DM: Patho, S&S, Diagnosis, Goals, Monitoring Flashcards
DM is a metabolic disorder can be characterized by ___________ or _____________, or both.
- Resistance to the action of insulin
- Insufficient insulin secretion
*Or both
List the different types of DM
Type 1
Type 2
Gestational
Others: infections, drugs (corticosteroids, immunosuppressants, antibiotics such as fluoroquinolones, HIV drugs), pancreas destruction, endocrinopathies
Describe the pathophysiology of T1DM
Absolute deficiency of pancreatic B-cell function
- Immune mediated destruction
- Positive antibodies
*Can be due to genetic and environmental factors
Name the autoantibodies associated with T1DM
- Islet cell autoantibodies
- Autoantibodies GAD (GAD65)
- Autoantibodies to insulin
- Autoantibodies to tyrosine phosphatases IA-2 and IA-2b
- Autoantibodies to zinc transporter 8 (ZnT8)
Describe the staging of T1DM
Stage 1:
- Positive antibodies
- Normoglycemia
- Presymptomatic
Stage 2:
- Positive antibodies
- Dysglycemia
- Presymptomatic
Stage 3:
- Positive antibodies
- New onset hyperglycemia
- Symptomatic
T1DM has long and variable clinical period, but mostly occurs in _____
Children
*If occur in late adult, known as latent autoimmune diabetes of adults
What is the relevance of C-peptide in DM
C-peptide is a byproduct released from proinsulin to form insulin
Absence of C-peptide signifies no insulin release from pancreas (Beta cells destroyed, likely T1DM)
What would C-peptide levels look like in T1DM and T2DM respectively
T1DM: absent
T2DM: normal or abnormal (since there is still some insulin secretion)
Why do we measure C-peptide levels instead of insulin levels?
C-peptide is measured because insulin has short half-life and is hard to measure
Describe the pathophysiology of T2DM
Progressive loss of adequate B cell insulin secretion, due to insulin resistance
=> Impaired glucose utilization
=> Increased hepatic glucose output
Decrease muscle glucose uptake => hyperglycemia => incr insulin secretion => hyperinsulinemia
Decrease liver glucose uptake => incr hepatic gluconeogenesis => hyperglycemia => incr insulin secretion => hyperinsulinemia
*Both GLUCOSE + INSULIN levels increase at early stage
*Can be due to lifestyle and genetic factors
What is the age of onset of T1DM vs T2DM
T1DM: <30yo, childhood onset
T2DM: >40yo, although increasing prevalence in obese children and young adults
T1DM has ____ onset of clinical presentation, while T2DM has ____ onset of clinical presentation
T1DM - abrupt (typically sudden high BG levels, diagnosed in hospital due to sudden ketosis episode)
T2DM - gradual
T1DM patients often have ____ physical appearance, while T2DM patients are often _____
T1DM: often thin
T2DM: often overweight
Ketosis frequently occurs in _____ due to?
Ketosis frequently occurs in T1DM (*uncommon in T2DM)
Ketosis occurs as a result of insulin deficiency causing lipolysis and metabolism of FFA which releases ketones
*Diabetic ketoacidosis (DKA) is an emergency!
What are the 5 syndrome in metabolic syndrome?
- Abdominal obesity
- Triglycerides
- HDL (low)
- Blood pressure
- Fasting glucose
=> 5 fold increase in CVD
=> Metbolic syndrome is abdominal obestity + any 2 of the other factors
What are the signs and symptoms of hyperglycemia?
- Extreme thirst (polydipsia)
- Frequent urination (polyuria)
- Dry skin/itchy skin
- Hunger (polyphagia)
- Blurred vision
- Drowsiness
- Decreased healing (impaired immune system)
Others:
- Tired
- Sexual problems
- Numb or tingling hands or feet
- Vagina infections
What are the signs and symptoms of hypoglycemia?
- Shaking, tremor
- Fast heartbeat
- Sweating
- Dizziness
- Anxious
- Hunger
- Impaired (blurry) vision
- Weakness, fatigue
- Headache
- Irritable
- Confusion
What are 4 parameters that can be used to measure DM?
- Fasting plasma glucose (FPG)
- No calorie intake for >=8h, e.g., in the morning
- Random or casual plasma glucose
- Any time of the day, regardless of meal
- Postprandial plasma glucose (PPG)
- Glucose levels measured 2h after meal (2h-PPG)
- Using a standardized 75g oral glucose tolerance test (OGTT)
- Hemoglobin A1c (HbA1c or A1c)
- Average amount of glucose in blood over the past 3 months
- Dependent on RBCs (low RBC => low HbA1c, high RBC => high HbA1c)
How is HbA1c related to FPG and PPG?
HbA1c = 3 month average of (FPG + PPG)
Basal/fasting and postprandial contributions to hyperglycemia:
- As HbA1c increases, basal/fasting contribution increases
(*Therefore basal insulin is initiated first, postprandial insulin is initiated if A1c still above goal despite basal dose >0.5IU/kg or FPG at goal)
Glucometers measure ______ and can be used to monitor hypo/hyperglycemia, adjust medications, monitor diet and exercise
Blood glucose levels (BG levels)
What should the frequency of measurements using glucometers?
Frequency varies depending on risk of hyperglycemia
High risk of hypoglycemia: T1DM, pregnant women, insulin pump users
- 4 times or more per day
- Before meals/snacks, at bedtime, at 3am
T2DM
- 3 times or more per day if on multiple injections of insulin (risk of hypo)
- For pts using less frequent insulin, noninsulin therapies, or medical nutrition therapy alone, SMBG useful to guide success of therapy
In practice
- check 2 times (once before breakfast FPG and once 2h after largest meal PPG)
- More frequent if self-titrating, changing therapies, ill
[DM DIAGNOSIS]
HbA1c cut off for diabetes is ____
HbA1c >= 7.0%
No further test required.
[DM DIAGNOSIS]
What HbA1c cut off determines that the patient is NOT diabetic?
HbA1c =<6.0%
No further test required, but can recommend if theres presence of clinical suspicion of diabetes
Recommended to repeat test in 3 years
[DM DIAGNOSIS]
If HbA1c is 6.1-6.9%, what does this determine?
It does not determine or diagnose anything!!!!!
If HbA1c 6.1-6.9%, further test (FPG or 2hOGTT) must be done
