Our research has revealed that insomnia may cause high blood sugar levels, directly increasing the risk of developing type 2 diabetes. The findings suggest that treatments that tackle insomnia could help to prevent or treat the condition.
We know from past research that there’s a link between sleep and a person’s risk of type 2 diabetes, but it hasn’t been clear which comes first – bad sleep or higher blood sugars, or if other factors are at play.
To help unravel this, a study we funded led by the University of Bristol and supported by the universities of Manchester, Exeter, and Harvard studied the sleep behaviours and blood sugar levels of 337,000 adults living in the UK.
Putting cause and effect to bed
Using data from the UK Biobank study, researchers used Mendelian randomisation – a statistical method that uses genetic and health information to understand cause and effect. They explored if five different sleep traits were directly related to HbA1c levels to better understand their role in the development of type 2 diabetes. These traits were:
- insomnia symptoms
- sleep duration
- daytime sleepiness
- napping
- being a morning or evening person
They found that people who reported often having difficulty getting to sleep or staying asleep had higher blood sugar levels than people who said they never, rarely, or only sometimes had these insomnia symptoms. There was no evidence that the other sleep factors they measured had any impact on blood sugar levels.
Treating sleep to target type 2
These findings help us better understand how sleep problems can influence the development of type 2 diabetes.
Dr Faye Riley, our Research Communications Manager, said:
"This new study, funded by Diabetes UK, gives us important insights into the direction of the relationship between sleep and type 2 diabetes, suggesting that insufficient sleep can cause higher blood sugars levels and could play a direct role in the development of type 2 diabetes. Knowing this could open up new approaches to help prevent or manage the condition."
James Liu, Senior Research Associate in the Bristol Medical School and MRC Integrative Epidemiology Unit, said:
“We estimated that an effective insomnia treatment could result in more glucose lowering than an equivalent intervention which reduces body weight. This means around 27,300 UK adults, aged between 40- and 70-years-old, with frequent insomnia symptoms could benefit if their insomnia was treated.”
Treatment for insomnia include cognitive behavioural therapy (CBT), along with short-term use of sleeping tablets or a hormone (called melatonin) if CBT doesn’t work. Future studies that look at the impact of these treatments on blood sugar levels will be vital to find out if targeting insomnia could help people with or at risk of type 2 diabetes.
This study also doesn’t tell us anything about what's going on inside the body to explain the link between insomnia and blood sugars. One possibility is that hormones, which are influenced by disturbed sleep, also effect how the body handles glucose. But we need more research to explore the biological processes at play.
If you're worried about your sleeping, read some tips for a good night sleep.
Photo by Lux Graves on Unsplash
