Regularly taking naps of at least 90 minutes in your sixties may increase your risk of having a STROKE, study warns
- People who napped for 1.5hours or more had 25 per cent increased risk of stroke
- Those who slept over nine hours a night also 23 per cent more likely to suffer one
- Researchers believe too much sleep triggers dangerous cholesterol changes
Regularly taking long naps in your sixties may increase your risk of having a stroke, research suggests.
For a long time, doctors have warned sleep deprivation triggers high blood pressure and clots in the arteries.
And experts in China have now bolstered the evidence that napping for too long or getting too much shut-eye is equally as bad.
Scientists looked at the sleeping and napping habits of more than 30,000 people over the age of 60, tracking them for six years.
They found those who regularly napped for more than an hour-and-a-half during the day were 25 per cent more likely to suffer a stroke, compared to people who did not.
Over-60s who nap for more than an hour-and-a-half during the day are 25 per cent more likely to suffer a stroke than people who do not, research suggests (stock)
But there was no increased risk of suffering one if people napped for less than an hour, results showed.
Volunteers who slept for more than nine hours a night were also at a 23 per cent increased risk, compared to people who got seven to eight hours.
And people who were both long nappers and long sleepers were 85 per cent more likely to later have a stroke.
As the study was an observational one, the researchers – from Huazhong University in Wuhan – say they are unsure why oversleeping causes the increased risk.
But they believe too much rest may disrupt blood supply to the brain and cause a build-up of cholesterol in the arteries.
They also said regularly napping during the day may indicate an inactive lifestyle – another known risk of a stroke.
The team looked at 31,750 healthy people with an average age of 62 as part of their study.
They were followed for an average of six years and during that time there were 1,557 strokes. Participants filled out questionnaires about their sleeping and napping habits.
The results were adjusted for other factors that could affect the risk of stroke, such as high blood pressure, diabetes and smoking.
Study author Xiaomin Zhang said: ‘More research is needed to understand how taking long naps and sleeping longer hours at night may be tied to an increased risk of stroke.
‘But previous studies have shown that long nappers and sleepers have unfavorable changes in their cholesterol levels and increased waist circumferences, both of which are risk factors for stroke.
‘In addition, long napping and sleeping may suggest an overall inactive lifestyle, which is also related to increased risk of stroke.
‘These results highlight the importance of moderate napping and sleeping duration and maintaining good sleep quality, especially in middle-age and older adults.’
Limitations of the study include that information on sleep and napping was taken from questionnaires, not from recording actual sleep. They also did not specify what counted as ‘regular napping’.
The findings were published in Neurology, the medical journal of the American Academy of Neurology.