Automated detection of hypoglycemia-induced EEG changes recorded by subcutaneous electrodes in subjects with type 1 diabetes--the brain as a biosensor

TY - JOUR

T1 - Automated detection of hypoglycemia-induced EEG changes recorded by subcutaneous electrodes in subjects with type 1 diabetes--the brain as a biosensor

AU - Juhl, Claus B.

AU - Højlund, Kurt

AU - Elsborg, Rasmus

AU - Poulsen, Mikael Kjaer

AU - Selmar, Peter E

AU - Holst, Jens Juul

AU - Christiansen, Claus

AU - Beck-Nielsen, Henning

PY - 2010/4/1

Y1 - 2010/4/1

N2 - Aims: Hypoglycemia unawareness is a common condition associated with increased risk of severe hypoglycemia. We test the hypothesis that specific changes in the electroencephalogram (EEG) during hypoglycemia can be recorded by subcutaneous electrodes and processed by a general mathematical algorithm, and that hypoglycemia associated EEG changes appear before the development of severe hypoglycemia. Methods: Fifteen patients with type 1 diabetes were exposed to insulin-induced hypoglycemia and EEG was recorded. The cognitive function was evaluated by repeated cognitive testing. Insulin infusion was terminated when plasma glucose reached 1.8 mmol/l or when the subjects showed obvious signs of cognitive dysfunction. EEG was analyzed by an automated mathematical algorithm with a predefined threshold of hypoglycemia. Results: Hypoglycemia associated EEG changes were detected by the mathematical algorithm in all subjects. Plasma glucose at the time of EEG changes above the threshold value ranged from 2.0 to 3.4 mmol/l and occurred 29 ± 28 min (range 3-113 min) before termination of insulin infusion. Conclusions: Hypoglycemia associated EEG changes could be detected by an automated mathematical algorithm in all subjects exposed to insulin-induced hypoglycemia. In 12 of 15 patients, EEG changes occurred before severe hypoglycemia as evaluated by the cognitive testing.

AB - Aims: Hypoglycemia unawareness is a common condition associated with increased risk of severe hypoglycemia. We test the hypothesis that specific changes in the electroencephalogram (EEG) during hypoglycemia can be recorded by subcutaneous electrodes and processed by a general mathematical algorithm, and that hypoglycemia associated EEG changes appear before the development of severe hypoglycemia. Methods: Fifteen patients with type 1 diabetes were exposed to insulin-induced hypoglycemia and EEG was recorded. The cognitive function was evaluated by repeated cognitive testing. Insulin infusion was terminated when plasma glucose reached 1.8 mmol/l or when the subjects showed obvious signs of cognitive dysfunction. EEG was analyzed by an automated mathematical algorithm with a predefined threshold of hypoglycemia. Results: Hypoglycemia associated EEG changes were detected by the mathematical algorithm in all subjects. Plasma glucose at the time of EEG changes above the threshold value ranged from 2.0 to 3.4 mmol/l and occurred 29 ± 28 min (range 3-113 min) before termination of insulin infusion. Conclusions: Hypoglycemia associated EEG changes could be detected by an automated mathematical algorithm in all subjects exposed to insulin-induced hypoglycemia. In 12 of 15 patients, EEG changes occurred before severe hypoglycemia as evaluated by the cognitive testing.

KW - Adult

KW - Algorithms

KW - Cerebral Cortex

KW - Cognition

KW - Diabetes Mellitus, Type 1

KW - Electrodes, Implanted

KW - Electroencephalography

KW - Female

KW - Humans

KW - Hypoglycemia

KW - Male

KW - Middle Aged

KW - Neuropsychological Tests

U2 - 10.1016/j.diabres.2010.01.007

DO - 10.1016/j.diabres.2010.01.007

M3 - Journal article

C2 - 20074827

SN - 0168-8227

VL - 88

SP - 22

EP - 28

JO - Diabetes Research and Clinical Practice

JF - Diabetes Research and Clinical Practice

IS - 1

ER -