Gestational Diabetes:Diagnosis, Treatment

Long Term Management, and

FollowupEric Lind Johnson, M.D.Assistant Professor

Department of Family and Community MedicineUniversity of North Dakota School of Medicine

And Health SciencesAssistant Medical Director

Altru Diabetes CenterGrand Forks, ND

Objectives

• Discuss Gestational Diabetes Mellitus (GDM) and Treatment

• Recognize common problems of GDM in Pregnancy

• Discuss long term followup of Gestational Diabetes Mellitus (GDM)

Gestational Diabetes Mellitus

Gestational Diabetes

• Reduced sensitivity to insulin in 2nd and 3rd trimesters

• “Diabetogenic State” when insulin production doesn’t meet with increased insulin resistance

Hod and Yogev Diabetes Care 30:S180-S187, 2007Crowther, et al NEJM 352:2477–2486, 2005 Langer, et al Am J Obstet Gynecol 192:989–997, 2005

Gestational Diabetes

• Human placental lactogen, leptin, prolactin, and cortisol result in insulin resistance

• Lack of diagnosis and treatment-increased risk of perinatal morbidities

Hod and Yogev Diabetes Care 30:S180-S187, 2007Crowther, et al NEJM 352:2477–2486, 2005 Langer, et al Am J Obstet Gynecol 192:989–997, 2005

Gestational Diabetes

• Occurs in 2-9% of pregnancies

• ~135,000 cases in U.S. annually

• Management can include insulin (usually preferred, better efficacy) or sulfonylureas (in very select cases)

Am J Obstet Gynecol 192:1768–1776, 2005Diabetes Care 31(S1) 2008 Diabetes Care 25:1862-1868, 2002

Gestational Diabetes and Type 2 Diabetes Risk

• Gestational Diabetes should be considered a pre-diabetes condition

• Women with gestational diabetes have a 7-fold future risk of type 2 diabetes vs.women with normoglycemic pregnancy

Lancet, 2009, 373(9677): 1773-9

Gestational Diabetes-Screening

• Screen all very high risk and high risk

• Very high risk: Previous GDM, strong FH, previous infant >9lbs

• High risk: Those not in very high risk or low risk category

Gestational Diabetes-Screening

• Low Risk (all of following)

• Age <25 years

• Weight normal before pregnancy• Member of an ethnic group with a

low prevalence of diabetes

Diabetes Care 31(S1) 2008

• Low Risk (all of following)(cont’d)• No known diabetes in first-degree

relatives

• No history of abnormal glucose tolerance

• No history of poor obstetrical outcome

Gestational Diabetes-Screening

Diabetes Care 31(S1) 2008

Gestational Diabetes Screening

• 2 step approach

oral glucose tolerance test (OGTT)

• 1) 50gm 1 hour OGTT

• 2) 100gm 2 hour OGTT

Gestational Diabetes-Screening

• GDM screening at 24–28 weeks:

• Two-step approach: – 1) Initial screening: plasma or serum

glucose 1 h after a 50-g oral glucose load

– Glucose threshold – 140 mg/dl identifies 80% of GDM– 130 mg/dl identifies 90% of GDM

Diabetes Care 31(S1) 2008

Gestational Diabetes-Screening• GDM screening at 24–28 weeks:

• Two-step approach (cont’d)

• 2) 3 hour OGTT*

(100g glucose load) Fasting: >95 mg/dl (5.3 mmol/l)

1 h: >180 mg/dl (10.0 mmol/l)2 h: >155 mg/dl (8.6 mmol/l)3 h: >140 mg/dl (7.8 mmol/l)

*2 of 4 Diabetes Care 31(S1) 2008

Gestational Diabetes Management

• Dietician

• Diabetes Educator

• Consider referral to Diabetologist or Endocrinologist

• Moderate Physical Activity ~30 minutes daily when appropriate

Summary and Recommendations of the Fifth International Workshop-Conference on Gestational Diabetes Mellitus

Diabetes Care 30:S251-S260, 2007

Glucose Control in GDM

• Preprandial: <95 mg/dl, and either:

1-h postmeal: <140 mg/dl

or2-h postmeal: <120 mg/dl

and Urine ketones negative

Summary and recommendations of the Fourth International Workshop-Conference on Gestational Diabetes Mellitus. The Organizing Committee. Diabetes Care 21(2):B161–B167, 1998

Gestational Diabetes-Medications

• Patients who do not meet metabolic goals within one week or show signs of excessive fetal growth

• Insulin has been the usual first choice

• Sulfonylureas (glyburide) may be used in select patients

• Other diabetes medications not recommended in GDM

Summary and Recommendations of the Fifth International Workshop-Conference on Gestational Diabetes Mellitus Diabetes Care 30:S251-S260, 2007

Langer et al N Engl J Med 343:1134–1138, 2000

Diabetes MedicationsInsulins-Safety

• Aspart, Lispro, NPH, R, Lispro protamine all Category B and used in pregnancy

• All other insulins Category C

• Human Insulins-Least Immunogenic

• Breastfeed-All insulins considered safe

Data from Package Inserts

Gestational Diabetes-Management

• Fasting, pre-meal, 2-hour post-prandial blood glucose probably all important

• Mean blood glucose >105-115, greater perinatal mortality

• A1C in GDM probably not important Am J Obstet Gynecol 192:1768–1776, 2005

ADA Position StatementPettit, et al Diabetes Care 3:458–464, 1980 Karlsson, Kjellmer Am J Obstet Gynecol 112:213–220, 1972Langer, et al Am J Obstet Gynecol 159:1478–1483, 1988

Insulin Dosing-GDM• Insulin dosing:• Can use usual weight based dosing

(i.e., 0.5 u/kg)• Practical dosing can be to start

10 units NPH with evening meal• Most will titrate to BID, with eventual

addition of Regular or Rapid Acting BID

Alternate Insulin Dosing in GDM

• Regular or rapid acting (lispro or aspart) with meals, NPH at bedtime

• NPH + Regular or rapid acting in AM, regular or rapid acting at supper, NPH at bedtime

• Titrate insulin based on SBGM values, tested fasting, pre-meal, 2 hour post-meal, bedtime, occasional 3 AM.

Gestational Diabetes Complications

GDM Complications

• Macrosomia • Fractures • Shoulder dystocia• Nerve palsies (Erb’s C5-6)• Neonatal hypoglycemia• Pregnancy outcomes can be very

poor with HTN/nephropathyGabbe, Obstetrics: Normal and Problem Pregnancies 2002

Gestational Diabetes:Outcomes

• Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) Study 28,000 women

• Four primary outcomes:

1) weight above the 90th percentile for gestational age

2) primary cesarean delivery

3) clinical neonatal hypoglycemia

4) cord-blood serum C-peptide level above the 90th percentile (fetal hyperinsulinemia)

NEJM (358) 2008

• Hyperglycemia and Adverse Pregnancy Outcomes (HAPO)

• Five secondary outcomes

1)premature delivery (before 37 weeks)

2)shoulder dystocia or birth injury

3)need for intensive neonatal care

4)hyperbilirubinemia

5)preeclampsia

Gestational Diabetes:Outcomes

NEJM (358) 2008

HAPO Primary and Secondary Outcomes

NEJM (358) 2008

Gestational Diabetes: Post-natal

• GDM is a prediabetes syndrome

• Some women will have frank type 2 diabetes presenting in pregnancy

• Blood glucose testing first few days after delivery

Kitzmiller, et al Diabetes Care 30:S225-S235, 2007

GDM Post-natal and Long Term Followup

Gestational Diabetes: Post-natal

• Fasting glucose rechecked 6-12 weeks following delivery

• Every 6 months thereafter to be screened for type 2 diabetes

• Higher risk of developing Type 2 Diabetes

Kitzmiller, et al Diabetes Care 30:S225-S235, 2007

Case Study

• 28 y/o caucasian female

• 2nd pregnancy

• 1st pregnancy at age 22, term male infant, 10 lbs 2oz, normal delivery

• “Thinks had high blood sugar”

• Very high risk (>9 lb infant, possible GDM)

Case Study• No other significant medical history No tobacco• Physical Exam: VS normal

5’ 2”

210 lbs

BMI 38.4

Remainder consistent with 12 weeks gestation

Case Study

• 26 weeks, no problems, maybe slightly large for dates

• 12 lb weight gain

• Went directly to 3 hour GTT (100g)

Case Study

• FBG: 94 ( > 95)

• 1 hour: 192 (>180)

• 2 hour: 160 (>155)

• 3 hour: 149 (>140)

• 3 of 4 values abnormal= GDM

Case Study

• Referred to Diabetes Educator and Dietician

• SMBG: FBG, pre-meal, 2 hour post-prandial, HS, 3 am prn

• Meal Plan

• No contraindications to exercise, encouraged to walk 15 min/daily

Glucose Control in GDM

• Preprandial: <95 mg/dl, and either:

1-h postmeal: <140 mg/dl

or2-h postmeal: <120 mg/dl

and Urine ketones negative

Summary and recommendations of the Fourth International Workshop-Conference on Gestational Diabetes Mellitus. The Organizing Committee. Diabetes Care 21(2):B161–B167, 1998

Case Study

• Returns one week later

• Has been following meal plan “90% of time”

• Has walked 15 minutes 2 times

• Has 4 FBG > 100

• 6 other values above target

Case Study

• Referred to Diabetes Educator for insulin start

• NPH 10 units, 3 units Insulin aspart BID

• Phone followup q 3 days

• Continues appropriate clinic appointments

Case Study

• 1-2 SMBG values out of target 1st week

• 3 weeks later, FBG, 2 hour post lunch and 2 hour post supper elevated about ~50% of time

• NPH increased in PM (or could move to HS), insulin aspart added at lunch (2 or 3 units) and increased at supper

Case Study• Normal vaginal delivery at 38 weeks

• 8lb 10oz healthy female infant

• Patients FBS day after delivery 90

• Enrolled in Diabetes Prevention Program

• Converted to type 2 diabetes 2 years later

• Had lap-band 4 years later

Gestational Diabetes Mellitus

Risk of Type 2 Diabetes• Meta analysis: 20 studies 675,455 women

• 7-fold increase in risk of type 2 diabetes following gestational diabetes vs. normoglycemic pregnancy

• Post pregnancy surveillance important

Bellamy, L. et al. Lancet, 2009, 373(9677): 1773-9

5 Reasons to perform glucose tolerance testing

after pregnancies complicated by GDM:• 1) The substantial prevalence of glucose abnormalities

detected by 3 months postpartum.

• 2) Abnormal test results identify women at high risk of developing diabetes over the next 5–10 years (15-50% risk)

• 3)Ample clinical trial evidence in women with glucose intolerance that type 2 diabetes can be delayed or prevented by lifestyle interventions or modest and perhaps intermittent

drug therapy.

Kitzmiller, et al Diabetes Care 30:S225-S235, 2007Kim et al Diabetes Care 25:1862-1868, 2002Lauenborg, et al Diabetes Care 27:1194-1199, 2004

5 Reasons to perform glucose tolerance testing

after pregnancies complicated by GDM: cont’d

• 4) Women with prior GDM and IGT or IFG have CVD risk factors. Interventions may also reduce subsequent CVD, which is the leading cause of death in both types of diabetes. GDM 71% higher risk of future CVD-other risk factors (HTN, lipids, smoking) assessed and managed

• 5) Identification, treatment, and planning pregnancy in women developing diabetes after GDM should reduce subsequent early fetal loss and major congenital malformations.

Kitzmiller, et al Diabetes Care 30:S225-S235, 2007Shah, et al Diabetes Care 31:1668-1669, 2008

Type 2 Diabetes Prevention

• Lifestyle- over 50% reduction of future type 2 diabetes

• Bariatric (Lap-Band-future preg?)- strong consideration in BMI >40 or >35 with co-morbid conditions

• Future treatments/prevention- no current medication role, possible in future

Diagnosis GuidelinesCategory FPG (mg/dL)

Normal <100Impaired Fasting Glucose (IFG)100 – 125

Diabetes >126**

•OR A1C >6.5

•** On 2 separate occasionsAmerican Diabetes AssociationAmerican Diabetes Association

Initial Type 2 Diabetes Treatment

• Current guidelines (ADA/EASD, AACE) recommend metformin at diagnosis in additional to lifestyle management

• Diabetes Educator/Dietician

• Eye Exam

• Evaluation of cholesterol and blood pressure

Key References• Summary and Recommendations of the Fifth International Workshop-

Conference on Gestational Diabetes Mellitus

Diabetes Care July 2007 30:S251-S260• American Diabetes Association Consensus Statement Pre-

existing DM in Pregnancy

Diabetes Care May 2008 vol. 31 no. 5 1060-1079 • American Diabetes Association: Clinical

Practice Recommendations:

http://care.diabetesjournals.org/content/33/Supplement_1 2010• International Diabetes Federation:

http://www.idf.org/global-guideline-pregnancy-and-diabetes 2009

Summary• GDM: Meet targets, avoid hypoglycemia,

reduce risk of complications

• GDM is a pre-diabetes syndrome

• Many women with GDM will go on to have repeat GDM or type 2 DM and have CVD risk

Acknowledgements

• William Zaks, M.D., Ph.D.,

Assistant Medical Director

Altru Diabetes Center

Grand Forks, ND

Slide and Content Review

Contact Info/Slide Decks/Media

e-mail

eric.l.johnson@med.und.eduejohnson@altru.org

Phone701-795-2861 or 701-777-3811

Slide Decks (Diabetes, Tobacco, other)http://www.med.und.edu/familymedicine/slidedecks.html

iTunes Podcasts (Diabetes)http://www.med.und.edu/podcasts/ or iTunes>>search UND Medcast (1/21/10 release)

WebMD Page:http://www.webmd.com/eric-l-johnson

Diabetes e-columns (archived):http://www.ndhealth.gov/diabetescoalition/DrJohnson/DrJohnson.htm