Diabetes is a chronic and serious condition, which consumes approximately 10 per cent of the NHS budget. It can cause morbidity, loss of employment and significant cost to the individuals affected and their families. This could be avoidable were we to adopt a long-term preventive strategy. Evidence dictates that good control of diabetes, combined with appropriate measures to normalise blood pressure and the level of cholesterol in the blood, will dramatically minimise the onset of serious complications.

Diabetes is a life-long condition. The level of blood glucose is affected by various factors, which impinge daily on the lives of people with diabetes. Therefore, only the person with diabetes can supervise the level of blood glucose effectively. The task of health professionals is to train people with diabetes and their families in self-management, providing them with the appropriate skills and tools. It is vital to appreciate that diabetes education, which requires tapering to the individual in layman's terms, will need reinforcing and is time consuming. Sadly, the latter is rarely taken into account in the provision of care for diabetes. Self-management involves the ability to check the effect of therapy, diet, and activity on the level of blood glucose (home blood glucose monitoring).

What is the difference between checking for glucose in the urine and glucose in the blood?

Only when the level of glucose in the blood rises above 10 mmol/litre does glucose appear in the urine, referred to as the renal threshold. A negative result of glucose in urine may therefore be due to a normal level of glucose in the blood (4-6 mmol/litre in the fasting and pre-prandial states), a low level of glucose (less than 4) or unacceptable levels of 8 to 10 mmol/litre. Urine testing is therefore a fairly crude method of monitoring the degree of control. However, in a significant number of people, and during the early phases of the condition, this method may well be sufficient. Measurement of glucose in the blood will, however, indicate the actual level of glucose in the blood at the time of testing.

The individual is enabled to see quite dramatically, the effect of different types of physical activity or when they eat a new food preparation. They should be encouraged to do this exercise provided they have been given instructions on how to interpret the results.

How are these tests carried out?

Testing urine for glucose is quite simple. It involves dipping a test strip in the urine and this results in change of colour. Measuring glucose in the blood involves the use of a meter, a large variety of which is now available. One has to prick the finger to obtain blood, which is then put on a test strip inserted in the meter. The level of glucose is displayed after seconds. It is necessary to recognise that these are invasive tests although there are expensive non-invasive meters available. It is unfortunate that there are no meters available for the blind; talking meters were withdrawn some years ago.

When to initiate home blood glucose monitoring?

For those people who require insulin it is desirable that such individuals are given instructions on how to monitor the level of blood glucose. For those who have developed Type 2 diabetes - a condition which can be controlled by diet or tablets - it is better, in the early period of management, to devote time to talk to the individual about management and respond to anxieties rather than spend time on teaching blood glucose monitoring. Time and experience will dictate when to initiate blood glucose monitoring.

How often should tests be carried out?

It is difficult to generalise. Suffice it to say that it is important to obtain a profile of blood glucose results throughout the day; the standard times for testing are before breakfast, before midday meal, before evening meal and before going to bed. It would be fair to state that in Type 2 diabetes, glucose levels do not change dramatically and, in the majority of individuals, a profile once or twice a week is sufficient to assess the effect of therapy and to enable adjustments to be made. In those commencing insulin therapy it will be necessary for daily blood tests in the first few weeks of therapy, to enable appropriate adjustments of the dose of insulin. Once such people are stabilised on therapy they need not undertake daily testing.

What is the purpose of testing glucose levels at home?

Were testing blood glucose solely a recording exercise, it would be an enormous waste of resources. It is vital that people with diabetes who are undertaking this exercise are taught what to do with the results they obtain. They will need to be trained on how to adjust their therapy based on blood glucose levels. This is time consuming and has to be repeated. Each consultation with health professionals must be treated as an educational opportunity; the home readings should be used as an educational tool to explain how to make dose adjustments. People with diabetes should be encouraged to change therapy based on their readings; otherwise, it will be a meaningless exercise.

The ability to test one's blood glucose is a significant tool for self-education. The individual is enabled to see quite dramatically, the effect of different types of physical activity or when they eat a new food preparation. They should be encouraged to do this exercise provided they have been given instructions on how to interpret the results.

Who can initiate blood glucose monitoring?

It is not too difficult for any health professional to learn how to use a meter and to be able to instruct others on its use. However it is relevant to note that instruction on the use of meters does take time, and the learner must demonstrate proficiency in the use of the meter. Furthermore it is not sufficient to merely ensure correct use of the meter but this should be followed by education on how to interpret the results and what to do with them. Again, this is time consuming.

A major difficulty faced by health professionals who do not deal with meters frequently, and on a daily basis, is to be able to deal with the vast range of meters currently available - each with subtle differences. It may be tempting to suggest that the practice should be standardised as to the range of meters to be used. This will result in an unacceptable denial of choice to people with diabetes. It is therefore important that each district should have a resource centre where staff are well acquainted with the variety of meters and are able to advise and deal with difficulties as and when they arise. Others who are authorised to initiate glucose monitoring should receive appropriate training, and there should be a mechanism to audit their performance. It is also important to undertake an annual check of not only the meter but also the technique used by individuals with diabetes.

The correct use of home blood glucose monitoring, combined with appropriate education, offers us the enormous opportunity to reduce the expensive complications of diabetes and the burden on the NHS.

Arun K Baksi, ConsultantPhysician, & Pat Wilson, SeniorDiabetes Nurse Specialist,St Mary's Hospital, Isle of Wight Healthcare NHS Trust. Dr Baksi won the Outstanding Achieverof the Year (Doctor) Award,2003, at this year's NHS Health and Social Care Awards