Type 1 DM Flashcards
What is the etiology of T1DM?
Immune mediated in > 90% cases
Idiopathic in < 10% cases
What are the characteristics of T1Dm?
- Catabolic disorder characterized by
- Absent or extremely low circulating insulin
- Increased plasma glucagon
- Insufficient pancreatic beta cell response
A. Absent/low insulin secretion
What leads to hyperglycemia?
- Glucose acts as osmotic diuretic
A. Leads to polyuria and polydipsia
B. Caloric loss increases hunger (polyphagia)
Why is insulin required for T1Dm?
Reverse catabolic state
Prevent ketosis
Reduce hyperglucagonemia
Reduce blood glucose
What are the risk factors for Immune mediated T1Dm?
- Genetic
A. 33% of cases - Environmental factors
A. Scandinavian & Northern European ethnicity
What are the risk factors for idiopathic T1DM?
Usually African or Asian descent
Some cases have mutated PAX-4 gene
Essential gene in development of pancreatic islet cells
What are teh sxs of T1DM?
1. Polyuria A. Excessive urination B.. Osmotic diuresis 2. Polydipsia A. Excessive thirst B. Hyperosmolar state 3. Polyphagia A. Excessive appetite 4. Weakness or fatigue A. K+ loss & protein breakdown 5. Blurred vision A. Lens exposed to hyperosmolar state 6. Weight loss A. Initially due to depletion of water, glycogen and trigs B. Muscle wasting due to protein as energy source 7. Pruritis A. Hyperglycemia & dehydration 8. Peripheral neuropathy A. Neurotoxicity from sustained hyperglycemia
What are the Urinalysis results in T1Dm?
Glycosuria
Ketonuria
Ketones > 3 mmol/L requires hospitalization
What are the serum glucose results for T1DM?
- FBS 100-126 mg/dL → impaired (pre-diabetes)
- Random glucose or 2 hr GTT ≥ 200 mg/dL → DM
- If FBS ≥ 126 mg/dL, F/U with 2 hr GTT
What are the fasting lipid panel results for T1DM?
Triglycerides elevated
What other dx studies are used in T1DM?
- EKG
- BMP
A. BUN/Cr
B. Electrolytes - HbA1c
- Urine Microalbumin
- Urinalysis
What are the limitations of home glucose monitors?
- Older meters calibrated against whole blood concentrations
A. Displayed values are 10%-15% lower than plasma glucose - ↑ or ↓ Hct can alter glucose value
- Meters & test strips calibrate glucose 60-160 mg/dL
A. Accuracy not as good for low or high levels
What can cause falsely low glucose meter readings?
- critically ill pts on supplemental oxygen
A. Various chemstrips
B. Glucose oxidase (false readings)
C> Glucose dehydrogenase strips preferred in these pts
What are the ADA carb recommendations?
45-65% total calories
Count carbs to titrate insulin
What are the ADA fat recommendations?
25-35% with < 7% from sat fats
What are the ADA protein recommendations?
10-35%
What are the ADA cholesterol recommendations?
< 200 mg/day if LDL > 100 mg/dL
Why is dietary fiber important?
Slows nutrient absorption rates so glucose absorption is slower -> lowers hyperglycemia
Has favorable effect on cholesterol
What artificial sweeteners can be used for T1Dm?
- Splenda, Sweet ‘n Low, Truvia
A. Can be used in beverages, baking & cooking - Sugar alcohols
A. Sorbitol, Xylitol, Mannitol
B. Not as easily absorbed as sugar so they do not raise sugar levels as much
What is indicated for all T1DM?
Insulin
What are the recombinant Human insulins?
A. Humulin R (regular) & N (NPH)
B. Novolin R (regular) & N (NPH)
What are the analogs of human insulin?
A. Rapid acting – lispro/Humalog, aspart/NovoLog, glulisine/Apida
B. Long acting – glargine/Lantus, detemir/Levemir
What is the function of basal insulin?
- Suppresses glucose production between meals and overnight
- Mimics natural pancreatic basal insulin secretory patterns
- Continued effect over 24 hrs
What is the function of bolus insulin?
Limits hyperglycemia after meals
When might an intermediate acting insulin be dosed?
- Pre-breakfast blood sugar reflects adequacy of PM or HS dose
- Pre-dinner blood sugar reflects adequacy of AM dose
When might a rapid acting insulin be dosed?
- Pre-lunch glucose level reflects adequacy of fasting AM dose
- HS glucose level reflects adequacy of pre-prandial (PM) supper dose