Diabetes type 2 in adults


− Diabetes is a metabolic disorder that leads to hyperglycaemia.
− Type 2 diabetes usually occurs in adults and accounts for 90% of diabetes cases worldwide.
− Type 2 diabetes can lead to acute complications, as well as chronic complications that result in serious organ damage (cardiovascular events; diabetic retinopathy, neuropathy, nephropathy).

Clinical features

− Few or no symptoms; symptoms of hyperglycaemia may be present: polyuria (frequent urination) and polydipsia (excessive thirst and drinking).
− In rare cases, patients may present with severe hyperglycaemia (impaired consciousness, coma or acute dehydration).

Diagnosis

− Look for diabetes in the event of:
• symptoms of hyperglycaemia;
• cardiovascular disorders: stroke, myocardial infarction, hypertension;
• peripheral neuropathies, foot ulcers, absence of tendon reflexes or peripheral pulse.

− Diagnosis is made on one of the following results1:

 

Fasting blood glucose (a)

Random blood glucose (b)

Glycated Hb (d)

Symptomatic patient

1 fasting blood glucose ≥ 7 mmol/litre
(or ≥ 126 mg/dl)

1 random blood glucose ≥ 11 mmol/litre
(or ≥ 200 mg/dl)

1 HbA1c ≥ 6.5%

Asymptomatic patient

 

2 fasting blood glucose ≥ 7 mmol/litre on 2 samples collected at 2 different times (c)

1 random glucose ≥ 11 mmol/litre
followed by 1 fasting blood glucose ≥ 7 mmol/litre

2 HbA1c ≥ 6.5% on 2 samples collected at 2 different times (c)

(a) Fasting blood glucose test: performed on patient that has fasted at least 8 hours.
(b) Random blood glucose test: performed at any moment of the day.
(c) For example, interval of at least one or more days.
(d) Glycated Hb (HbA1c) reflects average glycaemia over around 3 months.

Note: even in a symptomatic patient, it is preferable to perform a second blood glucose test to confirm the result.

Treatment

Glycaemic targets2

Fasting blood glucose < 8.3 mmol/litre (or < 150 mg/dl) or HbA1c between 7 and 7.5.
The closer blood glucose levels remain to these values, the more cardiovascular complications are prevented or delayed.
Depending on the context (healthcare provision) or patient profile (elderly patient, history of severe hypoglycaemia or long-standing poorly controlled diabetes), fasting blood glucose < 10 mmol/litre (or < 180 mg/dl) or HbA1c of around 8 are acceptable.
Blood glucose should not fall < 4.5 mmol/litre (or < 80 mg/dl) or HbA1c < 6.5.

Lifestyle and dietary advice1

− Avoid sugared foods and drinks (but no excessive restriction of carbohydrates). 
− High fibre intake; limit animal fats and alcohol.
− Physical activity.
− Weight control. If BMI ≥ 25, try to reduce weight by 5 to 10%.
− Stop smoking.

Pharmacological treatment

First-line treatment metformin PO2 .
The usual dose is 1 to 2 g daily. For information:
Week 1: 500 mg once daily in the morning at breakfast
Week 2: 500 mg 2 times daily (morning and evening) during meals
Increase in increments of 500 mg per week as long as the drug is well tolerated (max. 2 g daily, i.e. 1 g morning and evening)3.

If glycaemic control is not acheived, administer metformin in combination with a sulfonylurea.
Sulfonylurea doses are adjusted in increments to avoid the risk of hypoglycaemia, based of blood glucose results.
• In patients under 60, glibenclamide PO:
The usual dose is 5 mg 2 times daily. For information:
Week 1: 2.5 mg once daily in the morning at breakfast
Week 2: 5 mg once daily in the morning at breakfast
Increase in increments of 2.5 mg weekly until fasting blood glucose reaches target levels (max.15 mg daily).
• In patients over 60, gliclazide PO (immediate release tablet):
The usual dose is 40 to 80 mg 2 times daily. For information:
Weeks 1 and 2: 40 mg once daily in the morning at breakfast
Increase in increments of 40 mg every 2 weeks (weeks 3 and 4: 80 mg once daily in the morning at breakfast) until fasting blood glucose reaches target levels (max. 240 mg daily, i.e. 120 mg morning and evening).

If glycaemic control is not acheived with the combination of metformin + a sulfonylurea, continue metformin but replace the sulfonylurea with intermediate-acting insulin SC: start with 0.2 IU/kg at bedtime. The dose is adjusted after measuring fasting blood glucose in the morning. Once blood glucose levels have stabilized, test levels once weekly then after each consultation. Doses of 1 IU/kg/day or more may be necessary to reach glycaemic targets. If the necessary dose is over 0.5 IU/kg/day, administer in 2 injections daily.

Adjustment of intermediate-acting insulin dosage based on blood glucose levels

Morning blood glucose 

Action

< 4 mmol/litre
< 70 mg/dl

Treat hypoglycaemia (see Hypoglycémie, Chapter 1).
Reduce daily dose of insulin by 2 to 4 units.
Maintain new dose for 4 days.
Check blood glucose after 4 days, readjust dose if glycaemic target has not been not reached.
Check blood glucose again after 4 days and repeat the process until glycaemic target is reached.

≥ 4 and < 8.3 mmol/litre
≥ 70 and < 150 mg/dl

Do not change dose.

≥ 8.3 and < 11 mmol/litre
≥ 150 and < 200 mg/dl

Increase daily dose of insulin by 2 units.
Check blood glucose after 4 days, readjust dose if glycaemic target has not been not reached.
Check blood glucose again after 4 days and repeat the process until glycaemic target is reached.

≥ 11 and < 16,5 mmol/litre
≥ 200 and < 300 mg/dl

Increase daily dose of insulin by 4 units.
Check blood glucose after 4 days, readjust dose if glycaemic target has not been not reached.
Check blood glucose again after 4 days and repeat the process until glycaemic target is reached.

≥ 16.5 mmol/litre
≥ 300 mg/dl

Perform dipstick analysis for ketones.
Treat hyperosmolar hyperglycaemia or ketoacidosis if present.

Example for a man weighing 79 kg:
Start with 16 IU per day (79 kg x 0.2 IU).
On D4, blood glucose is 14.6 mmol/litre. Add 4 IU (daily dose of insulin is 20 IU). 
On D8, blood glucose is 10.4 mmol/litre. Add 2 IU (daily dose of insulin is 22 IU). 
On D12, blood glucose is 6.1 mmol/litre. Glycaemic target is reached. 

Surveillance and monitoring

Laboratory surveillance
− Patients on oral hypoglycemic agents: blood glucose test once a month to begin with, then during monitoring visits.
− Patients on insulin: fasting blood glucose test during the dose adjustment phase then, if possible, once weekly, once the insulin dose stabilised. 
− HbA1c if available: every 3 months, then every 6 months if well stabilised.
− Other necessary tests according to comorbidities and chronic complications.

Clinical monitoring
− Routine consultations: check blood pressure (should remain < 140/80 mmHg) and weight, examine feet. Consultations once a month for the first 6 months, then individualised frequency of consultations depending on the patient's characteristics (e.g. once every 6 months if the diabetes is well controlled).
− Annual check-up: check for cardiovascular and neurological complications, evaluate renal function (creatinine and proteinuria dipstick tests), examination of teeth and gums.
− Management of diabetes complications.

Patient education
− Lifestyle and dietary measures (diet, physical activity, etc.).
− Patients on sulfonylurea or insulin therapy: signs of hypoglycaemia/hyperglycaemia and management.
− Patients on insulin therapy: auto-administration (schedule, injection sites and techniques); storage of insulin; self-monitoring of blood glucose and adjustment of doses in patients using glucometers.
− Patients with sensory neuropathy or peripheral arterial disease: autoexamination of feet: prevention of foot lesions.



Footnotes
Ref Notes
1 These measures concern all patients regardless of medication prescribed. They can be sufficient alone to normalize blood glucose levels in certain patients.
2 If metformin is contraindicated or not tolerated, replace with a sulfonylurea.


References

  1. Partners in Health. Chronic care integration for endemic non-communicable diseases, Chapter 7, Table 7.1. PIH, Boston, 2013.
    https://www.pih.org/sites/default/files/2017-07/PIH_NCD_Handbook.pdf.pdf [Accessed 13 June 2018]

  2. American Diabetes AssociationGlycemic targetsDiabetes Care 2017 Jan; 40 (Supplement 1): S48-S56.
    https://doi.org/10.2337/dc17-S009 [Accessed 13 June 2018]

  3. Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press
    http://www.medicinescomplete.com> [Accessed 18 June 2018]