Behind the headlines: can more teenage sleep really ward off MS?
You may have seen stories in the papers today about a link between the sleep you get as a teenager, and your risk of MS. We look behind the headlines to see what the research can tell us.
Researchers from Sweden have asked if the amount of sleep teenagers get could affect their risk of developing MS later on. And in the findings they've published, they do report a link. But researching MS risk factors is challenging. So we need to interpret the results with caution.
Why did the researchers explore a link between sleep and MS?
Some risk factors, like low vitamin D and infection with the Epstein Barr Virus have been well studied. But it’s important we find out more about what might increase the risk of developing MS, because we know there’s no one thing that causes MS. We think it’s caused by a combination of your genetics, lifestyle and environment.
The authors of this sleep research have published previous work suggesting shift-workers might be more likely to get MS. One reason for this could be that shift-work disrupts sleep patterns. And scientists have shown not getting enough sleep can affect the immune system. It might even cause damage to nerves.
So they wanted to explore a potential link between sleep and MS further.
Read about previous research on shift work and MS
How did they do the research?
The data came from a large study. People with MS across Sweden have been filling in questionnaires over many years. A bit like our UK MS Register.
The researchers asked people to reflect on sleep habits when they were 15 to 19 years old. They asked what time they normally went to bed and woke up. They asked if that was different on school and work days compared to weekends and holidays. They also asked how they’d rank their sleep quality.
They took into account other risk factors. Like how much time people spent in the sun, if they smoked, and whether they’d had glandular fever.
They analysed data from 2,075 people with MS and 3,164 people without MS.
What did they find?
The researchers divided people into 3 groups. People who said they slept:
- less than 7 hours a night
- 7-9 hours a night
- more than 10 hours a night
People who had the least sleep (less than 7 hours) had a higher chance of developing MS than people in the middle group (7-9 hours). This was still true when they removed shift workers from their calculations. So the difference wasn't explained by shift work.
People who said they had a lower quality of sleep also had an increased risk of developing MS.
Why do we need to be cautious about how we interpret the findings?
We need to be cautious about these findings for a few reasons. One big one is that the information about people's sleep was retrospective. People had to try to remember details from years earlier. It’s possible people with MS remembered their sleep habits differently.
And we know MS can start to develop long before someone's diagnosed with it. So it’s also possible a lack of sleep as a teenager could actually be the result of MS rather than the other way round.
There might also be other factors linked to sleep patterns that affect MS risk, but weren’t studied by the researchers. Like diet or stress.
What does this mean for someone with MS?
Getting enough sleep as a teenager, and as an adult, is important for lots of reasons. Sleep can help things like mood and fatigue. So trying to make sure you’re sleeping well, is unlikely to do any harm.
But we need more research to know for sure whether reduced sleep does play a role in increasing the risk of MS. Future research could involve, for example, using smart watches to monitor sleep in real-time.
And even if poor sleep is a risk factor for MS, it’s probably only a small part of the story.
Read the full paper in the Journal of Neurology, Neurosurgery and Psychiatry
