Screening and Diagnosis in daibetes by diabetesasia.org

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Screening and Diagnosis
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Objectives

• At the end of this session you will be able to
• Define GDM
• Identify the risks for development of GDM.
• State the prevalence of GDM locally
• Explain the reason for identifying and treating
  GDM
• Identify appropriate screening measures
• Identify who should be screened
• Identify diagnostic criteria

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Definition

• Glucose intolerance with onset or first
  recognition during pregnancy
• Characterized by ß-cell function that is unable
  to meet the bodys insulin needs

Buchanan, Wiang, Kjos, Watanabe 2007
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Glucose regulation during pregnancy

• Insulin resistance begins in mid pregnancy and
  progresses through the third trimester
• A result of maternal adiposity and effects of
  placental hormones
• ß -cells usually make more insulin to compensate
  for resistance when they cannot meet the needs
  hyperglycemia occurs

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• GDM represents a state of chronic ß-cell
  dysfunction in the face of insulin resistance
• Insulin resistance and insulin levels are
  different prior to pregnancy in women who develop
  GDM and those who do not
• Changes in insulin sensitivity are similar in
  both groups during pregnancy
• However in GDM women, insulin secretion does not
  increase adequately

Buchanan, Wiang, Kjos, Watanabe 2007
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Prevalence

• The prevalence of GDM is estimated to be 10-16.9
  in pregnant women depending on the diagnostic
  criteria used.
• Prevalence also varies by region and ethnicity.
• Highest prevalence is in South East Asia
• Lowest in North America and the Caribbean
• Prevalence higher
• in less physically active women.
• In older women
• In women with higher BMI
• In those with a strong family history of diabetes

WHO, 2013 IDF, 2013
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Discussion

• What are the risk factors for gestational
  diabetes?
• What risk factors do you see most often in your
  setting?

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Risk factors for GDM
Low risk

• High risk

• Obesity
• Diabetes in 1st degree relative
• Previous
• history of GDM or glucose intolerance
• complicated pregnancy
• infant with macrosomia gt 3.5 kg
• Older age
• High risk ethnic group South Asian, East Asian,
  Indigenous American or Australian, Hispanic
• PCOS

• Age less than 25 years
• No previous poor pregnancy outcomes
• No diabetes in 1st degree relatives
• Normal prepregnancy weight and weight gain during
  pregnancy
• No history of abnormal glucose tolerance

Perkins, Dunn, Jagastia, 2007
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Is Hypertension a risk factor?

• Hypertension prior to pregnancy or during 1st
  trimester doubled the risk of GDM independent
  of maternal weight
• Hence all women with hypertension should be
  screened for GDM

Hedderson, Ferrara, 2008
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Why diagnose and treat GDM?

• Short term risks for the mother
• Development of gestational hypertension,
  worsening essential hypertension or development
  of preeclampsia
• Operative delivery - related to macrosomia
• Polyhydramnios
• Premature labour
• Long term risks for the mother
• Development of type 2 diabetes in next 10 years
  (30-60 depending on population)
• Development of cardiovascular disease

CDA, 2013 Metzger, Buchanan, et al. 2007
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Why diagnose and treat GDM?

• Short term risks for the baby
• Macrosomia
• Neonatal hypoglycemia
• Jaundice
• Preterm birth
• Birth injury
• Hypocalcemia/ hypomagnesimia
• Respiratory distress syndrome
• Long term risks for the baby
• Obesity
• Type 2 diabetes

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Importance of follow up

• Long term follow up studies have shown that most
  women with GDM will develop diabetes within the
  first decade after the pregnancy
• Testing after pregnancy is important - more about
  this later

Kim, Newton, Knopp 2002
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Screening

• Whom to screen
• When to screen
• How to screen

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Who to screen

• Some guidelines recommend screening all women at
  the first visit to rule out pre-existing type 2
  diabetes
• Most guidelines recommend screening all women for
  GDM at 24-28 weeks gestation.

ADA, 2015 CDA , 2013
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When to screen?First trimester

• Screening in 1st trimester
• - to rule out unidentified pre-existing
  diabetes
• Fasting plasma glucose gt126 mg/dl (7 mmol/L)
• or
• HbA1c gt6.5
• or
• Random gt200mg/dl (11.1 mmol/L)
• or
• 2hr value in OGTT gt200mg/dl (11.1 mmol/L)
• If overt diabetes is detected, it must be treated
  appropriately.

ADA, 2015
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When to screenScreening for GDM

• Screening should be done at 24-28 weeks
• Diagnosis based on a 75 gm glucose load given in
  fasting state
• GDM diagnosed when one or more of the following
  is present
• Fasting 92 - 125 mg/dl (5.0 6.9 mmol/L)
• 1 hour post 75 gm load gt180 mg/dl (10 mmol/L)
• 2 hour post 75 gm load gt153mg/dl (8.5 mmol/L)
• If woman tests negative, screening at 32 weeks
  also may be necessary in presence of high risks

World Health Organization, 2013
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Diagnostic criteria
WHO (2013) 1 or more IADPSG 1 or more ADA one step ADA two step
Fasting plasma glucose 5.1-6.9 mmol/L (92-125 mg/dl) gt5.1 mmol/L (92 mg/dl) gt5.1 mmol/L (92 mg/dl) 50-g glucose load (nonfasting) If 1 hour gt 7.8mmol/L (140mg/dl) Do 100 g OGTT GDM If 2 of 4 results high
1 hour PG after 75gm load gt10.0mmol/L (180mg/dl) gt10.0mmol/L (180mg/dl) gt10.0mmol/L (180mg/dl) 50-g glucose load (nonfasting) If 1 hour gt 7.8mmol/L (140mg/dl) Do 100 g OGTT GDM If 2 of 4 results high
2 hour PG after 75gm load 8.5-11.0 mmol/L (153-199 mg/dl) gt8.5 mmol/L (153 mg/dl) gt8.5 mmol/L (153 mg/dl) 50-g glucose load (nonfasting) If 1 hour gt 7.8mmol/L (140mg/dl) Do 100 g OGTT GDM If 2 of 4 results high

Diabetes Care 2015, WHO 2013
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How to screen

• Key considerations for screening in low resource
  countries
• Low cost
• No requirement for elaborate preparation
• High sensitivity and specificity
• Short turn-around time
• Be administered by health workers with minimal
  training
• Need little maintenance, calibration, or
  refrigeration

Agarwal et al, 2007
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Venous or capillary

• The venous plasma is the gold standard
• Where laboratory facilities or technicians are
  not available, capillary glucose estimations may
  be done using a hand held glucose meter.
• The glucose meter must be standardized with a lab
  and calibrated against the lab on a regular
  basis.

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Which of these women has GDM?

• All have had 75g glucose load at about 25 weeks
• Rupinder, overweight, 35 years old,
• fasting 90 mg/dl (5.0 mmol/L),
• 1 hr 170mg/d (9.4 mmol/L),
• 2hr 135mg/dl (7.5 mmol/L)
• Joanne, 3rd pregnancy, history of big babies,
• fasting 130 mg/dl (7.2 mmol/L),
• 1 hr 190mg/dl (10.5 mmol/L)
• 2 hr 220mg/dl (12.2 mmol/L)
• Maria, 1st pregnancy, 25 years old, obese,
• fasting 90mg/dl (5 mmol/L),
• 1 hr 168mg/dl (9.3mmol/L)
• 2 hr 160 mg/dl (8.8mmol/L)

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Giving the diagnosis

• Will my baby be ok? 1st question often asked
• Is this temporary? 2nd question
• Questions provide an opportunity for teaching
• Must answer truthfully
• Must convey importance of management during
  pregnancy for healthy outcome but also for future
  health of baby and mother
• Risk of type 2 diabetes
• Risk of obesity

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References

• American Diabetes Association. Clinical Practice
  Recommendations 2015. Diabetes Care. 201538(1)
• Agarwal et al - Fasting plasma glucose as a
  screening test for gestational diabetes mellitus,
  Archives of Gynecology and Obstetrics 2007
• Buchanan T, Xiang A, Kjos S, Watanabe R. What is
  gestational Diabetes? Diabetes Care
  200730(2)S105-111.
• Canadian Diabetes Association Clinical Practice
  Guidelines Expert Committee. Canadian Diabetes
  Association 2013 Clinical practice guidelines for
  the prevention and management of diabetes in
  Canada Diabetes and pregnancy. Can J of
  Diabetes. 201337(suppl 1)S168-183.
• Hedderson MM, Ferrara A. High blood pressure
  before and during early pregnancy is associated
  with an increased risk of gestational diabetes
  mellitus. Diabetes Care. 200831(12)2362-2367.
• IDF Diabetes Atlas 6th Ed, 2013
• Kim C. Newton KM, Knopp RH. Gestational diabetes
  and the incidence of type 2 diabetes. Diabetes
  Care 2002251862-1868
• Metzger BE, Buchanan TA, Coustan DR, De Leiva A,
  Hadden DR, Hod M. Summary and recommendations of
  the fifth international workshop-conference on
  gestational diabetes mellitus, Diabetes Care.
  200730(suppl 2)S251-260.
• Perkins JM, Dunn JP, Jagastia SM. Perspectives
  in gestational diabetes mellitus A review of
  screening, diagnosis and treatment. Clinical
  Diabetes. 200725(2)57-62
• WHO. Diagnostic Criteria and Classification of
  Hyperglycaemia First Detected in Pregnancy , 2013