A knowledge-based electrocardiogram-monitoring system for detection of the onset of nocturnal hypoglycaemia in type 1 diabetic patients

Nocturnal hypoglycaemia has been implicated in the sudden deaths of young people with diabetes. Experimental hypoglycaemia has been found to prolong the ventricular repolarisation and to affect the T wave morphology. It is postulated that abnormally low blood glucose could in certain circumstances, be responsible for the development of a fatal cardiac arrhythmia. We have designed a monitoring and alarm system for detection of the onset of spontaneous nocturnal hypoglycaemia through monitoring of the electrocardiogram. The system incorporates expert- knowledge in the form of a rule-base. It performs monitoring of two ECG features and raises alarms if abnormalities are detected corresponding to hypoglycaemia. The top performance of the system is 100% and 91.30% for sensitivity and specificity respectively. This study supports the hypothesis proposing a relationship between cardiac function and abnormally low blood glucose.