The New GDM Screening Guidelines Jennifer Klinke MD, FRCPC Endocrinologist and Co director RCH Diabetes in Pregnancy Program
Disclosures Current participant (RCH site) for MiTy study Metformin in women with Type 2 diabetes in pregnancy study
Objectives Why are we changing our practice? What are the current guidelines for GDM screening? Should we be screening our obese patients in early pregnancy? If so, which test should I order?
2 recent RCTs for treatment of GDM ACHOIS Crowtheret al. NEJM 2005;352:2477 86. 1000 women with GDM (by 75g OGTT, at 24 34 weeks with FPG < 7.8 mmol/l and 2h glucose 7.8 11.0 mmol/l Intervention (n= 510) diet, SMBG, + insulin prn Control (n=490) routine prenatal care Landon et al. NEJM 2009;361:1339 48. 958 women with mild GDM (by 100 g OGTT, at 24 31 weeks, with FPG < 5.3 mmol/l AND at least 2 elevated numbers on 1h, 2h or 3h) Intervention (n= 485) diet, SMBG, + insulin prn Control (n=473) routine prenatal care
ACHOIS Australian Carbohydrate Intolerance Study in Pregnant Women 1 Outcomes: Serious perinatal complications (death, shoulder dystocia, bone fracture, nerve palsy) Jaundice requiring phototherapy NICU admission Induction of labor Cesarean delivery Maternal anxiety, depression, and health status NEJM 2005;352:2477 86.
ACHOIS Outcome Intervention N= 506 (infants) N= 490 (women) Control N= 524 (infants) N= 510 (women) Adjusted RR (95% CI) Adjusted p value Serious perinatal complications NICU admission Jaundice req phototherapy 7 (1%) 23 (4%) 0.33 (0.14 0.75) 0.01 357 (71%) 321 (61%) 1.13 (1.03 1.23) 0.01 44 (9%) 48 (9%) 0.93 (0.63 1.37) 0.72 IOL 189 (39%) 150 (29%) 1.36 (1.15 1.62) <0.001 Cesarean 152 (31%) 164 (32%) 0.97 (0.81 1.16) 0.73 NEJM 2005;352:2477 86.
At 3 months post partum Lower rates of depression and higher health status scores in the intervention group
ACHOIS conclusions Treatment of GDM reduces serious perinatal morbidity May also improve the woman s health related quality of life
Landon et al. study Primary outcomes Composite of perinatal mortality (stillbirth or NND), neonatal hypoglycemia, hyperbilirubinemia, neonatal hyperinsulinemia, and birth trauma Secondary outcomes Birth weight >4kg Admission to NICU Respiratory distress syndrome Maternal weight gain Gestational HTN and preeclampsia IOL and Cesarean delivery Shoulder dystocia
Landon study 1 Outcome Outcome Composite end pointno./total no. (%) Intervention (n=485) Control (n=473) Relative Risk (97% CI) 149/460 (32.4) 163/440 (37.0) 0.87 (0.72 1.07) P value 0.14 Hypoglycemia 62/381 (16.3) 55/357 (15.4) 1.06 (0.73 1.53) 0.75 Hyperbilirubi nemia Elevated cord C peptide Stillbirth or NND 43/450 (9.6) 54/418 (12.9) 0.74 (0.49 1.12) 0.12 75/423 (17.7) 92/403 (22.8) 0.78 (0.57 1.05) 0 0 Birth trauma 3/476 (0.6) 6/455 (1.3) 0.48 (0.10 2.20) 0.07 0.33 NEJM 2009;361:1339 48.
2 Neonatal Outcomes Outcome Birth weight grams Birth weight >4kg Intervention (n=485) Control (n=473) Relative Risk (97% CI) P value 3302 ±502.4 3408 ±589.4 <0.001 28/477 (5.9%) 65/454 (14.3%) 0.41 (0.26 0.66) <0.001 LGA 34/477 (7.1%) 66/454 (14.5%) 0.49 (0.32 <0.001 0.76) Fat mass 427.0 ± 197.9 464.3 ± 222.3 0.003 grams NICU Admission 43/477 (9.0%) 53/455 (11.6%) 0.77 (0.51 1.18) 0.19 Respiratory distress syndrome 9/477 (1.9%) 13/455 (2.9%) 0.66 (0.26 1.67) NEJM 2009;361:1339 48. 0.33
Maternal Outcomes Outcome Intervention (n=476) Control (n=455) Relative Risk (97 % CI) P value IOL no. (%) 130 (27.3%) 122 (26.8%) 1.02 (0.81 1.29) 0.86 Cesarean deliveryno. 128 (26.9%) 154 (33.8%) 0.79 (0.64 0.99) 0.02 (%) Shoulder dystocia 7 (1.5%) 18 (4.0%) 0.37 (0.14 0.97) 0.02 no.(%) Preeclampsia 12 (2.5%) 25 (5.5%) 0.46 (0.22 0.97) 0.02 no. (%) Preeclampsia or 41 (8.6%) 62 (13.6%) 0.63 (0.42 0.96) 0.01 gestational HTN BMI at delivery 31.3 ± 5.2 32.3 ± 5.2 <0.001 Weight gain kg 2.8 ±4.5 5.0 ± 3.3 <0.001 NEJM 2009;361:1339 48.
Landon study conclusions Treatment of mild GDM did not significantly reduce frequency of composite outcome (stillbirth, NND, and several neonatal complications) Treatment did reduce risks of fetal overgrowth, shoulder dystocia, cesarean delivery, and hypertensive disorders
HAPO study Hyperglycemia and Adverse Pregnancy Outcomes Design: 25,505 women (15 centres, 9 countries) underwent 75g OGTT at 24 32 weeks 23,316 were available for analysis Singleton pregnancies, spontaneous conception No pre existing diabetes 1 Outcomes: BW >90 th percentile for GA Primary cesarean delivery Clinical neonatal hypoglycemia Cord blood C peptide >90 th percentile NEJM 2008;358:1991 2002.
HAPO study 2 Outcomes: Preterm delivery (<37 weeks) Shoulder dystocia or birth injury NICU admission Hyperbilirubinemia Preeclampsia Analysis: calculated adjusted OR for adverse outcomes associated with increasing fasting, 1h, and 2h plasma glucose
HAPO: Conclusions Increasing levels of fasting, 1h and 2h glucose on 75g OGTT continuously associated with Birth weight >90th %ile Cord blood serum C peptide >90th %ile Weaker associations with Primary cesarean delivery Clinical neonatal hypoglycemia Positive associations with Premature delivery Shoulder dystocia or birth injury Intensive neonatal care Hyperbilirubinemia Preeclampsia
HAPO Conclusions No obvious thresholds at which risks increased Need to reconsider the current criteria for diagnosing hyperglycemia during pregnancy
IADPSG Consensus panel International Association of Diabetes and Pregnancy Study Groups Mean values for glucose in HAPO study were considered the reference concentrations FPG 4.5 mmol/l, 1h glucose 7.4 mmol/l, 2h glucose 6.2 mmol/l OR 1.75 relative to the mean was considered the threshold for diagnosis of GDM
2010 IADPSG Recommended Diagnostic Criteria for GDM 75 g OGTT (one of more values) FPG 5.1 1h glucose 10.0 2h glucose 8.5 Diabetes Care 2010;33:676 82.
2010 Recommended Diagnostic Criteria for Overt Diabetes in pregnancy One of: FPG 7.0 mmol/l A1c 6.5% Random glucose 11.1 mmol/l (plus confirmation with either FPG or A1c) If FPG 5.1 and < 7.0, then diagnose as GDM If FPG < 5.1, then do 75g OGTT between 24 and 28 weeks Diabetes Care 2010;33:676 82.
Early screening? CDA recommends: women with multiple risk factors should be screened during the first trimester Can J of Diabetes 2008;32(Suppl 1) s168. IADPSG: first prenatal visit measure FPG, A1c or random glucose on all or only high risk women Diabetes Care 2010;33:676 82. ADA: screen for undiagnosed type 2 diabetes at the first prenatal visit in those with risk factors, using standard diagnostic criteria Diabetes Care 2011;34(Suppl 1):S4 S10.
Risk factors GDM Previous GDM Previous macrosomic infant High risk ethnic group Age 35 BMI 30 PCOS Acanthosis nigricans Corticosteroid use Type 2 diabetes History of IFG or IGT or GDM Previous macrosomic infant High risk ethnic group Age 40 Overweight or abdominal obesity PCOS Acanthosis nigricans First degree relative with T2DM Schizophrenia Can J of Diabetes 2008