T2DM are also associated with GDM, suggesting shared epigenetic mechanisms between GDM and T2DM.

Addition of intermittently scanned continuous glucose monitoring to standard care in a cohort of pregnant women with type 1 diabetes: effect on glycaemic control and pregnancy outcomes.

AIMS/HYPOTHESIS: The aim of this study was to assess whether the addition of intermittently scanned continuous glucose monitoring (isCGM) to standard care (self-monitoring of blood glucose [SMBG] alone) improves glycaemic control and pregnancy outcomes in women with type 1 diabetes and multiple daily injections. METHODS: This was a multicentre observational cohort study of 300 pregnant women with type 1 diabetes in Spain, including 168 women using SMBG (standard care) and 132 women using isCGM in addition to standard care. In addition to HbA1c, the time in range (TIR), time below range (TBR) and time above range (TAR) with regard to the pregnancy glucose target range (3.5-7.8 mmol/l) were also evaluated in women using isCGM. Logistic regression models were performed for adverse pregnancy outcomes adjusted for baseline maternal characteristics and centre. RESULTS: The isCGM group had a lower median HbA1c in the second trimester than the SMBG group (41.0 [IQR 35.5-46.4] vs 43.2 [IQR 37.7-47.5] mmol/mol, 5.9% [IQR 5.4-6.4%] vs 6.1% [IQR 5.6-6.5%]; p=0.034), with no differences between the groups in the other trimesters (SMBG vs isCGM: first trimester 47.5 [IQR 42.1-54.1] vs 45.9 [IQR 39.9-51.9] mmol/mol, 6.5% [IQR 6.0-7.1%] vs 6.4% [IQR 5.8-6.9%]; third trimester 43.2 [IQR 39.9-47.5] vs 43.2 [IQR 39.9-47.5] mmol/mol, 6.1% [IQR 5.8-6.5%] vs 6.1% [IQR 5.7-6.5%]). The whole cohort showed a slight increase in HbA1c from the second to the third trimester, with a significantly higher rise in the isCGM group than in the SMBG group (median difference 2.2 vs 1.1 mmol/mol [0.2% vs 0.1%]; p=0.033). Regarding neonatal outcomes, newborns of women using isCGM were more likely to have neonatal hypoglycaemia than newborns of non-sensor users (27.4% vs 19.1%; ORadjusted 2.20 [95% CI 1.14, 4.30]), whereas there were no differences between the groups in large-for-gestational-age (LGA) infants (40.6% vs 45.1%; ORadjusted 0.73 [95% CI 0.42, 1.25]), Caesarean section (57.6% vs 48.8%; ORadjusted 1.33 [95% CI 0.78, 2.27]) or prematurity (27.3% vs 24.8%; ORadjusted 1.05 [95% CI 0.55, 1.99]) in the adjusted models. A sensitivity analysis in pregnancies without LGA infants or prematurity also showed that the use of isCGM was associated with a higher risk of neonatal hypoglycaemia (non-LGA: ORadjusted 2.63 [95% CI 1.01, 6.91]; non-prematurity: ORadjusted 2.52 [95% CI 1.12, 5.67]). For isCGM users, the risk of delivering an LGA infant was associated with TIR, TAR and TBR in the second trimester in the logistic regression analysis. CONCLUSIONS/INTERPRETATION: isCGM use provided an initial improvement in glycaemic control that was not sustained. Furthermore, offspring of isCGM users were more likely to have neonatal hypoglycaemia, with similar rates of macrosomia and prematurity to those of women receiving standard care.

Expert Study: Utility of an Automated Bolus Advisor System in Patients with Type 1 Diabetes Treated with Multiple Daily Injections of Insulin-A Crossover Study.

OBJECTIVE: This study was designed to assess the impact of the use of an automated bolus advisor (ABA) on glycemic control, quality of life, and satisfaction in adult patients with type 1 diabetes mellitus treated with multiple daily injections of insulin. MATERIALS AND METHODS: A crossover, prospective, randomized, controlled, multicenter study of 36 weeks duration was conducted. Patients were randomized to start in either control phase (CP) using a traditional blood glucose meter to calculate insulin doses (Accu-Chek(®) Aviva Nano; Roche Diagnostics, Indianapolis, IN) or intervention phase (IP) using an ABA meter (Accu-Chek Aviva Expert; Roche Diagnostics) and switched to the other phase after a washout period. Each phase was 12 weeks in duration. RESULTS: Significant glycated hemoglobin (HbA1c) reduction was observed in both phases (CP, initial HbA1c of 8.05 ± 0.7%, final HbA1c of 7.59 ± 0.7% [P < 0.001]; IP, initial HbA1c of 8.13 ± 1%, final HbA1c of 7.61 ± 0.8% [P < 0.001]). Although the trend was to a higher HbA1c reduction in IP, no statistically significant differences were observed between phases (CP, HbA1c -0.39%; IP, HbA1c -0.52% [P = 0.8]). During IP, the number of daily glucose measurements was greater (4.28 ± 1.2 vs. 4.01 ± 1.1 [P < 0.006]), the rate of postprandial hypoglycemia was lower, and an improvement in quality of life and higher satisfaction were observed. CONCLUSIONS: In this first crossover study comparing the use of an ABA with the standard usual care, the use of an ABA was effective and well accepted. Furthermore, reduction in hypoglycemic events, improvement in adherence and quality of life, and higher treatment satisfaction were observed.

Hemoglobin A1c versus oral glucose tolerance test in postpartum diabetes screening.

OBJECTIVE: To determine the usefulness of measuring hemoglobin A(1c) (A1C), alone or combined with the fasting glucose test, compared with the oral glucose tolerance test (OGTT) for the reassessment of the carbohydrate metabolism status in postpartum women with a history of gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS: We evaluated the status of carbohydrate metabolism by performing the OGTT and fasting glucose and A1C tests in 231 postpartum women with prior GDM 1 year after delivery. RESULTS: The prevalence of abnormal carbohydrate metabolism was 45.89% by the OGTT criterion, 19.05% by the A1C test criterion, 38.10% by the fasting glucose test criterion, and 46.75% by the A1C-fasting glucose test criteria. Using the OGTT as the gold standard, abnormal carbohydrate metabolism according to the A1C test criterion had 22.64% sensitivity and 54.55% positive predictive value; abnormal carbohydrate metabolism by the fasting glucose criterion had 83.02% sensitivity and 100% positive predictive value. The A1C-fasting glucose test criteria classified 18 women with normal carbohydrate metabolism as having abnormal carbohydrate metabolism. Abnormal carbohydrate metabolism by the A1C-fasting glucose test criteria had 83.02% sensitivity and 81.48% positive predictive value. CONCLUSIONS: Our results seem to indicate that the A1C test criterion alone or in combination with fasting glucose test criterion does not provide a sensitive and specific diagnosis of abnormal carbohydrate metabolism in women who have had GDM.