T2 Diabetes mellitus & drug treatments Flashcards
Define T2DM
Biochemical results?
Condition of insulin resistance and beta cells cannot produce enough insulin to keep b/g normal
- Deficit in B cells/ increased b-cell apoptosis/ extracellular anyloid deposits derived from LADP
Glucuse ≥ 11.1 mmol/L + symptoms
Glucuse ≥ 11.1 mmol/L x2
HbA1c ≥ 48 mmol/mol (6.5%)
How would you diagnose T2DM if unsure (or in pregnant ladies)?
- 75g glucose tolerance test
DM if : fasting plasma glucose ≥ 7mmol/L; 2 hour plasma glucose ≥ 11/1 mmol/L - Impaired glucose tolerance
- 2 hour glucose 7-11 mmol/L - Impaired fasting glucose
- Fasting glucose between 6.6-9 mmol/L
- Excess fat in diabetic pancreas (as fat decreases, B cell function increases)
- Waist circumeference?
Consider the aetiology of T2DM
What could cause it
- Genetics contributing to reduced beta cell mass
- seen in high percentage of indentical co-twins
- polygenic
- fetal programming (epigenitic) - maternal hyperglycaemia, intrauterine growth retardation - B cell regression
- Old age
- Other pancreatic pathology
- Change in the gut microbiota
- Glucotoxicity and lipotoxicity
Which organs are disturbed due to the decrease in incretin?
Glucotoxicity and lipotoxicity leading to:
B cell in pancreas –> Insulin –> Fat, liver, muscle
Explain the link between epicardial fat and vascular disease
STRONG RISK FACTOR
- FFAs: atherogenic lipids, insulin resistance
- Cytokines: insulin resistance, inflammation
- Procoagulant factors (PAI1)
Discuss the epidemiology of T2DM
4.6 million plus a futhr 1.23 million at high risk
Related to obesity (which has increased in UK)- coprevalence is 70% of those ≥ 45
- Age group most likely to be obese 55-64 (however increasing in younger people)
What advice is given by healthcare professionals?
What are the side effects/ morbidity related to?
Keep a BMI<23, exercise, healthy diet
- Hyperglycaemia
- damages organs and nerves (cataracts )
- 1% decrease in HBA1c decreases cataracts risk by 19% - Dysregulation of lipid metabolism (bad for vaascular system)
- Maculopathy - Increased levels of proinflammatory cytokines
- Increased levels of free radicals
- Increased susceptibility to infection
** Can lead to haemodialysis for chronic renal failure
What is a neuropathic ulcer?
Nerve damage due to diabetes causes altered or complete loss of feeling in the foot and/or leg. This is known as peripheral neuropathy. Pressure from shoes, cuts, bruises, or any injury to the foot may go unnoticed. The loss of protective sensation stops the patient from being warned that the skin is being injured and may result in skin loss, blisters and ulcers.
Adverse side effects of T2DM
- Glycosylation of connective tissue e.g. Cheiroarthropathy
BONE
- mechanically weaker, doubles risk of farcture (in spite of normal bone density)
Neuropathis ulcer
State 4 consequences of dyslipidaemia and pro-inflammatory state
- CAD
- Lipoprotein classes and inflammation
- Atherosclerotic lesions
- Peripheral vascular disease
What lifestyle changes can be adopted to treat T2DM?
How can prevention and screening help?
Medications?
Diet, exercise, smoking cessation
Screen for complications and treat early
- Retinal photography –> laser treatment
- Measure kidney albumin (EMV), control BP, ACE inhibitors
- Screen for neuropathy and vascular disease
Reduces CV risk factors
Statins for hypertension caused by hyperglycaemia.
Biochemical goal of treatment?
LDL <2 mmol/; non- HDL chol <2.78
BP: 120-140/80
HbA1c 6.5-7.5% (48-58 mmol/mol)
- Must be indivually tailored: Strict adherance to guidelines for pregnant women and be cautious that giving elderly people ‘hypos’ –> falling
Outline the effects of insulin on
- hepatocytes
- myocytes
- adipocytes
- Decreased gluconeogenesis, glycogenolysis and ketogenesis
- Increased GLUT-4 translocation to membrane, glucose oxidation, glycogen synthesis, AA uptake, protein synthesis
- Decreased glycogenolysis, AA release - Increased glucose uptake, increased TG synthesis, decreased FFA’s and glycerol release
**NET EFFECT IS TO CAUSE HYPOGLYCAEMIA AND INCREASE FUEL STORAGE IN MUSCLE, FAT TISSUE AND LIVER
What can cause hyperglycaemia and which drug classification may exploit these mechanisms as therapetic sites?
- B- cell dysfunction
- Sulfunylureas, GLP-1 analogues, DDP-4 inhibitors - Loss of B-cell mass
- Insulin replacement - Diet/exercise
- Renal glucose absorption
- SGLT2 inhibitors - Peripheral insulin resistance
- Metformin, TZDs
CONSIDER THERAPUTIC TREATMENTS FOR T2DM
Sulfonylureas
- Examples?
- Route of administeration?
- Mechanism of action?
- Indication?
Gluclazide, glipizide, glimipinde
Orally active
Plasma protein bound
Cause the release of endogenous insulin in abscence of glucose by binding to ATP-sensitive K+ Channel (mimmicks effect of ATP)
Secondary MOA: Sensitize B-cells to glucose, decrease lipolysis, decreases clearance of insulin by the liver
Useful only in T2 DM
- Ideal patient (40+, DM for <10y, dailu insulin <40 units)
- Can be used in combination with other anti-diabetic drugs