Type 2 Diabetes Mellitus

Treatment Plan

Investigations

Pathophysiology

Results from a combination of insulin resistance and less severe insulin deficiency

Decreased insulin secretion and increased insulin resistance

  • Associated with central obesity, hypertension, hypertriglyceraemia, decreased HDL, modest increase in pro-inflammatory markers
  • Insulin binds normally to its receptor on the surface of cells, as normal, thus insulin resistance occurs post receptor
  • Most patients show amyloid deposition in Islets in pancreas (co-secreted with insulin)

Diagnostic tests 1

  • Random plasma glucose > 11.1mmol/l
  • Fasting plasma glucose > 7mmol/l
  • For both tests one abnormal value is diagnostic in symptomatic individuals
  • Two abnormal values are required in asymptomatic values

Diagnostic tests (for borderline cases)

  • Oral glucose tolerance tests (OGTT)
  • Fasting >7mmol/l = diabetes diagnosis
  • 2hrs after glucose >11.1mmol/l = diabetes diagnosis

Can also detect impaired glucose tolerance (IGT) - a risk factor for future diabetes and cardiovascular disease

  • Fasting <7mmol/l
  • 2hrs after glucose 7.8 - 11 mmol/l

Haemoglobin A1c

  • Measures amount of glycated haemoglobin - thus tells us blood glucose concentrated
  • HbA1c> 6.5% normal (48mmol/mol) = diabetes diagnosis

Screen urine for Microalbuminuria

FBC, U&E, liver biochemistry, fasting blood sample for cholesterol and triglycerides

Raised blood pH to look for metabolic acidosis

MDT approach

Educate patient on disease and risks

Encourage regular physical activity and reduction in body weight in the obese

Good glycemic control with good diet -

  • Low in sugar
  • High in starchy carbohydrates
  • High in fibre
  • Low in fat

Treatment of hypertension with ACE inhibitors and hyperlipidaemia control

  • Orlistat may be given in obesity to reduce the absorption of fat from the diet
  • As a second line mechanism, oral metformin may be given
  • Reduces rate of gluconeogenesis in the liver
  • Increases cells sensitivity to insulin
  • Helps with weight issue and reduces CVS risk in diabetes
  • Side effects of anorexia, diarrhoea, nausea, abdominal pain, NOT HYPOGLYCAEMIA
  • Contraindicated in heart failure, liver disease or renal disease, since can induce lactic acidosis

If HbA1c > 53mmol/l 16 weeks later then add a sulfonylurea (e.g. oral gliclazide)

  • Promotes insulin secretion
  • These are ineffective in patients without functional cell mass
  • Avoided in pregnancy
  • Effect wears off as beta-cell mass declines
  • Side effects of hypoglycaemia, promote weight gain (avoid in overweight)
  • Used in care in those with liver disease and renal impairment
  • Safest drug in the elderly

If at 6 months the HbA1c > 57mmol/l consider adding insulin or a glitazone (to replace metformin or sulfonylurea)

Epidemiology

Causes

Signs

Complications

Diabetes is usually primary but may be secondary to other conditions such as:

  • Pancreatic pathology
  • Endocrine disease e.g. Acromegaly
  • Drug induced e.g. corticosteroids

Often overweight around the abdomen

More prevalent in South Asian, African and Caribbean ancestry

Usually older than 30 yrs

Middle Eastern and Hispanic Americans also more at risk

Common in all populations enjoying an affluent lifestyle

Risk factors

Obesity and poor exercise

Ethnicity

Increasing age

Environment

Family history - genetics

Symptoms

Polydipsia

Weight loss

Polyuria and nocturia

Ketosis - but less marked than T1DM

As a presenting feature

Staphylococcal skin infection

Retinopathy found during visit to optician

Polyneuropathy causing tingling and numbness in the feet

Erectile dysfunction

Arterial disease resulting in MI or peripheral gangrene

Breath MAY smell of ketones

Older patients may have retinopathy - DIAGNOSTIC

Evidence of weight loss and dehydration may be present

Acanthosis nigricans - blackish pigmentation at the nape of the neck and in the axillae

Microvascular

Macrovascular

Risk factor for atherosclerosis

Peripheral vascular disease - decreased perfusion due to atherosclerosis

Danger in the retina, glomerulus and nerve sheath

Diabetic retinopathy, nephropathy and neuropathy