Type 2 diabetes Flashcards
Overview, aetiology & pathophysiology, molecular action
What are the different types of diabetes?
- Type 1 (autoimmune destruction of beta cells)
- Type 2 (insulin resistance and beta-cell dysfunction)
- Gestational (develops in pregnancy)
- Type 3c (pancreatic-related)
- Type 1.5 (Latent Autoimmune Diabetes in Adults)
- Double (type 1 diabetes with significant insulin resistance)
- Neonatal (infants 6 months old)
- Steroid induced (cause hyperglycaemia, make liver less sensitive to insulin)
- Monogenic (GCK, HNF1a, HNF4a, HNF1b) - mutation in a single gene
What are the syndromic forms of diabetes?
Alström Syndrome (genetic disorder causes obesity, organ dysfunction and health issues) (type 2 diabetes is a symptom)
Wolfram Syndrome (genetic disorder affecting body’s systems (diabetes mellitus due to a lack of insulin or diabetes insipidus cannot concentrate urine)
Glucagonoma Syndrome (pancreatic tumour secretes too much glucagon (raising blood sugar)
Pheochromocytoma Syndrome (tumour in adrenal gland producing too much catecholamines like adrenaline and noradrenaline, can manifest as impaired glucose tolerance as interferes with insulin production)
Why is diabetes a growing problem in the UK?
5 million people live with diabetes (1 in 14 individuals)
In some constituencies, prevalence reaches 1 in 9
Prevalence: 9% rise in 2018 and 13% rise in 2023
Major weekly impact: 185 amputations, 700 strokes, 2,000 heart attacks and 500 early deaths
What are the risk factors for type 2 diabetes?
Non-modifiable
Modifiable
Emerging factors
- Family Hx, ethnicity, age, Hx of gestational diabetes, gender
- Obesity, diet and physical inactivity, high blood pressure, smoking & alcohol use, sleep disorders and chronic stress
- Gut microbiome imbalance and Polycystic Ovary Syndrome (PCOS)
How is type 2 diabetes diagnosed?
Symptoms: Polyuria, polydipsia, fatigue, weight loss, blurred vision, gento-urinary and skin infections, DKA symptoms
Blood tests: HbA1C >48 mmol/mol (measure of 3-month glucose control)
Traditional x2 to confirm diagnosis
Random plasma blood glucose
Fasting Plasma Glucose (FPG) >7 mmol/L
Oral Glucose Tolerance Test (OGTT)
Caveats: HbA1C not suitable for acutely ill patients or those with abnormal haemoglobin.
What are the complications of diabetes?
Macrovascular: Cardiovascular disease, stroke, peripheral arterial disease (PAD)
Microvascular: Retinopathy, neuropathy, nephropathy
Acute: Diabetic ketoacidosis (DKA), hyperosmolar hyperglycaemic state (HHS)
What treatments are available for diabetic retinopathy?
Fenofibrate
Laser therapy
Monoclonal antibodies (e.g. Bevacizumab)
Implantable steroid treatments
Surgery for advanced cases
How does PAD (peripheral arterial disease) relate to diabetes and treatment?
12-20% of people aged >65 have PAD
Diabetes increases PAD risk, raising cardiovascular event risk 4-5 fold
Symptoms include leg cramps, cold extremities, and discolouration
Treatments: Clopidogrel, angioplasty, bypass surgery
What are the types of diabetic neuropathy and treatment?
Sensory neuropathy: Tingling, numbness, “pins and needles”
Autonomic neuropathy: Gastroparesis, bladder dysfunction, erectile dysfunction
Motor neuropathy: Muscle weakness, leading to falls
Treatment: Medications include duloxetine, gabapentin, pregabalin, and lidocaine plasters
What causes diabetic nephropathy and prevention?
High blood glucose damages renal blood vessels
Leads to albuminuria and reduced filtration
Prevention: control glycaemia, blood pressure, and lipids or use ACE inhibitors, ARBs, or SGLT2 inhibitors
What lifestyle changes can help manage type 2 diabetes?
Diet: Avoid “diabetic foods,” swap to low-GI alternatives, monitor labels
Exercise: 150 minutes of moderate aerobic activity weekly (e.g., brisk walking, cycling)
Weight management: Engage with weight loss programmes (e.g., Slimming World)
Strength training: Particularly beneficial for glucose metabolism
What is diabetic gastroparesis and how is it managed?
Symptoms: Nausea, vomiting, bloating, early satiety, weight loss
Diagnosis: Imaging (barium swallow) and endoscopy
Management:
First: Dietary adjustments
Second: Prokinetic medications (e.g., erythromycin, domperidone)
Third: Surgical interventions (e.g., gastric stimulation)
What are the exercise guidelines for people with diabetes?
Aerobic exercise: 150 minutes per week (e.g., brisk walking, water aerobics)
Vigorous exercise: Running, cycling uphill, skipping
Strength training: Builds muscle, improves glucose control
Tips: Make it social and realistic, plan ahead
How can type 2 diabetes be prevented?
Screen at-risk populations using:
- BMI assessments
- Blood tests (FPG, HbA1C)
Focus on lifestyle interventions:
- Healthy eating habits
- Physical activity
- Weight reduction
Regular monitoring for high-risk groups
Type 2 prevention strategies eligibility
Adults aged 40-74
Adults 25-39 from high-risk ethnics
Adults with high-risk co-morbidities (CVD, HTN, Non-Alcoholic Fatty Liver Disease, PCOS, obesity, Gestational Diabetes Mellitus, stroke & mental health illness/treatments)
Type 2 diabetes assessment outcomes:
Possible diagnosis
What A1c means
- FPG>7, A1C>48mmol/mol, refer to GP for additional testing
- If A1c>48 & diabetes symptoms present = T2DM
If A1c>48 & symptoms not present = repeat A1c in 3 months
If FPG >7 test A1c to confirm (<48 ‘high risk’ and act accordingly) (>48 diagnose T2DM)
Type 2 diabetes assessment outcomes:
Low risk
Moderate risk
High risk
- Brief advice
- High risk score with normal blood glucose/A1c, brief intervention & re-assess A1c or FBG every 3 yrs
- High risk score with ‘pre-diabetes’ A1c or raised FBG, refer to local lifestyle change programme, provide further info and contacts for healthcare, re-assess A1c or FBG annually
What is HbA1c? How does it work?
- Glycated haemoglobin, measures % of haemoglobin in RBCs that are coated with glucose
- Glucose in blood binds to Hb in RBCs, level of glyctaed Hb increases when glucose consistently high
Limitations of HbA1c testing
Conditions affecting RBC turnover: anaemia, recent blood transfusions, haemoglobinopathies (sickle cell)
Acute conditions: sudden onset of diabetes symptoms (<2 months), recent severe illness
Other: CKD, medication (steroids)
Type 2 diabetes diagnostic measures and what they are?
HbA1c
Fasting plasma glucose (FPG): blood glucose after an 8 hour fast
Oral glucose tolerance test (OGTT): measures glucose 2 hours after glucose solution
Random plasma glucose: useful in symptomatic patients
Type 2 diabetes pathophysiology:
Normal glucose homeostasis
Pathogenesis of T2DM
Factors contributing to hyperglycaemia
- Overview of insulin action, glucose uptake & regulation by pancreas, liver & muscle
- Insulin resistance: mechanism at cellular level (adipose tissue, liver and muscle)
Beta-cell dysfunction: progressive loss of pancreatic beta-cell function
Role of incretin hormones (GLP-1 & GIP) - Increased hepatic glucose production, reduced glucose uptake by peripheral tissues & increased lipolysis & free fatty acid levels
Who is HbA1c not suitable for?
Symptoms for <2 months
High diabetes risk and acutely ill
Treatment causing hyperglycaemia
Acute pancreatic damage
End-stage chronic kidney disease
HIV patients
Who is HbA1c a caution for?
Abnormal Hb
Anaemia
Altered RBC lifespan
Recent blood transfusion
Diabetic retinopathy:
Nonproliferative
Proliferative
- Haemorrhage, cotton wool spots, macular oedema, microaneurysm
- Abnormal blood vessel growth