Diabetes mellitus

Question 1

What is type I diabetes?

Answer 1

autoimmune response that triggers the destruction of insulin-producing β cells in the pancreas and results in an absolute insulin deficiency

Question 2

What is type II diabetes?

Answer 2

insulin resistance (insufficient response of peripheral cells to insulin) and pancreatic β cell dysfunction (impaired insulin secretion), resulting in relative insulin deficiency

Question 3

What are the risk factors of type 1 daibetes?

Answer 3

HLA association. HLA-DR3 and HLA-DR4 positive patients are 4–6 times more likely

Question 4

What are the risk factors of type 2 diabetes?

Answer 4

Obesity, high-calorie diet
High waist-to-hip ratio
Physical inactivity
First-degree relative with diabetes
Ethnicity 
Hypertension
Dyslipidemia

Question 5

What are the clinical features of type I diabetes?

Answer 5

Sudden onset diabetic ketoacidosis common first presentation 
Polyuria
Polydipsia 
Polyphagia
Weight loss

(Non-specific) Fatigue
Visual disturbances: blurred vision 
Calf cramps
Poor wound healing
Pruritus

Question 6

What are the clinical features of type II diabetes?

Answer 6

Gradual, commonly asymptomatic
(Hyperosmolar hyperglycaemic state) polyuria, polydipsia, nausea, vomiting, volume depletion (e.g., dry oral mucosa, decreased skin turgor), and eventually mental status changes and coma
Benign acanthosis nigricans

(Non-specific) Fatigue
Visual disturbances: blurred vision 
Calf cramps
Poor wound healing
Pruritus

Question 7

How is diabetes mellitus diagnosed?

Answer 7

(Based on WHO criteria)
(Symptomatic patients) fasting glucose greater than or equal to 7.0 mmol/l
random glucose greater than or equal to 11.1 mmol/l (or after 75g oral glucose tolerance test)

(Asymptomatic patients) HbA1c of greater than or equal to 6.5% (48 mmol/mol) is diagnostic of diabetes mellitus

Question 8

What are the additional tests for diabetes?

Answer 8

(Type 1) Anti-GAD antibodies
Anti-tyrosine phosphatase-related islet antigen (IA-2)
Islet cell surface antibody (ICSA; against ganglioside)
↓ C-peptide levels indicate an absolute insulin deficiency → type 1 diabetes

(Type 2) ↑ C-peptide levels may indicate insulin resistance and hyperinsulinemia → type 2 diabetes

(Urine analysis)Microalbuminuria → Early sign of nephropathy
Glucosuria + ketone bodies → diabetic ketoacidosis

Question 9

What is the treatment for type I diabetes?

Answer 9

(HbA1c) Monitoring every 3-6 months, target of HbA1c level of 48 mmol/mol (6.5%) or lower
(Blood glucose self-monitoring) at least 4 times a day
(Insulin) twice‑daily insulin detemir is the regime of choice. Once-daily insulin glargine or insulin detemir is an alternative + rapid‑acting insulin analogues injected before meals
(Metformin) metformin if the BMI >= 25 kg/m²

Question 10

What is the common initial treatment for type II diabetes?

Answer 10

(Lifestyle changes)
(HbA1c targets) Lifestyle 48 mmol/mol (6.5%)
Lifestyle + metformin 48 mmol/mol (6.5%)
Includes any drug which may cause hypoglycaemia (e.g. lifestyle + sulfonylurea) 53 mmol/mol (7.0%)

Question 11

What is the treatment for metformin-tolerant type II diabetics?

Answer 11

metformin offered if the HbA1c rises to 48 mmol/mol (6.5%) despite lifestyle interventions
HbA1c has risen to 58 mmol/mol (7.5%) then a second drug should be added (sulfonylurea, gliptin, pioglitazone, SGLT-2 inhibitor)
(HbA1c rise remains above 58 mmol/mol (7.5%) triple therapy: metformin + gliptin + sulfonylurea
→ metformin + pioglitazone + sulfonylurea
→ metformin + sulfonylurea + SGLT-2 inhibitor
→ metformin + pioglitazone + SGLT-2 inhibitor
or insulin (human NPH insulin (isophane, intermediate acting) taken at bed-time or twice daily)
(If triple therapy ineffective) metformin, a sulfonylurea and a glucagonlike peptide1

Question 12

What is the treatment for metformin-intolerant type II diabetics?

Answer 12

(if the HbA1c rises to 48 mmol/mol (6.5%) despite lifestyle interventions) sulfonylurea, gliptin, pioglitazone
(HbA1c has risen to 58 mmol/mol (7.5%)) → gliptin + pioglitazone; gliptin + sulfonylurea; pioglitazone + sulfonylurea
(HbA1c remains above 58 mmol/mol (7.5%) insulin therapy (human NPH insulin (isophane, intermediate acting) taken at bed-time or twice daily)

Question 13

What are the risk factor modifications in diabetes?

Answer 13

(Blood pressure) target is < 140/80 mmHg (or < 130/80 mmHg if end-organ damage is present)
ACE inhibitors are first-line
(Lipids) 10-year cardiovascular risk > 10% (using QRISK2) should be offered a statin (atorvastatin 20mg)
(Antiplatelets) Only offered in patients with existing cardiovascular disease