The tell-tale signs of a stroke may be evident a decade before the life-threatening event, research suggests.
In the UK, 100,000 people have a stroke every year.
If you suspect someone has had a stroke, think FAST. Face – is it drooped?, Arms – can they be lifted?, Speech – is it slurred?, Time – to call 999.
Writing in the Journal of Neurology Neurosurgery & Psychiatry, scientists from Erasmus University Rotterdam have now revealed people may experience a decline in cognitive function up to 10 years before a stroke.
They may also struggle to wash, eat or keep on top of their finances, the results suggest.
Stroke survivors often endure a persistent decline in cognitive function or find it difficult to look after themselves.
Changes within the brain may be "already present before a first-ever stroke". Identifying those who could be more at risk may allow medics to administer preventative treatments.
To learn more, the Erasmus scientists analysed more than 14,000 participants of the Rotterdam Study.
Between 1990 and 2016, the participants underwent tests that assessed their memory, speech and reaction times. Their ability to wash, eat, dress themselves and manage their finances was also investigated.
Up until 2018, the participants' medical records were studied to tally the number of strokes that took place.
Each stroke patient was then matched against three healthy participants, according to their age and sex.
Results reveal a "clear difference" in the cognitive and daily functioning between the participants who did and did not later have a stroke.
The so-called Mini Mental State Exam – widely used to assess memory and dementia severity – threw up different results between the two groups up to eight years before a stroke.
The results of the Purdue Pegboard test – which assesses dexterity – and the Stroop task – measures the speed of mental processing – started to differ around nine and 10 years before a stroke, respectively.
The stroke patients' ability to care for themselves and their finances declined up to three years ahead of the event, the results show.
Watch: Demi Lovato reveals she had three strokes after near-fatal overdose
Stroke is often considered a leading cause of death among men.
Perhaps surprisingly, the Erasmus scientists found women were more at risk, with three in five (60%) of the stroke patients being female.
Carrying the APOE gene – associated with Alzheimer's – and having fewer academic qualifications were also linked to a stroke, with both of these considered a marker of "cognitive reserve".
The scientists have stressed the study was observational and therefore does not prove cause and effect. It is also unclear what type of stroke the patients had or how severe the event was.
Nevertheless, the scientists wrote: "Our findings demonstrated future stroke patients start to deviate from stroke-free controls up to 10 years before the acute event, suggesting individuals with cognitive and functional decline are at a higher risk of stroke and are possible candidates for prevention trials.
"The accelerated decline in cognition and daily functioning before stroke suggests individuals with future stroke suffer from accumulating intracerebral [within the cerebrum in the brain] damage years before the acute event, such as cerebral small vessel disease, neurodegeneration, and inflammation."
Watch: Recognising stroke symptoms