Detection of hypoglycemia associated EEG changes during sleep in type 1 diabetes mellitus.
OBJECTIVE
Nocturnal hypoglycemia is a feared complication to insulin treated diabetes. Impaired awareness of hypoglycemia (IAH) increases the risk of severe hypoglycemia. EEG changes are demonstrated during daytime hypoglycemia. In this explorative study, we test the hypothesis that specific hypoglycemia-associated EEG-changes occur during sleep and are detectable in time for the patient to take action.


METHODS
Ten patients with type 1 diabetes (duration 23.7 years) with IAH were exposed to insulin-induced hypoglycemia during the daytime and during sleep. EEG was recorded and analyzed real-time by an automated multi-parameter algorithm. Participants received an auditory alarm when EEG changes met a predefined threshold, and were instructed to consume a meal.


RESULTS
Seven out of eight participants developed hypoglycemia-associated EEG changes during daytime. During sleep, nine out of ten developed EEG changes (mean BG 2.0 mmol/l). Eight were awakened by the alarm. Four corrected hypoglycemia (mean BG 2.2 mmol/l), while four (mean BG 1.9 mmol/l) received glucose infusion. Two had false alarms. EEG-changes occurred irrespective of sleep stage. Post hoc improvement indicates the possibility of earlier detection of hypoglycemia.


CONCLUSIONS
Continuous EEG monitoring and automated real-time analysis may constitute a novel technique for a hypoglycemia alarm in patients with IAH.
Department of Endocrinology, Odense University Hospital, Odense, Denmark. lss@dadlnet.dk
Lena Sønder
LS
Snogdal
Lars
L
Folkestad
Rasmus
R
Elsborg
Line Sofie
LS
Remvig
Henning
H
Beck-Nielsen
Birger
B
Thorsteinsson
Poul
P
Jennum
Michaela
M
Gjerstad
Claus B
CB
Juhl
D000465:Algorithms; D001364:Awareness; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D056902:Clinical Alarms; D003718:Denmark; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D004569:Electroencephalography; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007003:Hypoglycemia / Q000097:blood*; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D007328:Insulin / Q000008:administration & dosage / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000379:methods; D011237:Predictive Value of Tests; D012890:Sleep; D013997:Time Factors
D015415:Biomarkers; D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; C517652:hemoglobin A1c protein, human