Diabetes Type 2
Testing blood glucose - monitoring diabetes
There are two sorts of blood glucose tests for people with diabetes. The HbA1c test which is done by a health professional and the 'finger-prick test' which you can do for yourself.
The HbA1c or glycated haemoglobin test is usually done once a year by the GP or specialist nurse as part of the annual check-up for people with type 2 diabetes (see 'Care and treatment for type 2 diabetes'). The test measures the amount of glucose that the body's red blood cells are carrying and indicates how blood glucose levels have been over the previous 2 or 3 months. If the result is high the test can be repeated in a few months after changes in diet or treatment.
Philip says that it is impossible to fool the HbA1c test.
Philip says that it is impossible to fool the HbA1c test.
So you know it's you have got, if you go every 12 months of course it means that you can do what you like for 9 months and then the other 3 months you have got to be careful, but you don't do that, because it is really about 12 weeks that they can look back on when they look back at the HbA1c. But if you're sensible you wouldn't try to - well you've got to look after yourself.
The finger-prick test gives an instant reading or snapshot of the glucose level in the blood at that moment which indicates whether your diabetes is under control. Regular testing had made many people we talked to more aware of foods they needed to limit or avoid altogether, and that exercise could help to reduce blood glucose levels.
Alex prefers to know what is happening to him and keep his diabetes under control and checks his...
Alex prefers to know what is happening to him and keep his diabetes under control and checks his...
Do you feel it's better this way that you actually can see what your blood sugar level?
Yeah.
Compared to how it was?
There's been a couple of occasions like yeah... It wasn't totally under control I can relate back to Boxing Day when I was at my daughter's house for the Boxing Day dinner, and that was [I] just probably over-indulged in the wrong things and I don't mean alcohol, I mean sweets and desserts etcetera. And it shot off the scale, it was away back up at high twenties just for one meal, but again it dropped back down within 24 hours again. So you learn then in the early stages that doing the wrong thing can affect it, which long-term will have an effect. So I prefer not to do that now, and try and keep it in check.
Many people with diabetes feel that they are bound to have better control of their blood sugar if they can monitor it themselves on a regular basis. But several large studies have failed to confirm this, and found that regular monitoring by people who are not taking insulin often increases anxiety about normal ups and downs in blood glucose levels without improving long-term control. A large part of the NHS annual spend on diabetes is taken up by the inappropriate use of blood testing strips, so in many parts of the UK there are local guidelines aimed at restricting their availability to appropriate levels for each stage of diabetes.
Blood glucose targets
Everyone with diabetes is advised to try to keep their blood glucose levels steady and within the recommended range. For most people with diabetes this is below 48mmol/mol (6.5 mmol/l*) (NICE guidelines for type 2 diabestes 2016). The 2016 NICE Type 2 diabetes guidelines do not contain recommendations for fasting and postprandial (before and after meals) blood glucose targets. However, Diabetes UK Council of Healthcare Professionals (CHP) has advised that the general targets recommended by NICE in the Type 2 diabetes 2008 guidelines be maintained as a guide.
The NICE – National Institute for Health Care Excellence guidelines for type 2 diabetes (2008) recommends that people with type 2 diabetes should aim for
• 4–7mmol/l* before meals (20-53 mmol/mol)
• less than 8.5mmol/l two hours after meals (69 mmol/mol):
It is important that individual blood glucose levels should be agreed between the person and their diabetes team. Normal blood glucose levels e.g. for someone without diabetes are 3.5 -5.5mmol/l before meals (15-37 mmol/mol) and under 8mmol/l (64 mmol/mol) 2 hours after meals.
*millimoles per litre: a measurement of the concentration of a substance in a given amount of liquid
Testing blood glucose is particularly important when you are feeling unwell for any reason or if blood glucose levels are unstable. If blood glucose levels dip too low, usually below 4 mmol/l, that is hypoglycaemia (Diabetes UK 2016). Too much glucose in the bloodstream is called hyperglycaemia (hyper). Both hypos and hypers can, if left untreated, lead to coma (see 'Managing hypos').
Balvinder explains why he only tests his blood sugar once every two weeks even though he has had...
Balvinder explains why he only tests his blood sugar once every two weeks even though he has had...
So have you ever had what they call a hypo, hypoglycaemia, when your blood sugar drops a lot? Have you ever had something like that?
Only once has it gone down to 2. That's it. It became 2 just once.
So then what symptoms did you have, how did it feel?
Like shaking. And I got very sweaty. And I couldn't stand up. So then I knew that it's very low. So then, you know milk, I put 2 or 3 spoonfuls of sugar so then I drank that. And after 5 minutes, I was okay. So, if that ever happens to me, I know that my sugar must be low. Sometimes I test it too, when it's low then I do test it, sometimes 3 or 4.
And so how often do you test your sugar normally?
I test it after every 2 weeks.
You don't test everyday?
No. Sometimes, it happens, sometimes, I do it after 3 or 4 days, otherwise every 2 weeks I definitely do it.
And what has your doctor advised you?
The doctor says that, 'Everyday you should test your sugar'. But I don't do that. He does it, he's also given me a book to write in. In the morning, before eating you should test your sugar. Then after food, after two hours, two hours, you have to check again [laughs]. It's too much for me. So I stopped it. I just test it myself sometimes, test myself. So when I test myself, nowadays it's usually 6 or 7. Roughly till about 9. It's never higher than that.
So the doctor asked you to test everyday, why don't you do it everyday?
Huh…Lazy. I am too lazy.
Does it cause discomfort to test yourself, is that why?
No, it's not that it causes discomfort, just like that, you know. What's the discomfort, it's just a machine, it doesn't take any time to test. You stick the needle in, and you just check it. That's it. Easy, it's easy to check you know. So just that, I'm lazy.
No but if you imagine that a doctor might listen to this recording, and the doctor is trying to understand why you don't test your blood, so what would you say to them?
The doctor will say to me, 'Why have you come here for?'. That's what the doctor will say to me. Doctors do say that, if sometime you don't check your blood, 'Why have you come here for?'.
So what would you say?
Huh. What is to say in that case? I'd just say, 'Can't help it'.
So if the doctor did really want you to test your sugar everyday, then what would need to happen that you start doing it?
If he said to me, 'If you don't test your blood everyday, then you don't come here anymore. I'll take your name off the list'. Then I'll have to do it. Then I'll have to do it.
For those who checked their blood glucose levels regularly - the 'finger prick' test - few had any difficulty with the procedure itself. Most had been given or had bought their own blood glucose meter which read their glucose levels automatically.
Pamela found using a blood glucose monitor was simple to learn and testing was generally quick...
Pamela found using a blood glucose monitor was simple to learn and testing was generally quick...
But I think the cylinders for the little tabs are probably not cheap. Well, I know they're not because I've bought some. But I think it's my way of, that's my way of keeping my sugars down, my sugar levels down, is to do it every day. I mean maybe it will come a time when I don't feel I have to. But it's working at the moment and that's okay. And I don't mind the needle, I don't mind the pinprick every morning, you know. That's fine.
Do you use a different finger every time?
Yes. And, but even so they do start to get (looking at fingers), because I don't, I mean I don't know what people, I've not really examined what people do who are on insulin and have to check their bloods four times a day. Presumably there's, they use different parts of their bodies or something, I don't know. But, no, that, that seems to work for me at the moment.
Andy has chronic pain as well as diabetes so found blood testing painful at first.
Andy has chronic pain as well as diabetes so found blood testing painful at first.
So how do you manage that now?
Well I don't have to do it so often now, I only do it now when I feel a bit, something doesn't feel right and I have to check what my blood is.
Right. And did you, did they teach you how to do that?
Oh yes. The diabetic nurse at the, when I first saw her, the first time I saw her a few days after I was diagnosed' She said, 'Oh I'll give you a machine and you test your blood and this is what you put the sharp thing in here, and you put it on there and you press this button and it stabs you.' I mean they're all very matter of fact. 'You know, you have a go'. And it hurt [laughs].
You see, one of the problems with chronic pain, is that little pains become big pains. People don't always understand that. So the little tiny scratch is actually a very sharp pain for me. Because my brain can focus on that compared to the pain in my back. And so it does. It's just one of the problems you have if you're a sufferer of chronic pain.
After the initial period of adjustment, some people on oral medication such as metformin chose to carry on testing themselves daily because they felt it helped keep them on the right track and helped them understand the relationship between food, exercise and blood glucose levels. There are no firm rules about whether those taking anti-diabetes tablets should or should not measure their blood glucose regularly; if you are in any doubt about what you should be doing ask your GP. However, people on insulin should test their blood glucose every day, ideally before each injection so that they know how much insulin they need to keep their glucose level stable.
Philip keeps track of his blood glucose readings by putting them on a spreadsheet.
Philip keeps track of his blood glucose readings by putting them on a spreadsheet.
So do you update it every time you take a reading?
Yes, oh, yes. It's an ongoing reading. It's only about six weeks now that I've been actually doing it like that. Because my testing kit actually has a memory on it and we could, if they wanted to, I could take that in to the clinic and they could actually print a readout of all my readings over the last six months. But they don't.
When Tina changed to a different type of insulin she tested her blood glucose ten times daily to...
When Tina changed to a different type of insulin she tested her blood glucose ten times daily to...
So how often do you do your blood sugars?
Now I can do them twice a day, and that's fine. But when I had to do them every before I ate, after I ate, four times you know I mean eight times a day, and then I'd usually do it before I went to bed as well. And first thing in the morning, so that's about ten times a day. But my fingers were like pin cushions [laughs]. But I had to do that because you have to be very you have to have very tight control on your sugar levels and get it in with the insulin that you're taking. So.
But that's made it harder for you?
It did in the beginning. Yes, it did. I mean that's quite a struggle to do that because I have to take it to work as well, so it's, it was quite a struggle, but it was worth it I think because my sugar levels have come down more.
And do you feel better in yourself?
I do feel better yes. I do feel better. I used to get really, really tired. I used to be asleep in the evening on the sofa, just fall asleep just watching TV, which I don't do now. I never do that now. But I wasn't aware at the time that that was what the problem was. I didn't, I just thought it was probably just age-related [laughs]. I don't know. I didn't know, I was just tired, I didn't put it down to being diabetic but yeah.
Not everyone wanted to test their blood glucose regularly; some people on oral medication had been advised not to check their levels in case they became over-anxious. The cost of test strips also put some people off routine testing.
Raj still checks his levels and records them for his GP because he may need more medication.
Raj still checks his levels and records them for his GP because he may need more medication.
I do. Every couple of days I check my sugar level and make sure that's right. As I got all the instruments and everything provided by my GP. And I check at home and everything's fine and it's all controlled now.
But you mentioned before that they're going to change the treatment?
They're just going to add another tablet, you know, that's what they're saying. And most probably I'll, they said to me, I have to go tomorrow to see my GP, and they are going to decide, you know, what sort of tablets they're going to add it on, just to make sure. Because the thing, what they want, they want my sugar level to be below 7. Which is, at the moment sometimes it's 7 and sometimes can go a bit higher, which, they're not happy with that. So that's what they going, they're trying to do, just to make sure it's below 7. Yes, there is, sometimes there is below 7. But they want it all the time to be controlled. And so that's why they're going to put me on the medicine.
And do you, do you note it down when you take your blood sugar reading?
I do. Well, when you're, it all started when I found around being diabetic. About the first six months I used to check my blood sugar every day and I used to write it down and everything. So just to make sure when I go back to see my GP to show them the results and how everything, how everything is working out. So they can see how was my blood sugar and how they can decide, you know, how, what sort of medicines I'm going to have it, that sort of things.
And now it's not every day?
No, it's not every day. Every two or three days, something like that, you know. When I, if I feel can, I should check it, I'll check it, you know. Because I know myself, you know, if it's going to be right or not, because from your own body you know whether it's going to be right or not. If you feel it's going to be a bit high, then most probably I'll check it, you know, or if it's going to be a bit low. But when it's right, you know, you feel in yourself everything is fine, you don't bother with that.
Duncan prefers not to check his glucose levels every day. The strips are too expensive and also...
Duncan prefers not to check his glucose levels every day. The strips are too expensive and also...
I mean I didn't see why I mean I wasn't prepared to keep spending money for something ' and I mean I was, I just tested myself every morning and I mean for weeks, I was just on, pretty much exactly the same every morning. And I thought well if the nurse and the doctor say I don't need to do it, I'm not going to keep spending '30 every couple of weeks just to do this. So in a way, I would be' I've still got the meter, I suppose I ought to kind of get another drum of strips, calibrate them up and just occasionally test myself just to be on the safe side. I've got a blood pressure monitor that I use occasionally just to check, but again that usually' Always seems to come up okay.
Once they had got their medication right, some people stopped testing blood glucose as regularly as before. Several people admitted that they hardly ever tested their blood glucose levels and increased or lowered their insulin by physical signs such as tingling in the lips even though they knew doctors don't recommend this.
Last reviewed March 2016.
Last updated March 2016.
Copyright © 2024 University of Oxford. All rights reserved.