TIPOS DE PROTECCIONES

It is entirely up to you to decide whether you want to take part. We will describe the study and go through the information sheet, which we will then give you. We will then ask you to sign a consent form to allow us to look at the results of the glucose tolerance test that you are having today. If you do not wish to sign this form or take part, we will not look at your results or use them for research purposes. If you do consent to us

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looking at your results, we will contact you again if they suggest you may be suitable for the research study. We will then describe the study again to you and, if you wish to take part, we will then ask you to sign a second consent form to show you have agreed. You are free to withdraw at any time, without giving a reason or explaining yourself. This would not affect the standard of care you receive.

What will happen to me if I take part?

If you agree to take part, the results of your glucose tolerance test today will be reviewed by a member of the research team. If the test is completely normal, or if it shows that you have diabetes, the results will be sent to the doctor who arranged your test, and you will hear nothing further about this research. If your glucose tolerance test shows you have ‘impaired glucose tolerance’ or impaired fasting glycaemia’, the results will be sent to the doctor who arranged your test and, in addition, you will be invited to participate in the next stage of the research project. You can, of course, decide not to take part at that stage or at any time later.

Before you leave the hospital today, you will be asked to sign a Consent Form. This will give us permission to look at the results of your glucose tolerance test and to contact you again about the research project.

If you do take part, you will be asked to attend the Diabetes Centre at the University

Hospital of Wales where we will teach you how to check your own blood glucose at home by pricking your finger and placing a spot of blood onto a stick that fits into a small meter. The meter will record the result in its memory. We will ask you to check your blood glucose at least 4 times a day for the following 6 days.

You will also be fitted with a continuous glucose monitor. This involves us placing a small piece of plastic (an electrode) just under the skin in your tummy. There is a sharp scratch, less painful than a blood test, but no other discomfort. This electrode is connected to a monitor, about half the size of a mobile telephone, which we will ask you to keep with you continuously for 3 days. We will show you how the monitor works as you will need to enter the results of your own blood glucose meter results at least 4 times a day in a written diary. You will be given a telephone number to call should the monitor become dislodged whilst you are at home. The monitor is designed to allow you to carry on with your normal work and life whilst it is connected and we would encourage you to just carry on with your normal activities.

In addition, a total of 20 ml of blood will be taken from a peripheral vein to check HbA1c, analogous markers of glycaemic control, auto- antibodies and serum lipids. After 3 days, we will ask you to return to the Diabetes Centre so that we can replace the electrode. We will then want to continue using the monitor for another 3 days before coming back so that we can disconnect it.

People with impaired glucose tolerance or impaired fasting glycaemia are at increased risk of developing diabetes in the future. You will be given some general advice as to how to reduce the risk when you come to the Diabetes Centre and this can be reinforced by your own General Practitioner who will be informed of your results.

In order to check whether diabetes has developed, it is common practice to repeat the glucose tolerance test in 12 months’ time and again the year after if necessary. We will arrange for this to be done and following these repeat glucose tolerance tests, we will ask you to use the continuous glucose again for a 6 day period. In addition, a total of 20

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ml of blood will be taken from a peripheral vein via a cannulae (2.5 ml blood every 15 minutes) to check physiological blood markers of diabetes (HbA1c, analogous markers of glycaemic control, auto- antibodies and serum lipids).

Each visit to the Diabetes Centre will take 2-3 hours. We are unable to compensate you for your loss of earnings, but we will reimburse the costs of parking at the hospital.

What will I have to do? You will:

Have to agree that we can look at the results of your glucose tolerance test to help us decide if you could take part in the monitoring study.

Attend the Diabetes Centre at the University Hospital of Wales for up to 3 hours to be taught home blood glucose monitoring and have the continuous glucose sensor fitted. Check your blood glucose levels at home using a pin-prick device and a meter at least 4 times a day for 6 days and enter the results into a paper diary.

Wear the continuous glucose monitor at home for 6 days (returning to the Diabetes Centre on day 3 to have the electrode changed).

Have a repeat glucose tolerance test and repeat the use of the glucose monitor in 12 months and 24 months’ time.

Have a blood test to check HbA1c, analogous markers of glycaemic control, auto- antibodies and serum lipids initially, 12 and 24 months later respectively.

What is the device being used?

We will use a continuous glucose monitor manufactured by Medtronic. We routinely use this device in people with diabetes, although it is currently not used to help predict people are at risk of developing diabetes in the future.

What are the alternatives?

At the moment, people who are found to have an abnormal glucose tolerance test are just given general lifestyle advice and have the test repeated every year in case they develop diabetes. If you decide not to take part in this research, you will be offered this standard follow-up.

What are the possible disadvantages, side-effects and risks of taking part?

The major disadvantage of taking part is the inconvenience of having to attend the Diabetes Centre, checking your blood glucose by a pin-prick 4 times a day, being attached to the glucose monitor for 6 days and having a blood test. Very rarely people are allergic to the plaster we use to fix the electrode to the skin. If you develop any itching or redness around the plaster, you will be asked to simply remove it. There is a

small risk of infection (less than 1 chance in 1000) at the site of the glucose monitor. If this were to occur, it would be treated with antibiotics.

What are the possible benefits to take part?

Set against the disadvantages, it may be valuable to learn blood glucose testing since you will be asked to do this in the future should you develop diabetes. Some people also find that the blood glucose results help encourage them to avoid foods that clearly put their sugar levels up.

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We cannot promise the study will help you personally, but the information we get from this study will help improve the treatment of people with abnormal glucose tolerance tests. In particular, it may be that the wearing of a continuous glucose monitor will help us predict which people are at the greatest risk of developing diabetes and this will allow us to use intensive lifestyle changes or drugs to reduce the risk.

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