Testing blood glucose: monitoring type 2 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.

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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…

Age at interview 54

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Age at diagnosis 51

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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. It is important that individual blood glucose levels should be agreed between the person and their diabetes team.

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, 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…

Age at interview 69

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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…

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Age at diagnosis 50

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Andy has chronic pain as well as diabetes so found blood testing painful at first.

Age at interview 52

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Age at diagnosis 52

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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.

Age at interview 68

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Philip checks his blood to avoid possible problems from a change of routine.

Age at interview 81

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When Tina changed to a different type of insulin she tested her blood glucose ten times daily to…

Age at interview 45

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Age at diagnosis 33

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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.

Age at interview 42

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Age at diagnosis 41

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Duncan prefers not to check his glucose levels every day. The strips are too expensive and also…

Age at interview 63

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Age at diagnosis 61

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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.