When patients with type 1 diabetes eat, they inject insulin to reduce glucose in their blood to a safe level.
However, if too much insulin is injected, it leads to something called hypoglycaemia - dangerously low levels of glucose in the blood. Because the brain needs glucose to function properly, someone suffering from hypoglycaemia can become dizzy, giggly, confused and will eventually become unconscious. In extreme cases they may suffer from seizures or even die.
Most patients with type 1 diabetes experience some hypoglycaemia and as soon as they recognise the symptoms, they will eat something sweet to increase their blood glucose to a , and use of newer technologies for monitoring blood glucose and taking insulin can help. But one in ten (around 30,000 people in the UK) lose the ability to recognise mild hypoglycaemia and suffer from severe episodes regularly; some may have an episode at least once a day.
Research by Professor Stephanie Amiel and Dr Pratik Choudhary at King’s is aimed at understanding more about why these people struggle to avoid severe hypoglycaemia.
Professor Amiel said: “When the brain doesn’t have enough glucose, the body has a stress response. This response includes a negative reaction, so that the person does everything they can to avoid it happening again. However, if a person regularly has hypoglycaemic episodes, over time the brain stops recognising it. It no longer produces a stress response or symptoms, It may also no longer recognise the hypoglycaemia as being bad.”
As part of their research Professor Amiel and Dr Choudhary looked at brain scans of patients who have frequent hypoglycaemic episodes.
Professor Amiel said: “The scans revealed those patients who had poor awareness of hypoglycaemia did not have a negative emotional response, as would be expected when the body is going through a stressful situation like this."
“Because they did not have the negative reaction, those people found it hard to adjust their diabetes management, even when close monitoring of their blood revealed that their insulin levels were too high for them. They did not prioritise avoiding hypoglycaemia, in part because it did not feel bad for them.”
Professor Amiel and Dr Choudhary are now looking at whether a form of therapy based on psychological approaches can help.
Dr Choudhary added: “We are running a clinical trial looking at whether this leads to better avoidance of hypglycaemia. It’s a form of therapy using elements of cognitive behavioural therapy, and other techniques, but delivered by diabetes educators (nurses and dietitians), supported by psychologists. We help people understand how their thoughts about hypoglycaemia create barriers to hypoglycaemia avoidance, and help them adjust their behaviour around hypoglycaemia to prevent severe episodes. The programme is called HARPdoc, which stands for Hypoglycaemia Awareness Restoration Programme, for people with type 1 diabetes and problematic hypoglycaemia persisting despite optimised control. In an early pilot study, people, who had been having severe hypoglycaemia for years were able to stop having them."
Professor Amiel and Dr Choudhary are currently recruiting patients to this trial.
King’s has also been awarded €1.5million of a €27million EU grant to assess the impact on people of hypoglycaemic episodes. Part of this research will look at the effect on people with type 2 diabetes, who can suffer from severe hypoglycaemia if they have had their diabetes for a number of years.
Dr Choudhary said: “Those patients tend to be older. As time goes on, they have had to start injecting insulin and so they are at higher risk of becoming hypoglycaemic. Because they are older, the impact of such an episode tends to be more serious. This research is aimed at understanding more about what happens to those patients as well as the long term impact of t hypoglycaemic episodes on people with type 1.”