Our research at the EASD

Question marks over coronavirus-diabetes link

Research worldwide has pointed to a higher-than-expected number of new diagnoses of type 1 diabetes in people who have had coronavirus. But there are question marks over whether the virus is directly triggering diabetes or if there are other factors at play.

A study funded by us, and shared at the EASD, gives important new clues by digging into the exact timings of coronavirus infection and type 1 diabetes diagnosis.

Professors Helen Colhoun and Paul McKeigue, from Public Health Scotland and the University of Edinburgh, and team studied data from 1.8 million people aged under 35 years in Scotland. They linked data on coronavirus test results to data tracking new diagnoses of type 1 diabetes from March 2020 to November 2021. During that period, 365,080 people tested positive for coronavirus, and 1,074 people were diagnosed with type 1 diabetes.

Findings showed that in children aged under 14 years, the number of new diagnoses of type 1 diabetes in Scotland during 2020-21 were 20% higher compared to average rates from the previous seven years. But it’s important to keep in mind that rates of type 1 diabetes in children do vary widely from year to year. There was no increase seen in type 1 diabetes incidence in those aged 15-34 years.

By looking at the precise dates people were diagnosed, the researchers found no evidence of a link between coronavirus infection and the onset of type 1 diabetes in children and adults 30 days or more after infection. This 30-day window is important. We know that type 1 diabetes does not develop overnight and it takes time for the symptoms to show up and people to get diagnosed. If coronavirus was triggering type 1 diabetes, there would likely be a gap between infection and a diabetes diagnosis. These findings do not confirm this and instead suggest people already had undiagnosed type 1 diabetes when they caught coronavirus.

Dr Lucy Chambers, Head of Research Communications at Diabetes UK, said:

“This study asked important questions about the timing of Covid-19 infection and a new type 1 diabetes diagnosis. While the study found an increase in type 1 diabetes diagnoses in children in Scotland during the pandemic, results suggest the children had undiagnosed type 1 diabetes when they caught Covid-19 rather than Covid-19 causing the onset of their diabetes.

“Research is ongoing to untangle the links between Covid-19 and type 1 diabetes, but whether you’ve had Covid-19 or not, it’s important to know the signs and symptoms of type 1 diabetes to look out for – the 4Ts. If you’re feeling more tired or thirsty than usual, need to go to the toilet more often, or have unexplained weight loss (thinner) it’s important so speak to your healthcare professional.”

The researchers also found clusters of both positive and negative coronavirus tests around the date of a type 1 diagnosis. And they think that links found in previous studies could be explained – at least partly – by those who developed diabetes being more likely to get tested for Covid-19.

Professor McKeigue described other potential explanations for an uptick in cases of type 1 diabetes in children. He said:

“Our findings show that causes other than Covid-19 infection itself need to be considered in relation to the increased incidence of type 1. We need to consider what has happened regarding the spread of other viruses, such as enteroviruses during the pandemic, and whether there are any other environmental factors, such as sunlight exposure and vitamin D levels, that might have altered during lockdown that might also be relevant."

This study adds another piece to a complex puzzle, but there’s still much to learn. That’s why we’ve put out a call to scientists asking for research applications that will help us to better understand the link between coronavirus and diabetes.

The ReTUNE study - new findings announced at EASD

Earlier this year, Professor Roy Taylor announced new findings from his Diabetes UK-funded project, called ReTUNE, a world-first study into type 2 diabetes remission in people with lower body weights. Today at EASD he shared the latest from this pioneering work.

While we know that obesity increases the risk of developing type 2 diabetes, 10% of people with the condition have a BMI that is not in the obesity or overweight category. 

We’ve been funding Professor Taylor’s trailblazing remission research for over 15 years. In 2011, our Counterpoint study first showed that shedding fat from inside the pancreas and liver – the two important organs involved in blood sugar control – was key to remission from type 2 in people living with obesity or overweight.

This led to our landmark DiRECT trial. The findings gave hope to millions of people who had type 2 diabetes and lived with obesity or overweight. It showed them it was possible for some people to put their condition into remission through weight loss. But we didn’t know if a similar approach could also help people with lower body weights.

To find out if losing excess fat from the liver and pancreas could also help people with lower body weights to go into remission, Professor Taylor and his ReTUNE study team put 20 people with type 2 diabetes and a BMI at or just above the healthy range (BMI below 27) on a similar low-calorie diet programme to the one in the Counterpoint trial. Everyone in the study had been diagnosed with type 2 diabetes in the last five years.  

People were supported by a medical team to stop all glucose-lowering tablets and follow a low-calorie diet (800 kcal per day), made up of formula meal replacements, like soups and shakes, and non-starchy vegetables for 2-4 weeks. This was followed by a 4-6 week weight loss maintenance period, which involved gradually going back to eating normal foods. People repeated this cycle of weight loss and maintenance up to three times, until they’d lost between 10 and 15% of their original body weight. After each cycle, the research team measured the amount of fat in their pancreas and liver and looked to see who had gone into remission. 

Following on from last year’s promising early results, the full findings from the ReTUNE study show us for the first time that people with type 2 diabetes and lower BMIs can be supported to put their type 2 into remission through a structured low-calorie diet programme. And that the key to this is losing harmful fat from the liver and pancreas.  

After 12 months, the findings showed that: 

• Participants’ BMI averaged 22.4 kg/m² at the end of the study (reduced from an average of 24.8 kg/m²). 
• About three quarters (70%) of participants went into remission from type 2 diabetes during the study, with 50% of these going into remission after the first weight loss cycle. 
• People needed to lose on average 8% of their body weight to go into remission. 
• In the 14 out of 20 people who went into remission, their average HbA1c fell from 53mmol/mol at the start of the study to 45mmol/mol. Their blood pressure dropped despite taking less medication to treat this. 
• The participants’ liver and pancreas fat levels were higher than expected at the start of the trial but then decreased to normal levels after weight loss. 

Participants reported feeling satisfied with their weight loss and health improvements and didn’t find it hard to keep the weight they'd lost off.  

Chris Askew, Chief Executive of Diabetes UK, said:

“Building on the pioneering DiRECT trial, this game-changing study from Professor Taylor and his team advances our understanding of why type 2 diabetes develops, and what can be done to treat it.  

“Our ambition is for as many people as possible to have the chance to put their type 2 diabetes into remission and live well for longer. The findings of the ReTUNE study potentially take us a significant step closer to achieving this goal by showing that remission isn’t only possible for people of certain body weights. 

“It is our hope that ReTUNE – as DiRECT did before it – will inform the development of services and support so that many more people with type 2 diabetes will have the possibility of remission open to them."

Professor Taylor said:

“This is very good news for everyone with type 2 diabetes, not only pointing the way forward for effective return to health but also challenging the misconceptions clinging to the condition.”