Diabetes Flashcards
What are the metabolic effects of insulin and glucagon?
Insulin = bind to insulin receptor to increase GLUT4 receptors on cell; powers the Na+/K+ transporter Glucagon = breakdown glycogen
Where are insulin and glucagon produced?
Islets of Langerhans in the pancreas; Insulin (beta cells); glucagon (alpha cells)
What are the defining features of T1DM?
10% of DM population; Cell-mediated immune response to beta cells; often associated with HLA dysfunction
What are the symptoms of hyperglycaemia?
Weight loss, hungry and thirsty, glycosuria and polyuria; frequent infections, blurry vision, lethargy.
What is the pathophysiology of DKA?
Relative starvation causes lipids and ketones to be metabolised. Ketones are active acids; causing acidosis
What are the symptoms of DKA?
Kussmaul respiration (deep/laboured breathing; often fruity) + nausea/vomitting + mental status changes + cerebral odema
What are the signs of DKA?
Hyperkalemia + high anion gap + dehydration + high BSL
What is the mainstay of treatment for DKA?
Fluids + Insulin + K+ supplementation
What is the pathophysiology of T2DM?
Insulin resistance; body makes insulin but doesnt respond to it causing beta cell hyperplasia and hypertrophy (unsustainable). Exact pathophysiology not well understood.
What are common risk factors for T2DM?
- Obesity
- Hypertension
- Lack of exercise
- Genetic factors/ FHx
- Maternal/personal gestational DM
- Drugs (e.g. steroids)
- PCOS
Define HHS/HONK
Hyperosmolar hyperglycemic state/ hyperosmotic nonketotic coma: increased osmolarity from dehydration due to hyperglycemia (an osmotically active compound)
What are the signs of HHS?
Mild ketonemia and acidosis (not to extent of DKA); NO anion gap.
What are the symptoms of HHS?
Mental status changes, coma
What are the diagnostic cut offs for diabetes?
2x Fasting glucose >7mmol/L 2 hour post prandial glucose >11mmol/L HBA1C >50 Urine/plasma ketones
Describe some lifestyle treatments for T2DM
- Losing weight ~5% TBW = VERY LOW CALORIE
- Healthy diet (less sugary beverages/saturated fats)
- Exercise at least 30 min a day/5 days a week
- Quit smoking
What is the generalised treatment pathway for T2DM?
Trial lifestyle intervention for at least 3 months + metformin (first line); followed by other oral agents. Consider CVR and manage other cardiac risk factors aggressively. Monitor for complications and ensure adequate follow up and review.
What are the foundations for insulin therapy for T2DM?
- Should be considered if HBA1C >75 despite PO meds
- Risk of hypoglycemia
- Start with ~10IU isophane (intermediate acting insulin) OD/BD
- Titrated with effect, need to ensure moving injection site
Describe metformin
- Works by increasing peripheral insulin sensitivity
- Can cause nausea/diarrhoea and LACTIC ACIDOSIS; may reduce B12 absorption
- Reduce dose if CKD (GFR < 45); avoid if significant (<30)
- 500mg OD - BD with food; up to 3mg/day
- Withhold if acutely unwell
Describe sulfonylureas
- Glipizide (5mg BD for thin pts), gliclazide (40mg BD obese pts)
- Works by increasing pancreatic insulin production
- Can cause HYPOglycemia and weight gain
What are the symptoms of hypoglycemia?
Weakness, hunger, shaking, sweating, blurred vision, lightheadedness –> LOC, seizures, coma. Typically <4mmol/L
What is the treatment of hypoglycemia?
Sugar/food (e.g. 7-10 jellybeans) –> IV dextrose –> glucagon. Recheck after 5-10min. Repeat if neccessary.
What are the TOP 5 complications of uncontrolled diabetes?
Artherosclerosis ++ –> heart attacks, strokes, retinopathy, nephropathy and peripheral neuropathy and vascular disease
What are the signs of diabetic retinopathy?
Cotton wool spots, flare haemorrhages on fundoscopy, neovascularisation +/- blindness. Should be tested every 2 years.
What are the signs of diabetic nephropathy?
Initially microalbuminuria or ACR (30mg/day) –> proteinuria on dipstick. Treat with BP control (ACEi)
