The Effect of Hypoglycaemia on Social Cognition and Cardiac Conduction in Adults With Type 1 Diabetes
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 16
- 试验地点
- 1
- 主要终点
- To measure changes in electrolyte levels and QT interval on electrocardiography between hypoglycaemic and euglycaemic states
研究概览
简要总结
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.
详细描述
Hypoglycaemia is a very common side-effect of insulin treatment in people with diabetes. Anglo-Danish studies have confirmed the high frequency of hypoglycaemia affecting people with type 1 diabetes. The rate of severe hypoglycaemia is as high as 0.35 episodes per patient-year.
The human brain requires a constant supply of glucose for normal functioning, which is impaired by hypoglycaemia. As a consequence, cognitive and motor function can deteriorate rapidly with significant consequences. This has been studied extensively and it is known that hypoglycaemia affects various domains of cognitive function including short-term and working memory, attention, non-verbal intelligence, visual and auditory information processing, psychomotor function, spatial awareness, and executive functioning. However, to our knowledge, the effect of acute hypoglycaemia on social cognition has not been studied previously.
Social cognition examines the higher cognitive functions involved in interpreting facial expressions, gestures or 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 who are hypoglycaemic 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 known to have an effect on the electrophysiology of the heart. It can cause prolongation of the QT interval(represents the interval between the Q wave and T wave in an ECG), demonstrable with electrocardiography which may predispose some individuals to an increased risk of cardiac arrhythmias. Studies have shown this QT interval prolongation to be associated with adrenaline secretion secondary to sympathoadrenal activation during an acute episode of hypoglycaemia and this provokes a fall in plasma potassium. Electrolyte imbalances are known to predispose to arrhythmias and it is not known if other electrolyte disturbances during hypoglycaemia may also affect the QT interval.
Using the hyperinsulinaemic glucose clamp technique, tests of social cognition will be administered during one hour of hypoglycaemia in 20 adults with type 1 diabetes. The study participants will act as their own controls by performing the same tests during euglycaemia on a separate study session separated by at least two weeks, using the same hyperinsulinaemic glucose clamp technique.
研究设计
- 研究类型
- Observational
- 观察模型
- Other
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 40 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Type 1 diabetes (insulin-treated) for at least two years duration.
- •HbA1c values between 42 mmol/mol and 97 mmol/mol within the preceding 6 months.
- •Aged 18-40 years.
- •Body mass index 18-35 kg/m2.
排除标准
- •Participants will be excluded from the study if they meet any of the following criteria:
- •Significant co-existent systemic disease or malignancy.
- •Past history of severe hypoglycaemia.
- •Past history of cardiovascular disease
- •Past history of cerebral injury, seizure, chronic alcoholism or psychiatric disorder.
- •Pregnancy. (Pregnancy testing will be carried out on all prospective female subjects).
- •Impaired awareness of hypoglycaemia (defined as a score of 4 or more on the Gold scale)
- •Use of drugs that affect heart rate and QT interval within the week before the study.
结局指标
主要结局
To measure changes in electrolyte levels and QT interval on electrocardiography between hypoglycaemic and euglycaemic states
时间窗: 4 hours (ECGs and electrolyte measurements will be taken at various timepoints during both study sessions)
Each participant attends for 2 study sessions. ECGs and electrolyte measurements are taken throughout the 4 hour study session each time.
To measure change in social cognition scores during hypoglycaemia and compare that to scores obtained while euglycaemic.
时间窗: 1 hour (experimental period is 1 hour) during each study session.
Each participant attends for 2 sessions; 1 where hypoglycaemia is induced during the experimental period and second where they are euglycaemic during the hour long experimental stage. Therefore, the time frame is one hour for measurement of social cognition.
次要结局
未报告次要终点