An existing therapy has been shown for the first time to be a safe and effective long-term treatment for people with neonatal diabetes, in a global research study involving Diabetes UK scientists at the University of Exeter.
Neonatal diabetes is a rare form of diabetes caused by changes in specific genes. Half of all cases of neonatal diabetes are caused by a change in their KCNJ11 gene – a gene involved in keeping insulin-producing cells in the pancreas working properly.
Ten years ago, researchers discovered that people with a certain type of neonatal diabetes didn’t need insulin therapy. Instead, they could use sulphonylurea tablets to manage their blood glucose, meaning they didn’t need daily injections. Sulphonylurea tablets are also used to treat Type 2 diabetes, but until now, we didn’t have information about their long-term safety and effectiveness for neonatal diabetes.
In people with Type 2 diabetes, the effects of sulphonylureas have been shown to wear off after a number of years and people commonly report having hypos. The dose needed to treat neonatal diabetes can also be up to ten times higher than that for Type 2 diabetes. It was therefore very important to study the long-term effects of the tablets in people with neonatal diabetes, to be sure they are safe and effective.
To do this, researchers studied 81 people with neonatal diabetes who had switched from insulin therapy to sulphonylurea tablets before 2006 (at least 10 years earlier). They looked at their blood glucose control, the dose of sulphonylurea they were taking, episodes of hypoglycaemia, any side effects and diabetes complications.
Safe and effective
They found that more than 9 out of 10 people taking sulphonylurea tablets (92%) had excellent blood glucose control after ten years of taking the therapy. There were no reports of severe hypos or weight gain, which is commonly seen with insulin therapy. Alongside this, no one stopped taking the tablets because of side effects and diabetes complications were rare.
Taken together, this means that high doses of sulphonylurea tablets can be taken safely and should be very effective for the long term. This is great news for people with this type of neonatal diabetes.
More research needed
Some people with neonatal diabetes also have developmental problems, such as muscle weakness, learning difficulties or epilepsy. The researchers wanted to know if long-term sulphonylurea therapy could improve or prevent these problems as well.
They found that just under half of those who had developmental issues at the start of their therapy had improved after 10 years, but it wasn’t a complete recovery. Another fifth developed issues during their ten years of therapy. Based on these results, the researchers believe that while sulphonylurea therapy provides excellent blood glucose control in the long-term, more research is needed to understand how to prevent or improve developmental problems.
Best start in life
Dr Elizabeth Robertson, Director of Research at Diabetes UK, said: "It’s so important that people living with rare forms of diabetes, like neonatal diabetes, receive the right diagnosis and treatment. That’s why we are delighted to have been able to help fund this vital work, demonstrating for the first time that sulphonylurea tablets are a safe and effective way for some people with neonatal diabetes to manage their condition for the long term. Moving forward, we hope research will uncover ways to prevent the developmental issues people with neonatal diabetes face.
"Nine out of ten people with this condition can switch from insulin therapy when they get the right diagnosis, so we would like all children diagnosed with diabetes under six months to be tested for neonatal diabetes, so the right treatment can help them get the best start in life."