The EarEEG system is a novel non-invasive, unobstructed and discrete method for recording EEG in which the signal is recorded using dry-contact electrodes embedded on a customised ear piece. One intended medical indication of the EarEEG system is the detection of hypoglycaemia-induced changes in the EEG in patients with type 1 diabetes. Currently, no studies exist investigating the detection of hypoglycaemic episodes by use of ear electrodes. While a finger prick test accurately measures the blood glucose level, it does not provide continuous measurements, and hence it is unreliable as a hypoglycaemia alarm. Recent studies have indicated that the use of continuous glucose monitoring (CGM) reduces the risk of severe hypoglycaemia. However, some find these devices troublesome to use and utilisation of CGM has remained limited to date. Observational data show that only a small percentage of patients with type 1 diabetes are using CGM on an ongoing basis. Thus, there is a medical need for a reliable hypoglycaemia detection device which is easy and convenient to use.

This clinical study aims at investigating the feasibility of measuring hypoglycaemia induced changes in the EEG by use of the EarEEG system.

Inclusion Criteria:

For a subject to be eligible, all inclusion criteria must be answered "yes":

1. Informed consent obtained before any study related activities1
2. Age 18-70 years
3. Patients with type 1 diabetes (duration ≥ 5 years)

Exclusion Criteria:

For a subject to be eligible, all exclusion criteria must be answered "no":

1. Severe cardiac disease

   1. History of myocardial infarction
   2. Cardiac arrhythmia

2. Previous stroke or cerebral haemorrhage and any other structural cerebral disease

3. Uraemia defined as s-creatinine ≥ 3 times upper reference value,

4. Liver disease defined as s-ALAT ≥ 3 times upper reference interval

5. Epilepsy

6. Use of antiepileptic drugs for any purposes

7. Use of the following drugs: Chemotherapeutic drugs of any kind, methotrexate, third generation antipsychotic drugs (aripiprazole, quetiapine, clozapine, ziprasidone, paliperidone, risperidone, sertindole, amisulpride, olanzapine)

8. Known or suspected abuse of alcohol defined as estimated consumption beyond that, which is recommended by the DHA1 or any other neuro-active substances

9. Use of hearing aid or cochlear implants2

10. Allergic contact dermatitis caused by metals or generally prone to skin irritation

11. Narrow or malformed ear canals

12. Patients that are judged incapable of understanding the patient information or who are not capable of carrying through the investigation

13. Pregnancy