Download - Management of Diabetes in Pregnancy

May 22, 2009
Gestational Diabetes
Update
Leigh Caplan RN CDE
Marsha Feldt RD CDE
SUNDEC - Diabetes Education Centre
Learning Objectives
• Review physiology of pregnancy and gestational
diabetes
• Review CDA clinical practice guidelines for
diagnosis and management of gestational diabetes
• Highlight nutrition therapy approaches
• Discuss role of hospital based gestational diabetes
programs
• Discuss post partum considerations for diabetes
risk and prevention
Case study:
Sue comes to see you for nutrition
counselling
• 32 years old, BMI 25
• family history of type 2
• G1P0 26 wks gestation
• Informs you she just received the diagnosis of
gestational diabetes
• GTT results - 5.1, 10.7, 9.1
What do you do?
Gestational Diabetes
• Definition:
Hyperglycemia with onset or first
recognition during Pregnancy
• Prevalence
3.7% in non-aboriginal
8-18% in aboriginal populations
CDA CPG 2008
Physiology in Late Pregnancy
• Characterized by accelerated growth of the
fetus
• A rise in blood levels of several
diabetogenic hormones
• Food ingestion results in higher
and more prolonged plasma glucose
concentration
Physiology in Late Pregnancy
• Maternal insulin and glucagon do not
cross the placenta
• During late pregnancy a women’s basal
insulin levels are higher than non-gravid
levels
• Food ingestion results in a twofold to
threefold increase in insulin secretion
(Franz, M.J., 2001)
Physiology of GDM
• Gestational hormones
induce insulin
resistance
• Inadequate insulin
reserve and
hyperglycemia ensues
Gestational Diabetes
Fetal Risks
•
•
•
•
Macrosomia - shoulder dystocia and related complications
Jaundice
Hypoglycemia
No increase in congenital anomalies
Exposure to GDM in utero
• LGA children or those born to obese mother have a 7% risk of
developing IGT at 7-11 yrs age
• Breastfeeding may lower risk
CDA CPG 2008
Gestational Diabetes
Maternal Risks
• C-section
• Pre-eclampsia
• Recurrence risk of GDM is 30-50%
• 30-60% lifetime risk in developing IFG,
IGT or type 2 diabetes
CDA CPG 2008
GDM Screening
• All women should be screened for GDM
between 24-28 weeks
– vs. risk factor based approach which can
miss up to ½ the cases of GDM
• Women with multiple risk factors should
be screened in the first trimester
Risk Factors:
for first trimester screening
•
•
•
•
•
> 35 yrs
BMI > 30
Previous diagnosis of GDM
Delivery of a mascrosomic baby
Member of a high-risk population
– (Aboriginal, Hispanic, South Asian, Asian, African)
• Acanthosis nigricans
• Corticosteroid use
• PCOS
Diagnosis of Gestational
Diabetes
Gestational Diabetes
Screen (GDS)
Value
75 g OGTT
indicated
<7.8 mmol/L
no
7.8-10.2 mmol/L
yes
> 10.3 mmol/L
No - GDM
1 hr after 50g load of
glucose
Diagnosis of Gestational
Diabetes
75 g OGTT
• GDM = 2 or more
values greater than
or equal to
• IGT = single
abnormal value
Fasting
> 5.3
mmol/L
1 hr
> 10.6
mmol/L
2 hr
> 8.9
mmol/L
Management of Gestational
Diabetes
• Strive to achieve glycemic targets
• Receive nutrition counselling from an
Registered Dietitian
• Encourage physical activity
• Avoid ketosis
• If BG targets are not reached within 2
weeks then insulin therapy should be
started
Target Blood Glucose Values
for GDM
• Fasting/Pre-prandial:
3.8 – 5.2 mmol/L
• 1 hour
5.5 - 7.7
mmol/L
• 2 hour
5.0 - 6.6
mmol/L
Nutrition Therapy as treatment
for GDM
• A tool to achieve appropriate nutrition
and glycemic goals of pregnancy
• to normalize fetal growth and birth
weight
Medical Nutrition Therapy
for GDM
Definition:
A carbohydrate controlled meal plan
with adequate nutrition for appropriate
weight gain, normoglycemia, and the
absence of ketones
Clinical Outcomes
• Achieve and maintain normoglycemia
• Promote adequate calories for wt gain
in absence of ketones
• Consume food providing adequate
nutrients for maternal and fetal health
GDM Nutrition Controversies
• What is a healthy weight gain for an obese
woman with GDM?
• How far to manipulate energy intake?
• Does the balance of carbohydrate and fat
matter?
Excess Weight Gain
• May increase incidence of GDM in
future pregnancy
Obese women have larger babies
• More likely to develop macrosomia if
gain >25lb
• More likely to develop macrosomia with
high post prandial BG levels
Calorie Restricted Diets
• Avoid severe restriction - <1500 kcal not
recommended
• Avoid ketones
• 33% calorie restriction slowed wt gain
and improved BG – 1800 kcal
Role of Carbohydrate
• Carbohydrate can be modified to control
postprandial glucose elevations
• High fiber not associated with lower
glucose levels in GDM
• Lower carb intake (<42%) associated
with; less insulin; less LGA
• Postprandial correlated with %CHO at
meal; breakfast less tolerance
Emphasis for GDM
• Healthy Eating following CFG appropriate for
adequate weight gain
• DRI= minimum 175 g CHO/day
• Spacing of CHO into 3 meals & 2 to 4 snacks
• Smaller amounts of CHO at breakfast*
• Evening snack is important to prevent ketosis
overnight
• Encourage activity as tolerated
Carbohydrate Counting with
“Beyond the Basics”
• Canadian Diabetes Association meal
planning guide
• Based on Canada’s food guide groups
• Each food group outlines portion sizes of
various foods
• Each carbohydrate choice (grains/starch,
fruit, milk) = 15 grams carbohydrate
Grains – 8-10 choices
Fruit – 2-3 choices
Milk – 3-4 choices
Dietary Fat in GDM
• up to 40% of total energy intake during
pregnancy
• choose food source which are lower in
saturated and transfats
Artificial Sweeteners
When used within ADI
– Aspartame – does not cross placenta; no adverse
effects
– Sucralose (splenda) – acceptable
– Acesulfame potassium – acceptable
• Saccharin – crosses placenta; not acceptable
• Cyclamates – not acceptable
Back to Sue
3 weeks later
• Trying to work with meal plan
• Weight has been stable for 3 weeks
• Blood glucose readings:
– Fasting 5.0 to 5.7
– 2 hours pc breakfast 4.6 to 5.3
– 2 hours pc lunch 5.7 to 6.5
– 2 hours pc dinner 7.2 to 7.9
What do you discuss with Sue?
Purpose of Insulin
• To achieve plasma glucose control nearly
identical to those observed in women without
diabetes
• Must be individualized
• Insulin requirements will
change with various
stages of gestation
(ADA. Medical Management of Pregnancy
Complicated by Diabetes., 2000)
Types of Insulin
Approved in pregnancy
• Fast acting: Humalog , NovoRapid
• Short acting: Regular/R
• Intermediate acting: NPH/N
– Detemir can be used if woman unable to tolerate
NPH ( Ongoing study to evaluate use in
pregnancy)
– Glargine – avoid use
Devices for Insulin Delivery
Considerations for Adjusting
Insulin
• Look for patterns in blood glucose readings
• Adjust for hypoglycemia first
• Then adjust for high blood glucose
Can oral hypoglycemia agents be
used to treat GDM?
• Glyburide
– Does not cross the placenta
– Controlled BG in 80% of women
– Women with high FBG less likely to respond to
Glyburide
– More adverse perinatal outcomes compared to
insulin
• Not approved in Canada
– use is considered off-label and requires
appropriate discussions of risks with patient
CDA CPG 2008
Metformin
– alone or with insulin was not associated with
increased perinatal complications compared with
insulin
– Less severe hypoglycemia in neonates
– Does cross the placenta – long term study MiG
TOFU ongoing
• Not approved in Canada
– use is considered off-label and requires
appropriate discussions of risks with patient
NEJM, 2008
Postpartum Physiology:
Once the placenta is delivered:
• Hormones clear from circulation
• They will be monitored in hospital if
blood glucose remains elevated may
require medications
Postpartum Focus:
• Encourage follow up with health care
provider to have
– OGTT (6 weeks to 6 months 75 g OGTT)
– weight management,
– postpartum visit with a registered dietitian
– Encourage breastfeeding
– Monitoring occasionally with meter
– Future pregnancy
Breastfeeding and DM meds
• Both metformin and glyburide/glipizide
are found at low concentrations (or not
at all) in breast milk
– Hale et al, Diabetologia 2002
– Feig et al, Diabetes Care 2005
– Can be considered however, more longterm studies needed
SUNDEC– Diabetes Education
Centre
(416) 480-4805
• Multidisciplinary team of health
professionals ( RN, RD)
• Self referral
• Individual counselling
• Group education classes
• Type 2, Pre-diabetes, Diabetes
Prevention and Seniors programs
Case 2
Justine
Justine was diagnosed with gestational diabetes at 20
weeks,
– pre-preg BMI = 28.7, GTT results were: 6.2, 10.2, 9.8
She is now at 25 weeks
• FBS 6.1 – 7.4
• 3 meals and 1 -2 snacks.
– Diet history: Oatmeal at breakfast, lunch and dinner consist
of aprox. ½ cup rice, lots of vegetables and meat, in the
afternoon a piece of fruit, 2 cups of milk at bed
• What would you do?
www.diabetes.ca
Resources and References
Canadian Diabetes Association: www.diabetes.ca
-Recommendations for Nutrition Best Practice in the
Management of GDM
-2003 Canadian Diabetes Association Clinical Practice
Guidelines for the Prevention and Management of
Diabetes in Canada
Nutrition for a Healthy Pregnancy: National Guidelines
for the Child Bearing Years
Healthy Eating is in Store for you:
www.healthyeatingisinstore.ca