Am Fam Physician. 2007;75(12):1858-1860
Background: Undiagnosed stroke occurs in a significant number of persons. Despite multiple attempts to educate the public about stroke symptoms, only 17.2 percent of more than 61,000 adults surveyed could classify all stroke symptoms and said they would contact emergency personnel if they believed someone was having a stroke. Because of this, Howard and associates evaluated the prevalence of stroke symptoms in persons with no history of stroke or transient ischemic attack (TIA). They also reviewed the association of these symptoms with risk factors from the Framingham Stroke Risk Score.
The Study: The population included a national sample of community-dwelling adults older than 45 years. The study period was from January 25, 2003, to November 30, 2005. There was oversampling from black populations and in states in the stroke belt (i.e., North Carolina, South Carolina, Georgia, Alabama, Mississippi, Tennessee, Arkansas, and Louisiana). Of the 18,462 participants, 41 percent were black and 51 percent were women. The mean age for the group was 65.8 years, with a range of 45 to 96 years.
|Has a physician ever told you that you had a stroke?|
|Has a physician ever told you that you had a mini stroke or transient ischemic attack?|
|Have you ever had sudden painless weakness on one side of your body?|
|Have you ever had sudden numbness or a dead feeling on one side of your body?|
|Have you ever had sudden painless loss of vision in one or both eyes?|
|Have you ever suddenly lost one half of your vision?|
|Have you ever suddenly lost the ability to understand what people were saying?|
|Have you ever suddenly lost the ability to express yourself verbally or in writing?|
The participants were contacted by phone, and demographic information, medical history, and quality-of-life index were obtained. The next contact was in three to four weeks for a brief physical examination, blood draw, and electrocardiography. Information about previous stroke or TIA was obtained using the Questionnaire for Verifying Stroke-Free Status (see accompanying table). The stroke risk burden for each participant was evaluated using the Framingham Stroke Risk Score. The main outcome measure was stroke symptoms.
Results: The following stroke symptoms were found in the study group: sudden hemibody numbness (8.5 percent); sudden painless hemibody weakness (5.8 percent); sudden painless loss of vision in one or both eyes (4.6 percent); sudden inability of linguistic expression (3.8 percent); sudden hemifield visual loss (3.1 percent); and sudden inability to understand speech (2.7 percent). One or more of these symptoms was present in 17.8 percent of the study population. For each increase in the Framingham Stroke Risk Score, there was a corresponding increase in the odds ratio for the presence of stroke symptoms. Black persons were more likely to have stroke symptoms compared with white persons. Participants from lower income brackets, those who had lower education levels, and those who had fair to poor perceived health status had more stroke symptoms.
Conclusion: The authors conclude that there is a significant prevalence of stroke symptoms in patients who have not had a previous stroke or TIA. They add that some persons with risk factors for stroke may have clinically undetected cerebrovascular events, and aggressive stroke prophylaxis may provide some benefit. Patient education targeting those at risk of stroke and reducing risk factors may reduce the chance of stroke.