Carbohydrates Tests for DM Flashcards
Screening for diabetes should occur
Every 3 years for adults ≥45 years old; every year for individuals with ≥1 risk factor
RPG (Random Plasma Glucose) test is used with
Symptoms of diabetes (3P) for diagnosis
RPG criteria for diagnosing diabetes is
≥200 mg/dL with symptoms of DM
Fasting Plasma Glucose (FPG) requires
At least 8 hours of fasting (only water allowed)
Normal FPG is
<100 mg/dL
Prediabetes FPG is
100-125 mg/dL
Diabetes FPG is
≥126 mg/dL (confirmatory)
2-hour Post-Prandial Plasma Glucose (OGTT) requires
CHO intake ≥150 g/day for 3 days prior to test
Fasting for 2-hour Post-Prandial Plasma Glucose (OGTT) test is
8-14 hours
Standard load for OGTT is
75 grams for adults, or 1.75g/kg body weight for children
Normal 2-hour Post-Prandial Plasma Glucose (OGTT) is
<140 mg/dL
Prediabetes 2-hour Post-Prandial Plasma Glucose (OGTT) is
140-199 mg/dL
Diabetes 2-hour Post-Prandial Plasma Glucose (OGTT) is
≥200 mg/dL
HbA1c specimen type is
EDTA whole blood
HbA1c test is
Not affected by meal or fasting
Prediabetes HbA1c is
5.7-6.4%
Diabetes HbA1c is
“≥6.5%”
Screening period for GDM in nondiabetic pregnant women
24-28 weeks of gestation
One-Step Method for GDM uses
75 g glucose load (2-hour OGTT)
One-Step Method FPG diagnostic criterion is
> = 92 mg/dL
One-Step Method 1-hour plasma glucose (PG) diagnostic criterion is
> = 180 mg/dL
One-Step Method 2-hour plasma glucose (PG) diagnostic criterion is
> = 153 mg/dL
Two-Step Method Step 1 glucose load is
50 g (1-hour OGTT)
Two-Step Method Step 1 diagnostic threshold to proceed to Step 2 is
> = 140 mg/dL
Alternative Two-Step Method Step 1 thresholds with greater sensitivity are
> = 130 or 135 mg/dL
Two-Step Method Step 2 glucose load is
100 g (3-hour OGTT)
Two-Step Method Step 2 FPG diagnostic criterion is
> = 95 mg/dL
Two-Step Method Step 2 1-hour plasma glucose (PG) diagnostic criterion is
> = 180 mg/dL
Two-Step Method Step 2 2-hour plasma glucose (PG) diagnostic criterion is
> = 155 mg/dL
Two-Step Method Step 2 3-hour plasma glucose (PG) diagnostic criterion is
> = 140 mg/dL
Positive result for Two-Step Method is defined as
2 out of 4 values meeting or exceeding the threshold
Whole blood glucose monitoring is commonly performed using
POCT devices at home or patient bedside
Frequency of blood glucose monitoring for Type 1 DM according to ADA
3-4 times daily
Comparison of whole blood glucose to plasma glucose levels
10-15% lower than plasma glucose
ADA glycemic goal for pre-prandial glucose
70-130 mg/dL
ADA glycemic goal for post-prandial glucose
<180 mg/dL
Definition of HbA1c
HbA with glucose irreversibly attached to one or both N-terminal valines of the β-chains
Duration HbA1c reflects average blood glucose
2-3 months (120-day RBC lifespan)
ADA glycemic goal for HbA1c
<7%
HbA1c value indicating poor glycemic control
> 12%
Equation to estimate Average Glucose (eAG) from HbA1c
eAG = (28.7*A1c) - 46.7
Definition of fructosamine
Glycosylated albumin reflecting glucose control over 2-3 weeks
Clinical use of fructosamine
Used when HbA1c is unreliable
Reference range for fructosamine
205-285 umol/L
Fructosamine is unreliable in patients with serum albumin level
≤3 g/dL
Microalbuminuria is an early indicator of
Diabetic nephropathy
Microalbuminuria diagnostic criteria
20-200 ug/min, 30-300 mg/24h, or albumin-creatinine ratio of 30-300 ug/mg
Microalbuminuria confirmation requires persistence in
2 out of 3 urine collections within 3-6 months
