II. Precautions
- Type II Diabetes Screening guidelines vary by organization (e.g. ADA, USPTF, AAFP, ACOG, AAP)
- Early detection of Prediabetes may delay development of Type II Diabetes Mellitus
- However, Type II Diabetes detection does not alter mortality within first 10-20 years
- Screening for Type II Diabetes in age >70 years should be individualized based on life-expectancy and quality of life
- Routine screening for Type I Diabetes is not recommended
- Type I Diabetes presents with acute onset of symptoms (contrast with often asymptomatic Type II)
- Type I Antibody tests (e.g. GAD-65, C-peptide) do not have established cut-off values
- No established management strategy for asymptomatic Type I Diabetes prior to Hyperglycemia
III. Indications: Diabetes Screening in children (every 2 years starting at age 10 years or Puberty)
- See Type 2 Diabetes Mellitus in Children
- BMI or weight over 85% or more than 120% over Ideal Weight
- Two of the following risk factors
- Family History of diabetes in first or second degree relative
- High risk ethnicity (black, native american, native alaskan, asian, hispanic, pacific islander or native hawaiian)
- Signs or symptoms of Insulin Resistance
- Acanthosis Nigricans
- Hypertension
- Dyslipidemia (especially elevated Triglycerides, HDL Cholesterol)
- Polycystic ovarian disease
IV. Indications: Diabetes Screening in adults (every 3 years starting at age 45 years, every 1 year for high risk patients)
- Screen if Body Mass Index (BMI) >25 and one additional risk factor below
- Age 35 to 70 years old (USPTF decreased from age 40 years)
- Physical inactivity
- Family History of diabetes (especially first degree relative)
- High risk ethnicity (black, native american, native alaskan, asian, hispanic, pacific islander or native hawaiian)
- Prior Gestational Diabetes Mellitus (or newborn >9 pounds)
- Hypertension
- Cardiovascular disease history
- Dyslipidemia
- HDL Cholesterol <35 and
- Serum Triglycerides >250 mg/dl
- History of Impaired Glucose Tolerance
- Polycystic ovarian syndrome (PCOS)
- Clinical findings suggestive of Diabetes Mellitus (e.g. Acanthosis Nigricans)
V. Indications: Pregnancy
- Universal screening after 24 weeks gestation in all pregnant women (see Gestational Diabetes)
- First trimester Gestational Diabetes indications (ACOG, ADA)
- Type II Diabetes Mellitus risk factors
- Obesity
- Advanced maternal age >35 years old
- Prior history of Gestational Diabetes
- High risk ethnicity (black, native american, native alaskan, asian, hispanic, pacific islander or native hawaiian)
VI. Interpretation: Findings suggestive of Diabetes Mellitus (two of the following, or repeat testing)
- See Diabetes Mellitus
- Random Serum Glucose
- Serum Glucose over 200 mg/dl with symptoms
-
Fasting Serum Glucose
- Serum Glucose exceeds 126 mg/dl on 2 different days
- Postprandial Glucose (2 hours post meal)
- Serum Glucose over 200 mg/dl
- Precedes Fasting Glucose increase
- More predictive of Diabetes Mellitus Complications
- Casual Plasma Glucose (random Glucose)
- Same criteria as postprandial Glucose
- Oral Glucose Tolerance Test (OGGT)
- Two hour Glucose Tolerance Test (75 gram) >200 mg/dl
- Consider in patients with Insulin Resistance
- Patients with pre-diabetes to qualify for education
-
Hemoglobin A1C
- Hemoglobin A1C >6.5%
VII. Interpretation: Findings suggestive of Prediabetes or Impaired Glucose Metabolism
- See Prediabetes
- Hemoglobin A1C 5.7 to 6.4%
-
Fasting Glucose: 100 to 125 mg/dl
- Known as Impaired Fasting Glucose
- New guidelines suggest bottom cut-off of 100 mg/dl
- Metabolic Syndrome defined as 110 mg/dl or higher
-
Two hour Glucose Tolerance Test (75 g): 140-199 mg/dl
- Known as Impaired Glucose Tolerance
VIII. References
- Vail (2012) AAFP Board Review Express, San Jose
- Pippitt (2016) Am Fam Physician 93(2): 103-9 [PubMed]