Driving and hypoglycaemia – what are doctors being advised to do?

Driving and Diabetes

Driving and the EU law
News release: EU changes night-time hypos driving rules for people with diabetes
Driving and hypoglycaemia – what are doctors being advised to do?
Test Strips – Department Of Health Warning For Doctors And Pharmacists
Vehicles You Can Drive
Medical Assessment Forms
Insulin and Driving Taxis
Hypoglycaemia and Driving
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Driving and Visual Field Loss

Living with Diabetes


Driving and hypoglycaemia – what are doctors being advised to do?

The Association of British Clinical Diabetologists [ABCD] has recognised that the EU Directive on standards of driving in diabetes will have a significant impact not only on drivers with diabetes but also on the doctors who complete medical reports for the DVLA. The ABCD has clarified their response to the Directive and this basically advises doctors on their actions with their patients on the most important change – hypoglycaemia. [Practical Diabetes Vol. 29 No1] It seems sensible that people with diabetes know what advice their doctors are receiving, so below are the key points in the ABCD recommendations to doctors.

Just a reminder, the changes are:

  • If a Group 1 driver [car/motorcycle] has had two or more hypos requiring assistance from another person, day or night, in the previous 12 months, they must inform the DVLA and be advised not to drive.
  • If a Group 2 driver [bus/lorry] has one or more hypos in the previous 12 months, they must inform the DVLA and be advised not to drive.

What is a reportable hypo?
The requirement of assistance would include:

  • admission to Accident and Emergency,
  • treatment by paramedics,
  • treatment by a partner/friend with glucagon or glucose because the person with diabetes cannot do it themselves.

It does NOT include another person offering or giving assistance when the person is aware they are hypo and able to take action independently.

The ABCD is therefore advising hospital doctors to take great care to elicit an exact history of each hypo and chart it carefully in the records. It advises primary care teams to consider referral to specialist teams patients who have suffered one severe hypo requiring assistance because a second one could lead to loss of driving licence and loss of job.

What if people do not report their hypos?
While people may not report their hypos to their doctor, reports of hypos may be sent from the ambulance team or A & E to the patient’s GP, In this case, the ABCD advise that it would be ‘sensible to see the patient and inquire about the frequency and severity of hypoglycaemia’. If there have been two severe hypos requiring assistance from another person in the previous 12 months, the doctor MUST inform the patient that they need to notify the DVLA and advise the patient not to drive. The same applies to a Group 2 driver who has had one severe hypo.

What about unconfirmed night hypos?
Doctors may suspect that severe night hypos are happening to people who live on their own but these are not witnessed, because the person lives alone! This would not necessarily be an episode that should be reported, although the doctor may advise the patient to notify the DVLA. Silly though this sounds, people who live on their own and have severe night hypos, may be advantaged as far as reporting to the DVLA is concerned, although of course, not for their own health and wellbeing. If hypo unawareness is suspected, then it is advisable to refer the patient to specialist care.

What about hypo unawareness?
The ABCD suggest that for a Group 1 licence, where a patient’s home monitoring results show blood glucose levels of below 3mmol/L but reports no symptoms, this should be classed as hypoglycaemia unawareness. If hypoglycaemia below 3mmol/L without any awareness is typical of a patient’s hypos, then this may be classed as completely unaware and the patient should report this to the DVLA and be advised not to drive. When blood glucose levels are below 3 and there are no symptoms, cognitive dysfunction during the hypoglycaemia is likely to be present and  there is a risk of severe hypos. People with these types of hypos should be referred to specialist care for a review of their regime. 
Group 2 drivers have to have complete awareness, so any degree of unawareness results in the licence being revoked.

What are a doctor’s responsibilities if a patient continues to drive when they are not fit to do so?
The ABCD says that any doctor who is aware that a patient is not fit to drive, should advise the patient not to do so and to inform the DVLA. If the patient does not notify the DVLA or refuses to do so, under General Medical Council guidelines the doctor is allowed to notify the DVLA. However, it is advised that it is good practice to confirm the conversation in writing to the patient and also inform the patient that their insurance is no longer valid. 

What about people with Type 2 diabetes?
If Type 2 diabetes is treated with metformin, then this does not cause hypos. However, if sulphonylureas are added to the treatment, then they can cause hyoglycaemia? The ABCD say that if everyone treated with sulphonylureas were to be encouraged to test, this would hugely increase the cost of blood monitoring. [IDDT would question whether this is a good enough reason to not test?] It is stated that the greatest risk of hypos on sulphonylureas is in the first 3 months of treatment so ‘it would seem sensible to maintain current practice and only encourage extra testing in peole who are starting treatment, experiencing hypoglycaemia or with reduced awareness’. They also note that the highest risk of hypos in people with Type 2 diabetes prior to starting treatment with insulin is late afternoon.
A Group 2 driver on a sulphonylurea or glinide is required by law o test blood glucose levels at least twice daily and at times relevant to driving.

ABCD recommendations for safe blood glucose levels for driving

  • In a person with good hypo awareness, normal blood glucose levels are adequate but ABCD recommend testing before driving and at no longer than 2 hourly intervals while driving.
  • In a person with impaired awareness, ABCD recommend not driving without eating if blood glucose is under 7mmol/L although 5mmol/L is probably safe for a drive of under 10 minutes.