Scientists in the U.S. say some people experience subtle symptoms which are suggestive of a stroke without an actual stroke being diagnosed.
These strokes which they call 'whispering' strokes, can nevertheless still impair physical functioning and affect a persons quality of life.
The researchers say doctors often think that vague stroke symptoms are not necessarily significant but they nevertheless often "substantially lower a person's quality of life" and may have serious implications.
Lead author Dr. George Howard, from the University of Alabama at Birmingham, conducted a comparison of the mental and physical functioning of more than 21,000 African-American and white U.S. adults aged 45 and older.
Of the group 16,090 were symptom-free, 3,404 had stroke symptoms but no formal diagnosis, 1,491 patients had experienced a prior stroke, and 818 patients had a history of transient ischemic attacks (TIAs), also known as "mini-strokes."
All were given standard questionnaires in order to assess functional ability and the researchers found that physical functioning and, to a lesser extent mental functioning, in patients with stroke symptoms but no diagnosis, were worse than in symptom-free subjects and on par with what was noted in TIA (Transient Ischemic Attacks) patients.
Stroke patients as expected had the greatest impairments in physical and mental functioning.
The researchers say the differences between the groups were still apparent after accounting for demographic variables, health behaviors, and various stroke risk factors.
They found that symptoms of weakness or numbness were predictive of greater reductions in physical functioning, while difficulties in expression or language comprehension were tied to impairments in mental functioning.
Howard says doctors need to be more aware of stroke symptoms and need to take such symptoms seriously as they could indicate that a person has already had a small stroke, which greatly increases the risk of major stroke.
Stroke symptoms include the following:-
The onset of sudden - numbness or weakness of the face, arm, or leg (especially on one side of the body), confusion, trouble speaking, or understanding speech, trouble seeing in one or both eyes, trouble walking, dizziness, or loss of balance or coordination, severe headache with no known cause.
Emergency care must immediately be sought if someone experiences such symptoms, even to a mild degree.
Even though such symptoms do not always indicate stroke, waiting to see if the symptoms pass is not an option as stroke is the second biggest killer of U.S. adults and is also a leading cause of disability.
Strokes occur when the blood flow to the brain is interrupted; the majority of strokes are ischemic strokes, which are caused by blood clots and clot-busting drugs given shortly after the onset of stroke symptoms saves lives and reduces the possibility of damage to the heart.
Other strokes are bleeding (hemorrhagic) strokes, which happen when a blood vessel in the brain starts to leak.
TIAs often called 'ministrokes', are fleeting but can still cause irreversible damage.
The researchers found that those who had had whispering strokes gave themselves lower ratings for physical well-being, mental function, and quality of life than people with no history of stroke symptoms.
But it was unclear whether whispering strokes or poorer health came first, as whispering strokes were associated with health risks including high blood pressure and diabetes.
Dr. Howard says whispering strokes appear to be quite common.
The research is published in the journal Stroke.