Effect of Hypoglycaemia on Social Cognition and Cardiac Conduction

It is known that hypoglycaemia affects various domains of cognitive function. One aspect of cognitive function is 'social cognition', which is our ability to interpret facial expressions, gestures and speech. It is an approach to understanding human judgement and behaviour. There is anecdotal evidence for negative behavioural responses such as aggressiveness and argumentativeness during hypoglycaemia and while research has shown that hypoglycaemia can cause significant changes in mood, little information exists regarding its effect on social cognition. It is therefore not known whether hypoglycaemia affects this aspect of cognitive function but, if it did, it could explain why people with low blood sugar due to insulin treatment are often resistant to offers of help (for example, they may misinterpret a friendly gesture as being threatening). Knowledge of this effect of hypoglycaemia can be used to educate relatives and carers of people with diabetes who may suffer this problem. Hypoglycaemia is also known to have an effect on the electrical rhythm of the heart. This is thought to be secondary to adrenaline secretion during hypoglycaemia which provokes a fall in the blood level of potassium, a type of electrolyte. Other electrolyte imbalances are known to predispose to heart rhythm abnormalities or arrhythmias in other situations and it is not known if the levels of these other electrolytes are affected during hypoglycaemia. Using specific tests of social cognition and continuous electrocardiographic (ECG) monitoring, this study aims to find out whether social cognition is affected by an hour of hypoglycaemia and how hypoglycaemia affects blood electrolyte levels and the electrophysiology of the heart.