Standing on one leg is a simple way to assess someone’s risk of suffering a stroke, suggests a new study.
Researchers have found struggling to balance on one leg for 20 seconds or longer is linked to an increased risk of small blood vessel damage in the brain and reduced thinking ability in otherwise healthy people with no clinical symptoms.
Study lead author Dr Yasuharu Tabara said the one-leg standing test is an easy way to determine if there are early signs of being at risk of a stroke and cognitive impairment.
Dr Tabara, associate professor at Kyoto University Graduate School of Medicine in Japan, said: “Our study found the ability to balance on one leg is an important test for brain health.
“Individuals showing poor balance on one leg should receive increased attention, as this may indicate an increased risk for brain disease and cognitive decline.”
The study, published in the journal Stroke, consisted of 841 women and 546 men, with an average age of 67.
To measure one-leg standing time, they stood with their eyes open and raised one leg.
The maximum time for keeping the leg raised was 60 seconds. The participants performed the examination twice and the better of the two times was used in the study analysis. Cerebral small vessel disease was evaluated using brain magnetic resonance imaging.
The researchers found that the inability to balance on one leg for longer than 20 seconds was associated with cerebral small vessel disease involving small infarctions (tissue death) without symptoms such as microbleeds (minute chronic brain haemorrhages).
They noted that 34.5 per cent of those with more than two infarction lesions had trouble balancing, while 16 per cent of those with one infarction lesion had trouble balancing.
Three out of ten of those with more than two “microbleed” lesions had trouble balancing, while 15.3 per cent with one microbleed lesion had trouble balancing.
Overall, those with cerebral diseases were older, had high blood pressure and had thicker carotid arteries than those who did not have cerebral small vessel disease.
However, people with more microbleeds and infarctions in the brain had shorter one-legged standing times. Short one-legged standing times were also independently linked with lower cognitive scores. Although previous studies have examined the connection between gait and physical abilities and the risk of stroke, this is among the first studies to closely examine how long a person can stand on one leg as an indication of their overall brain health.
Dr Tabara said: “One-leg standing time is a measure of postural instability and might be a consequence of the presence of brain abnormalities.” Small vessel disease typically increases with age. Loss of motor co-ordination, including balance, as well as cognitive impairment, has been suggested to represent sub-clinical brain damage.
Dr Tabara and his team also found a strong link between struggling to stand on one leg and increased age, with marked shorter one-leg standing time in patients age 60 and over.
In Scotland, one in six people will have a stroke and one in five strokes is fatal.
High blood pressure is the most important risk factor for stroke, being a factor in around half of all cases.
Around half of those who survive their stroke make a good recovery; however stroke can result in communication, cognitive, sensory and physical impairments, and mental ill- health, experts say.