Achieving and Maintaining Glycaemic Control
Insulin therapy in type 2 diabetes
Treating to target in type 2 diabetes
Initiating insulin in primary care
First steps
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Get a background history including:
- symptoms of diabetes, if any
- symptoms of complications
- family history of diabetes
- other cardiovascular risk factors -
Physical examination should include:
- body mass index
- blood pressure
- feet -
Arrange tests including:
- HbA1c
- lipids
- serum creatinine
- urine microalbumin -
Provide an explanation for diabetes
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Provide lifestyle advice on nutrition, physical activity, smoking and alcohol (see Lifestyle Management section)
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Instruct on home blood glucose monitoring (see Self Management section)
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Start on an oral hypoglycaemic agent as appropriate (see below)
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Provide written literature on diabetes
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Provide a hand held diabetes record
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Arrange an early follow up appointment
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Enter patient details on practice diabetes register
Oral hypoglycaemic agents
Metformin
- The treatment of choice in the overweight (BMI>25)
- Reduces insulin resistance and increases hepatic glucose uptake
- Dose titration helps to minimise GI side effects
- Start with 500 mg bd 30 min after meals and increase gradually if necessary to a maximum of 1000 mg bd
- Should not be started in patients with severe cardiac, liver or renal impairment (creatinine >130umol/l)
Sulphonylureas
- Useful provided beta cell function is preserved
- Warn patient about possibility of hypoglycaemia, especially with the longer acting varieties
- Gliclazide dose is typically 80 mg once or twice daily taken before meals
Short acting insulin secretagogues: Repaglinide and Nateglinide:
- Rapid acting insulin secretagogues with possible advantage in avoidance of hypoglycaemia and control of post-prandial glucose
Acarbose
- Slows down glucose uptake from the gut
- Dose titration may help reduce GI side effects which are very common
Glitazones
- Can be used as monotherapy or combination therapy
- Very effective at lowering insulin resistance
- Require monitoring of LFT's during the first year until safety is assured
- Typical doses are rosiglitazone 4-8 mg daily and pioglitazone 15-45 mg daily
- Contraindicated in heart failure
- Contraindicated (in Europe) in combination with insulin
Stepwise approach
- Diabetes is a progressive disease which requires more and more intensive treatment to control the hyperglycaemia with time. Expect continuous need to increase doses of oral hypoglycaemic agents and to add other agents to address deterioration in glycaemic control with time due to the combined effects of insulin resistance and beta cell failure .
- The HbA1 level is normally a good guide to glycaemic control. The target level set by NICE is 6.5-7.5%, aiming for 6.5% in those patients at risk of vascular complications.
- If an initial three month trial of lifestyle changes does not result in target HbA1 level, then start an oral hypoglycaemic agent
- Convert to dual oral therapy if target HbA1 level is not met after a further 3-6 months. Possible combinations include metformin and a sulphonylurea, metformin and a glitazone (recommended in obese patients), or a sulphonylurea and a glitazone.
- When dual oral therapy is not sufficient to give target HbA1 levels, conversion to insulin should be considered (see below). Alternatively, although not yet recommened by NICE, triple oral therapy using metformin, a sulphonylurea and a glitazone is likely to be successful if the HbA1c is no greater than 8-8.5%. Triple oral therapy has been endorsed by the Association of British Clinical Diabetologists and by the International Diabetes Federation.
Insulin therapy in type 2 diabetes
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Insulin therapy is required in type 2 diabetes when HbA1 targets are not met despite maximum attention to diet and oral agents
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Use NPH insulin at night or long acting analogue at any time of day in people with good insulin secretory reserve. Titrate dose to achieve average fasting blood glucose level of <5.5 mmol/l (see Table below)
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Continue with oral hypoglycaemic drugs at this stage
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If HbA1 remains above target level, add pre-prandial short acting insulin (basal bolus regimen) in the majority of people. Alternatively, use pre-mixed insulin twice daily insulin. Contiue with metformin if given, but stop other oral agents at this stage
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Adjust therapy using self monitored results until insulin doses are adequate to reach post prandial blood glucose target of <9 mmol/l
Treating to target in type 2 diabetes
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Monitor HbA1c every 3 months if change in treatment, otherwise every 6 months as appropriate
Lifestyle Change |
Weight control Low sugar Low fat Low salt |
High fibre Alcohol moderation Regular exercise No smoking |
HbA1c target not met |
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Monotherapy |
Metformin or Glitazone or Insulin secretagogue Metformin preferred if overweight unless poorly tolerated or poor cardiac, hepatic or renal function |
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HbA1c target not met  |
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| Dual Therapy | Metformin + Glitazone if obese OR Metformin + Insulin secretagogue OR Glitazone + Insulin secretagogue |
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HbA1c target not met |
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| Triple Therapy | Metformin + Glitazone + Insulin secretagogue If osmotic symptoms present or HbA1c>8-8.5%, go straight from dual therapy to insulin |
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HbA1c target not met |
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| Insulin Therapy | Start 10 units basal insulin (NPH at bed time; long acting analogue at any time) Stop glitazone if taken Increase daily insulin dose by 2-8 units every week if average fasting blood glucose >5.5 mmol/l Regular contact with diabetes care professional to optimise dose titration |
|
HbA1c target not met |
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Add prandial insulin sequentially, starting with 4 units of short acting analogue before the biggest meal. Adjust dose to give 1-2 h post prandial blood glucose <9 mmol/l. OR Convert to twice daily premixed insulin for those reluctant to start basal bolus regimen Stop all oral agents except metformin |
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Initiating insulin in primary care
Training
Initial steps
Visit 1
Visit 2
Visit 3
Visit 4
Follow up
Types of insulin
Insulin regimens
Insulin adjustment
Other issues
Training
All those GP's and Practice Nurses who had completed the University of Warwick Certificate in Diabetes were given the opportunity to enrol on to the Insulin For Life Programme. This course is very much about team effort and some surgeries have also involved their district nurses.
They were invited to 2 half-day study afternoons to learn about insulin initiation. The study days are run and organised by the 2 senior Diabetes Specialist Nurses within Carmarthenshire NHS Trust.
Once the teams from each surgery have completed the study days they must then embark on highlighting those patients that require insulin therapy. These will be patients on maximum hypoglycaemic agents, but still with an HBA1c above 7.5%. Within the following 6 months they must initiate patients on to insulin therapy. They also need to keep a reflective practice diary.
When this has all been completed and signed off by their assigned Diabetes Specialist Nurse they will receive the Warwick University Certificate of advanced clinical practice.
The senior Diabetes Specialist Nurses have time available to support the various surgeries embarking upon this programme.
• Make decision if patient needs to start insulin treatment:
- HBA1c results
- Home blood glucose monitoring results
- Assess symptoms of hyperglycaemia (refer to hyperglycaemia section)
- Assess present treatment (refer to treatment section)
- Make decision upon these findings.
- Decide if the person needs to be referred to secondary care or not.
• If insulin initiation is to take place in Primary care then consider next steps :
- Agree within the team which insulin regime and what dosage would be appropriate for this patient.
- Ensure all staff involved are familiar with pen devices.
- Arrange date for patient to discuss decision with yourself and GP. Ask patient to bring blood glucose monitoring booklet and meter with them.
- Arrange date for Diabetes Specialist Nurse to visit if required.
Visit 1
-Discuss need for insulin therapy.
-Demonstrate pen device.
-Allow patient to give a dummy injection.
-Discuss insulin regime and timing of injection.
-Check patient's blood glucose monitoring technique.
-Inform patient of the need to inform DVLA and Insurance Company about commencing insulin therapy.
-Briefly discuss hypoglycaemia and its treatment.
-Organise Prescription.
-Arrange date to commence insulin.
-Remind patient to bring food with them if they will need to eat after giving their injection.
-Complete check-list
-Suggest patient brings a family member with them.
Remember to give patient:
-Demo pen to practise.
-Information leaflet regarding insulin type.
-Booklet on starting insulin
-Give prescription and ask patient to bring insulin, pen device and needles to next visit
-Answer any questions the patient and family may have
-Recap on how to use the pen device, and run through the step by step injection guide
-Observe patient giving their first injection
-Discuss timing of meals and healthy eating options (see nutrition in "Lifestyle Management" section)
-Discuss hypoglycaemia, signs and symptoms and treatment. This topic is discussed in detail in the patient section of the website and can be accessed for printing by clicking here
-Give advice regarding driving and hypoglycaemia
-Advise they may notice some change in their vision. If this happens it is advised not to drive until the vision settles down (which can take 4-6w)
-Ensure the patient knows how to safely dispose of sharps
Remember to give patient:
-Sharps box
-Identification card
-BD hypoglycaemia card
-Advise to buy lucozade and dextrose tablets to carry on them at all times.
-Answer any questions the patient and family may have
-Discuss interpretation of patient's home blood glucose levels
-Discuss insulin dose and how to make appropriate adjustment
-Discuss injection technique and the importance of rotating injection sites
-Discuss importance of regular meal patterns
-Exercise (see physical activity in the Living with Diabetes section) -Ensure patient has informed DVLA/Insurance Company
-Review blood monitoring
-Assess if insulin needs to be adjusted (see table below)
-Review patient's knowledge
-Discuss sick day rules
Remember to give: -
-BD leaflet on holidays abroad
-BD needle clipping device
-Weekly until patient confident about adjusting insulin dose
-Progress gradually to monthly -3monthly
-Reviewed then 3-6 monthly in diabetes clinic
-At each review you will need to assess patient's knowledge by asking a few simple questions
-HBA1c should be checked at 3 monthly intervals
Type |
Length of peak action |
Rapid Acting (analogue) Novorapid, Humulog |
2hrs |
Long acting (analogue) Lantus, Detemir |
24hrs |
Short acting (soluble) Actrapid, Humulog S |
4hrs |
Intermediate acting (isophane) Insulatard , Humulin I |
12hrs |
Insulin mixtures (biphasic) Mixtard 30/70, Humulin M3 |
4-12hrs |
Insulin mixtures (biphasic analogue) Novomix 30 , Humulog mix25 |
2-12hrs |
Once daily injection (refer to treatment to target section)
- Usually used in combination with oral hypoglycaemic agents
- Starting dose = 10units daily.
- Once a week, review the average fasting home monitored blood glucose over the previous three days. Provided there have been no episodes of hypoglycaemia accompanied by blood glucose <4 mmol/l, increase the insulin dose as shown below:
Mean FBG mmol/l |
Insulin dose increase units/day |
<5.5 |
0 |
5.5-6.7 |
0-2 |
6.8-7.8 |
2 |
7.9-10 |
4 |
>10 |
6-8 |
Basal-bolus regime ( refer to treatment to target section)
- This consists of a long acting analogue insulin, which is usually given just before going to bed, with added pre-meal doses of a rapid acting analogue insulin to be given during the day.
- Starting dose = 10 units at night of the long acting analogue and
- 4 units of the rapid acting analogue pre-meals
Twice daily mixture (refer to treatment to target section)
- This is an analogue mixture to be given twice daily, pre-breakfast and pre-evening meal.
- Starting dose = 12units am & 8units pm
If blood glucose levels are high/low first thing in the morning:
- Once daily -increase/decrease dose
- Twice daily -increase/decrease evening dose
- Basal bolus -increase/decrease basal insulin
If blood glucose levels are high/low during the day:
- Twice daily -increase/decrease morning insulin
- Basal bolus -increase/decrease preceeding insulin bolus dose
Refer to "Monitoring" section for advice on blood glucose monitoring
Do not make adjustments according to one off readings (high or low). Try to find the cause of abnormal blood glucose levels. Advise patient to monitor more frequently for a few days to assess the glycaemic control.
Injection technique -ensure they are following the correct guidelines. If able observe them giving an injection (give injection guidelines).
Lipohypertrophy -lumpy areas at the injection site. Repeated injections in the same area will cause a build up of insulin, which could account for erratic blood glucose levels.
Correct needle size - there are various needle sizes. If the needle is too long and the patient does not perform a lift of the skin prior to the injection then the patient could be injecting into the muscle. If this happens then it will affect the absorption of the insulin.
- 5-6mm for thin or muscular people.
- 8mm for those of average weight.
- 12mm for obese people.
absorption of insulin - pay particular attention if someone is exercising regularly, as absorption rate is increased if the muscle is being worked harder
- Fast absorption from the stomach
- Slower absorption from the thigh
Safe disposal of sharps -
- A sharps box for the house
- A BD needle-clipping device when travelling or going on holidays .
Referral Guidelines
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If the Practice does not yet participate in basal insulin initiation, refer to secondary care when oral therapy no longer achieves target HbA1c levels
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If not confident with initiation of prandial insulins, refer when basal insulin and oral drugs no longer achieve target HbA1c levels
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Refer when HbA1c >8% on maximal therapy when good glycaemic control is an appropriate target
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For further details see Referral Guidelines section