If you are on MDI or an insulin pump, there are a number of steps to calculating how much insulin to give in response to your blood glucose measurement.
- Count or estimate the carbohydrate content in the food you are about to eat (if you are testing pre-meal).
- Calculate your meal bolus according to your insulin to carbohydrate ratio at that time of day.
- If your blood glucose measurement is above target, calculate your correction bolus, according to your insulin sensitivity at that time of day and whether or not any insulin is still active from your last bolus.
- Adjust for expected activity if you will be exercising within 2 hours after your bolus.
- Finally – eat and enjoy!
These steps can become second nature and perhaps we don’t even realise we are making so many mental calculations. A smart meter is a custom-built calculator to take away steps 2, 3 and 4. They make a calculation of how much insulin should be taken to bolus for food or correct a high blood glucose. Smart meters can help you avoid under or over dosing, stacking correction doses, and guestimating!
In the 2016 document “Standards of care for management of adults with type 1 diabetes“, the Association of British Clinical Diabetologists (ABCD) said:
“All patients with (type 1 diabetes) who are carbohydrate counting should be offered a bolus calculator to ease the burden of calculating insulin at mealtimes.”
Increased standards for blood glucose meters
In 2013, the International Organisation for Standardization published new quality standards for blood glucose meters in order to improve accuracy and consistency of results. A transition period was allowed, and all meters are expect to meet the new standard, ISO 15197, by now (May 2016).
ISO 15197 has 4 significant improvements on the previous standard (published in 2003).
- Increased accuracy for glucose meter systems, in particular for glucose values greater than 4.2 mmol/l
- Manufacturers of glucose meter systems must ensure their technology enables accuracy to improve from +-20% to +-15%
- The new version accounts for 99% of results, as opposed to 95% for the previous one
- For the first time, the standard provides formal acceptance criteria for accuracy as regards testing by patients and assessment of interferents (including hematocrit).
Even with the new standard for accuracy, there is an allowance for variation within what is deemed ‘accurate’. For example, your meter might show a reading of 6 mmols/L and still be ‘accurate’ enough to meet the new standards if your actual glucose level is anywhere between 5.1 mmols/L and 7 mmols/L. Diabetes.co.uk has a good reference table (second table on the page) here.
Regarding accuracy, the Diabetes Technology Society examined 18 popular BG testing systems available in the USA and found some very interesting results. Scroll down the page to see tables of their findings, published in 2015.
Note from MHRA: as of June 2017, test strips and solutions that are designed to be used with Blood Glucose Meters that are not compliant with ISO 15197:2013 will be considered to be a breach of the Medical Devices Regulations 2002.
MHRA advises users who currently have non-compliant meters that they should contact their healthcare professional to ensure that their meter is upgraded to one that is compliant.
ie, if you use an old meter, you won’t be able to get strips for it after June 2017. Time to upgrade!
Access to sufficient test strips / choice of brand
Has your GP changed the quantity or type of blood glucose test strips that you get on prescription – without asking you? If so, you’re not alone.
Across the UK, Clinical Commissioning Groups (CCGs) (in England) and Local Health Boards (in Scotland & Wales) are attempting to reduce the cost of diabetes care by limiting the number of blood glucose test strips available on prescription. Some authorities are requiring people with diabetes to use a particular blood glucose meter so they can buy strips in bulk at lower prices.
Saving money within the NHS should be encouraged, provided that the changes needed are consistent with National Institute for Clinical Excellence (NICE) guidelines and clinical evidence. NICE NG17 (for adults with type 1 diabetes) and NG18 (for children and young people with diabetes) support the need for blood glucose monitors that are most suitable for the individual patient.
NG17 (for adults with type 1 diabetes) says:
1.6.17 When choosing blood glucose meters:
Take the needs of the adult with type 1 diabetes into account.
Ensure that meters meet current ISO standards.
and NG18 says:
1.2.60 Offer children and young people with type 1 diabetes and their family members or carers (as appropriate) a choice of equipment for monitoring capillary blood glucose, so they can optimise their blood glucose in response to adjustment of insulin, diet and exercise.
Yet in some cases, individuals’ needs and preferences have not been taken into account. This tendency to discount patients as stakeholders needs to be addressed in order to maintain and improve the quality of diabetes care in the UK.
Patient Choice in Blood Glucose Testing
In July 2012, the Department of Health published a consultation document called ‘Liberating the NHS: No decision about me, without me‘, which has been endorsed by the Secretary of State for Health. As the title suggests, healthcare providers need to engage in dialogue with patients regarding treatments to meet individual needs. On the other side of the coin, we as patients need to engage in a long-term partnership with respect to our health. You have a right to feel satisfied that you have had adequate consultation and reached an agreement with your healthcare provider, rather than being told what to do.
For pictures and descriptions of all blood glucose meters currently available in the UK, see pages 4 to 9 of the Diabetes UK Meds & Kits guide 2015.
Obtaining Adequate Glucose Testing Strips
It has often been said that 99% of diabetes care is self-care: many people with type 1 diabetes spend less than 24 hours in the company of diabetes care professionals in an average year. Patients’ ability to self-manage diabetes depends on access to appropriate resources, including both drugs and blood glucose monitoring.
NICE NG17 and NG18 (published in August 2015) sets out advice for commissioners and clinical teams on how many test strips should be used (and therefore prescribed by your GP):
1.6.10 Support adults with type 1 diabetes to test at least 4 times a day, and up to 10 times a day if any of the following apply…
(the list of circumstances that may demand more than four tests a day include illness, pregnancy, sport, and experiencing more hypos.)
1.2.59 Enable additional blood glucose testing (more than 10 times a day) for adults with type 1 diabetes if this is necessary because of the person’s lifestyle (for example, driving for a long period of time, undertaking high‑risk activity or occupation, travel) or if the person has impaired awareness of hypoglycaemia.
1.2.58 Advise children and young people with type 1 diabetes and their family members or carers (as appropriate) to routinely perform at least 5 capillary blood glucose tests per day.
1.2.59 Advise children and young people with type 1 diabetes and their family members or carers (as appropriate) that more frequent testing is often needed (for example with physical activity and during intercurrent illness), and ensure they have enough test strips for this.
If your GP does not give you adequate test strips on the grounds of cost, this simple statement may be all you need to persuade them: ‘If you think test strips are expensive, wait until you see how much it costs when I don’t test.’
If that argument doesn’t work, you could try the following steps in order:
- Discuss the matter with your GP. Even though it might seem obvious, say you have type 1 diabetes and have different needs from someone with type 2 diabetes.
- Ask your GP practice manager why they are not prescribing in line with NICE clinical guidance.
- Print this article, and this letter, and this blog post by Professor Peter Hindmarsh, and discuss them with your GP.
- Ask your diabetes consultant or diabetes specialist nurse to write to the GP to explain your individual clinical needs with regard to blood glucose testing.
- Raise the matter with your CCG/Local Health Board. Your GP will be able to give you the relevant contact information. In many parts of the country, local policies do not distinguish between type 1 and type 2 diabetes.
- Contact your local MP and ask them to help you resolve the situation.
If you would like support in following these steps, consider contacting a patient advocacy organisation. INPUT, JDRF and Diabetes UK are all taking an active interest in access to blood glucose testing and may be able to assist you.
Driving and Blood Glucose Testing
In addition to the long-standing minimum clinical requirements, since January 2012 the DVLA has made it mandatory for all people who use insulin and hold a driving licence to test blood glucose levels before driving and every 2 hours whilst driving. The current DVLA driving licence application form states:
“You MUST sign the declaration that you will test before and every two hours when you drive. [This is to let the DVLA know that you understand that you have to test while driving.] This is a legal requirement and a licence will not be issued if this declaration is not signed.”
People who use insulin must have access to an appropriate number of blood glucose test strips to be safe on the road. If your GP has reduced your test strip prescription so that you don’t have enough strips to comply with the DVLA rules, it is very important to push back! Your life and others’ safety may depend on it.
With thanks to Paul Coker for his contribution to the above.
June 2014 – Blog post by Professor Peter Hindmarsh, Paediatric Endocrinologist at University College Hospital in London
In addition to blood glucose monitoring and CGM systems described on this site, alternative approaches are being researched and developed but most are not yet available. These include:
The HSA-01 Hypoglycaemia Low Blood Sugar Alarm (use a search engine as there are a number of suppliers, including Amazon.co.uk) and other cold-sweat detecting devices (please let us know names of others and tell us if you use one!).
Not yet available
A number of technologies that do not require the skin to be punctured are being investigated, for both single-point testing and continuous monitoring. These include infrared, ultrasound and di electric spectroscopy.
Examples include these products, which are not yet available to purchase:
HypoMon – “A safer night’s sleep” for people aged up to 25. Launched then recalled. Website no longer available.
C8 Medisensors – a completely non-invasive monitor (website no longer available)…
GlucoTrack – uses ultrasonic, electromagnetic and thermal technologies via an ear-clip