Diabetes mellitus
Saturday, 19 November 2022
13:40
Types:
Type 1 Diabetes mellitus (T1DM)
o Cause -> insulin deficiency from autoimmune destruction of insulin-
secreting pancreatic B cells
o Onset -> presents in children/early adult life
o Patients require insulin and are prone to ketoacidosis and weight
loss
o ~90% associated with autoimmune disease (HLA DR3 +-DR4)
o Latent autoimmune diabetes of adults (LADA) with slower
progression to insulin dependence in later life
Type 2 Diabetes mellitus (T2DM)
o (non-insulin dependent DM)
o Cause -> reduced insulin secretion +- increased insulin resistance
o Associations -> obesity, lack of exercise, calorie and alcohol excess
o Typically progresses from a preliminary phase of impaired glucose
tolerance (IGT) or impaired fasting glucose (IFG)
o Maturity onset diabetes of the young (MODY) - rare autosomal
dominant form f T2DM affecting young people
Prediabetes
o Those expected to have diabetes within 2 years
o Fasting glucose of 6.1-6.9 or HbA1C 42-47
Impaired glucose tolerance (IGT):
Fasting plasma glucose <7mmol/L + OGTT (oral glucose tolerance) 2h
glucose >=7.8mmol/L but <11.1mmol/L
Offer an OGTT to rule out diabetes -> (7.8-11.1 mmol/L = not diabetic with
impaired glucose tolerance)
Impaired fasting glucose (IFG):
Fasting glucose >=6.1mmol/L but <7mmol/L
Causes:
Steroids: anti-HIV drugs
Pancreatic: Pancreatitis, surgery, trauma, pancreatic destruction
(haemochromatosis, cystic fibrosis), cancer
Cushing's disease
Acromegaly
Phaeochromocytoma
Hyperthyroidism
Pregnancy
Diagnosis:
Symptomatic:
o Symptoms of hyperglycaemia
Polyuria
Polydipsia
Unexplained weight loss
Visual blurring
Genital thrush
, Lethargy
Glucose testing:
Normal glycaemic Prediabet Diabetes mellitus
control es
Fasting Less than or equal 6.1- Greater than or equal
glucose to 6.0mmol/L 6.9mmol/L to 7.0mmol/L
HbA1C Less than or equal 42- Greater than or equal
to 41mmol/L 47mmol/L to 48mmol/L
Differentiating type 1 and type 2:
T1DM T2DM
Cause Autoimmune B-cell Insulin resistance/ B-cell
destruction dysfunction
Age Usually <20 >40 (usually)
Speed of Acute, hours/days Slower, weeks -> months
onset
Weight Recent weight loss Obese
Features Polydipsia Often
Polyuria asymptomatic
Ketosis
Ketonuria Common Rare
TYPE 1 DIABETES MELLITUS
Presentation:
Weight loss
Polyuria
Polydipsia
Diabetic ketoacidosis
o Abdominal pain
o Vomiting
o Reduced consciousness
Investigations:
Urine dip - glucose + ketones
Fasting glucose + normal glucose
HbA1C not recommended
C-peptide levels are usually low
Diabetes specific antibodies:
o Anti-GAD
o Islet cell antibodies
o Insulin autoantibodies (IAA)
Diagnostic criteria:
>IF SYMPTOMATIC
Fasting glucose >= 7mmol/L
, Random glucose >= 11.1 mmol/L
>Patients often have 1 or more of:
Ketosis
Rapid weight loss
Age of onset < 50 years
BMI < 25 kg/M2
Further testing (C-peptide, autoantibody titres) may be required if:
Atypical features
o Age >50
o BMI > 25
o Slow progression hyperglycaemia
Management:
>HbA1C
Monitor 3-6 months
Target = <48mmol/L
>Self-monitoring of blood glucose
Test 4 times/day
>Blood glucose targets
5-7 mmol/L on waking
4-7 mmol/L before meals
>Insulin
Multiple daily injection basal-bolus insulin regimes
o BD biphasic regimen - twice daily premixed insulin by pen (NovoMIX
30)
o QDS regimen - before meals ultra-fast insulin + bedtime long-acting
analogue
o Once-daily before-bed long-acting insulin
>Metformin
Consider adding if BMI >=25 kg/m2
TYPE 2 DIABETES MELLITUS
Diagnosis:
HbA1C >=48mmol/L
Fasting glucose >=7mmol/L
Management:
, Consider GLP-1 mimetics if not suitable for insulin
o Only continue f HbA1C drops by 11mmol/L and 3% weight loss in 6
months
>Risk factor modification:
Blood pressure
Clinic ABPM/
BP HBPM
Age < 140/90 135/85
80yrs
Age > 150/90 145/85
80yrs
Antiplatelets
o Only offer in CVD
Lipids
o If QRISK > 10%
o Primary prevention
QRISK >10%, CKD with eGFR < 60
Atorvastatin 20mg OD - 80mg OD
o Secondary prevention
IHD,CVD,PAD
Saturday, 19 November 2022
13:40
Types:
Type 1 Diabetes mellitus (T1DM)
o Cause -> insulin deficiency from autoimmune destruction of insulin-
secreting pancreatic B cells
o Onset -> presents in children/early adult life
o Patients require insulin and are prone to ketoacidosis and weight
loss
o ~90% associated with autoimmune disease (HLA DR3 +-DR4)
o Latent autoimmune diabetes of adults (LADA) with slower
progression to insulin dependence in later life
Type 2 Diabetes mellitus (T2DM)
o (non-insulin dependent DM)
o Cause -> reduced insulin secretion +- increased insulin resistance
o Associations -> obesity, lack of exercise, calorie and alcohol excess
o Typically progresses from a preliminary phase of impaired glucose
tolerance (IGT) or impaired fasting glucose (IFG)
o Maturity onset diabetes of the young (MODY) - rare autosomal
dominant form f T2DM affecting young people
Prediabetes
o Those expected to have diabetes within 2 years
o Fasting glucose of 6.1-6.9 or HbA1C 42-47
Impaired glucose tolerance (IGT):
Fasting plasma glucose <7mmol/L + OGTT (oral glucose tolerance) 2h
glucose >=7.8mmol/L but <11.1mmol/L
Offer an OGTT to rule out diabetes -> (7.8-11.1 mmol/L = not diabetic with
impaired glucose tolerance)
Impaired fasting glucose (IFG):
Fasting glucose >=6.1mmol/L but <7mmol/L
Causes:
Steroids: anti-HIV drugs
Pancreatic: Pancreatitis, surgery, trauma, pancreatic destruction
(haemochromatosis, cystic fibrosis), cancer
Cushing's disease
Acromegaly
Phaeochromocytoma
Hyperthyroidism
Pregnancy
Diagnosis:
Symptomatic:
o Symptoms of hyperglycaemia
Polyuria
Polydipsia
Unexplained weight loss
Visual blurring
Genital thrush
, Lethargy
Glucose testing:
Normal glycaemic Prediabet Diabetes mellitus
control es
Fasting Less than or equal 6.1- Greater than or equal
glucose to 6.0mmol/L 6.9mmol/L to 7.0mmol/L
HbA1C Less than or equal 42- Greater than or equal
to 41mmol/L 47mmol/L to 48mmol/L
Differentiating type 1 and type 2:
T1DM T2DM
Cause Autoimmune B-cell Insulin resistance/ B-cell
destruction dysfunction
Age Usually <20 >40 (usually)
Speed of Acute, hours/days Slower, weeks -> months
onset
Weight Recent weight loss Obese
Features Polydipsia Often
Polyuria asymptomatic
Ketosis
Ketonuria Common Rare
TYPE 1 DIABETES MELLITUS
Presentation:
Weight loss
Polyuria
Polydipsia
Diabetic ketoacidosis
o Abdominal pain
o Vomiting
o Reduced consciousness
Investigations:
Urine dip - glucose + ketones
Fasting glucose + normal glucose
HbA1C not recommended
C-peptide levels are usually low
Diabetes specific antibodies:
o Anti-GAD
o Islet cell antibodies
o Insulin autoantibodies (IAA)
Diagnostic criteria:
>IF SYMPTOMATIC
Fasting glucose >= 7mmol/L
, Random glucose >= 11.1 mmol/L
>Patients often have 1 or more of:
Ketosis
Rapid weight loss
Age of onset < 50 years
BMI < 25 kg/M2
Further testing (C-peptide, autoantibody titres) may be required if:
Atypical features
o Age >50
o BMI > 25
o Slow progression hyperglycaemia
Management:
>HbA1C
Monitor 3-6 months
Target = <48mmol/L
>Self-monitoring of blood glucose
Test 4 times/day
>Blood glucose targets
5-7 mmol/L on waking
4-7 mmol/L before meals
>Insulin
Multiple daily injection basal-bolus insulin regimes
o BD biphasic regimen - twice daily premixed insulin by pen (NovoMIX
30)
o QDS regimen - before meals ultra-fast insulin + bedtime long-acting
analogue
o Once-daily before-bed long-acting insulin
>Metformin
Consider adding if BMI >=25 kg/m2
TYPE 2 DIABETES MELLITUS
Diagnosis:
HbA1C >=48mmol/L
Fasting glucose >=7mmol/L
Management:
, Consider GLP-1 mimetics if not suitable for insulin
o Only continue f HbA1C drops by 11mmol/L and 3% weight loss in 6
months
>Risk factor modification:
Blood pressure
Clinic ABPM/
BP HBPM
Age < 140/90 135/85
80yrs
Age > 150/90 145/85
80yrs
Antiplatelets
o Only offer in CVD
Lipids
o If QRISK > 10%
o Primary prevention
QRISK >10%, CKD with eGFR < 60
Atorvastatin 20mg OD - 80mg OD
o Secondary prevention
IHD,CVD,PAD
