Stroke and transient ischaemic attack awareness

Studies of acute intervention for stroke have shown that outcomes are more favourable if symptoms are recognised early. However, most people do not seek medical attention soon enough.1-4 Many factors contribute to delays in seeking medical treatment for acute stroke, but one that can be addressed is the public lack of knowledge about symptoms, which often means a delay in seeking medical care.5

Fast access to acute medical services, particularly thrombolysis, is an important predictor of stroke outcome.6-8 There has been much research and discussion recently about the need for urgent investigation and treatment of patients who present with symptoms of transient ischaemic attack (TIA) or stroke.9,10

To benefit from early intervention, the patient must first recognise the symptoms of TIA or stroke, then seek medical attention, and have appropriate investigations and then treatments in a suitable time frame. The inability of patients and bystanders to recognise the symptoms and signs of stroke and to quickly access the emergency medical system are the largest barriers to effective stroke therapy, in particular thrombolysis and carotid endarterectomy. Population-based studies demonstrate sub-optimal awareness of stroke risk factors and warning signs for stroke onset.11,12 Contemporary Australian data on stroke awareness in the general population is scarce.13,14

In September 2009, the National Stroke Foundation organised National Stroke Week, to raise awareness of stroke and its early warning signs using the Face, Arms, Speech, Time (FAST) test. This has been designed as a simple tool for the general public to recognise and remember the signs of stroke, as well as emphasising that time is critical. It involves asking three simple questions:

• Face: check the patient’s face. Has their mouth drooped?

• Arms: can they lift both arms?

• Speech: is their speech slurred? Do they understand you?

• Time: time is critical. If you see any of these signs, call 000 now!

The aims of our study were to investigate public awareness of the symptoms, signs and risk factors of TIA and stroke, and what people would do if they occurred. We also investigated whether public knowledge of the FAST test and levels of awareness improved after the Stroke Foundation’s campaign.

A simple survey was conducted in Adelaide, South Australia. After the appropriate council permits were obtained, medical and nursing students approached members of the public in a busy city shopping mall. Subjects were randomly selected, with interviewers selecting the first person passing through a nominated point after having finished the previous interview. The questions were asked during a one-to-one interview. The interviewer intervened only to clarify a question, if required. No attempt was made to prompt the respondent by suggesting answers directly. The Flinders Clinical Research Ethics Committee approved this study.

The survey included questions on demographics and self-reported health status, including risk factors for stroke. Respondents were asked which symptoms and signs from a given list (Box 2)12 were warning signs of a stroke or TIA. A typical acute stroke presentation was then described to them (eg, “If you suddenly developed some weakness in your right arm and leg, what would you do?”) and they were asked if they would:

a. see their GP the next day,

b. go to their GP that day

c. go to the emergency department (ED) immediately; or

d. other.

Respondents were also asked if they had heard of the FAST test and, if so, what the acronym stood for.

This survey was conducted on three separate occasions: before, immediately after, and 3 months after National Stroke Week.

All statistical analyses were performed using SPSS version 13 (SPSS Inc, Chicago, Ill, USA). Fisher exact and χ2 tests were performed to compare differences in knowledge base between groups. Analysis of variance was used to look at the mean differences in numbers of correct answers between the three survey times.

A total of 251 members of the general public completed the survey (85, 83 and 83 respondents before, immediately after and 3 months after National Stroke Week, respectively) Box 1.

A summary of the respondents’ knowledge of stroke warning signs and risk factors is presented in Box 2. Warning signs identified by at least 5% of the study sample are shown. The most commonly identified were slurred speech, dizziness, numbness and visual disturbances. However, with the exception of slurred speech (identified by 61%), fewer than half the population identified these established warning signs. Twelve percent of the respondents were not able to identify any warning signs for stroke.

Stroke risk factors identified by at least 5% of the three study samples are shown in Box 2. The most commonly identified were hypertension, smoking, obesity and high cholesterol. However, with the exception of hypertension (identified by 71%) and smoking (53%), fewer than half the population correctly identified established stroke risk factors.

The type of stroke symptoms presented to the respondents in the stroke scenario significantly affected their responses to the questions about what they would do if they developed weakness in their right arm and leg (Box 3). Slurred speech was the only single identified symptom resulting in > 50% of respondents saying they would attend the ED immediately. The identification of both slurred speech and limb sensory loss as stroke symptoms resulted in the greatest number saying they would attend the ED (62%). There were no significant differences in the results following National Stroke Week.

Before National Stroke Week, only 22% of the population had heard of FAST. This increased to 40% immediately after, and 39% at 3 months (P < 0.05). However, only 30% of people who had heard of FAST were able to describe what it meant, and only 7% could accurately describe all four components of the acronym 3 months after National Stroke Week (Box 4).

Analysis of the association between demographic factors and correct identification of stroke risk factors and warning signs (which we defined as accurate identification of two or more items) showed no significant associations. Subjects who had heart disease, or who had already had a stroke or a TIA, did not have a better knowledge of stroke warning signs. Good knowledge of FAST was not associated with an improvement in stroke knowledge (Box 5).

Early recognition of stroke symptoms and signs is key to early interventions and more favourable stroke outcomes. Major health organisations, including the National Stroke Foundation, have targeted public education, using television, newsprint, educational pamphlets and health seminars. Collecting baseline data about knowledge of stroke in a population can help these organisations to determine the effectiveness of their programs and target them appropriately. Despite educational campaigns, public knowledge of the signs, symptoms, and risk factors for stroke remains poor. Previous surveys of the general public suggest that up to 27% of adults can not name any signs or symptoms of stroke, and up to 25% can not identify any risk factors.15,16

Our survey found that knowledge of stroke warning signs was poor among South Australian adults despite an awareness campaign run by the National Stroke Foundation in September 2009. Slurred speech was the only warning sign identified by more than half the respondents. Notably, one in 10 could not identify any warning signs even when presented with a list of them.

Hypertension was identified most frequently as a risk factor for stroke, followed by smoking and obesity. These findings were similar to those previously reported.15 However, just over half recognised smoking as a risk factor, and all other risk factors were identified by fewer than 50% of respondents.

Mass media campaigns to improve public awareness of stroke warning signs have been found to be effective in improving knowledge of warning signs (though not of stroke risk factors),11,12,17 particularly in younger age groups. These campaigns have been found to be less effective for those aged over 65 years.11,17

This study also highlights difficulties in measuring stroke awareness. It is probable that awareness is overestimated by the use of aided questions and underestimated by unaided questions. In fact, neither approach simulates the reality of needing to make a spontaneous connection between a stroke sign and a stroke. The aided question suggests the unlikely scenario in which a person having a stroke says, “My right arm feels weak. Do you think I’m having a stroke?” In contrast, the unaided question measures only knowledge that can be spontaneously recalled. Perhaps a “partially aided” question would more closely approximate the situation in which a person needs to recognise a potential stroke (eg, “A person tells you ‘I’ve just noticed my arm feels numb.’ What would you do? What do you think this person’s problem is?”).

Another potential drawback to the study was its limited response rate (we had a 20% non-response rate of people declining to participate) which may have been a source of selection bias. However, even if non-respondents had considerably greater knowledge of stroke than study participants, overall stroke awareness would still be low enough to warrant public health action. Non-response also might have biased the estimates for the predictors of stroke knowledge, but this seems unlikely because to be a confounder, non-response would have to be associated with both the predictor and stroke knowledge.

Given these limitations, we defined awareness by using results from an aided question, which makes the results more disappointing.

Knowledge of stroke warning signs showed very little improvement after the FAST campaign. Understanding that there are potential treatments that might help reverse the problem is a well known key determinant of patient behaviour. Within a population of 1.3 million, with widespread access to public media and the internet, it is not possible to track how many stroke educational messages were delivered, nor how many other health messages for other disease states competed for their attention at the same time. One potential explanation for the poor improvement in knowledge of stroke is that there may be a theoretical limit to how much knowledge the public can absorb from such educational campaigns. A more likely explanation for the apparently poor result is that the national and local stroke awareness campaigns were not targeted appropriately at the intended audience nor tested for efficacy before implementation. Clearly, scientific study of the effectiveness of stroke educational efforts at individual and aggregate levels is warranted.

Increased knowledge of acute stroke treatments may motivate the public to translate their knowledge into action and present for medical attention more quickly. This may be the highest yield approach to increasing rates of treatment of ischaemic stroke with thrombolysis or carotid endarterectomy.