Tableaux de données probantes et liste de référence
The results from many cross-sectional surveys indicate that, among members of the general public, knowledge of the signs and symptoms associated with stroke is poor. Failure of recognition on the part of either those witnessing a stroke or the person experiencing a stroke event can delay the time to contact emergency services, which may in turn decrease a patient’s opportunity to receive time-sensitive treatment. Mochari-Greenberger et al. (2014) surveyed 1,205 women aged ≥25 years living in the United States who had participated in the American Heart Association National Women’s Tracking Survey. Participants were contacted by telephone and asked standardized questions related to stroke warning signs and actions to take in the event of stroke. Sudden weakness and/or numbness of the face or limb of one side were the most commonly-cited symptom (51%). Loss of/trouble with understanding speech was also frequently recognized as a symptom (44%), while headache, unexplained dizziness and loss of vision in one eye were only recognized by 23%, 20% and 18% of respondents, respectively. One in 5 women could not name any of the stroke warning signs. Lundelin et al. (2012) conducted telephone surveys of 11,827 adults living in Spain who had participated in the Study on Nutrition & Cardiovascular Risk in Spain study to assess their ability to identify stroke symptoms, including sudden confusion or trouble speaking, numbness of face, arm or leg, sudden trouble seeing in one or both eyes, sudden chest pain (decoy), sudden trouble walking, dizziness or loss of balance and severe headache. 65.2% of the participants could correctly identify 4-6 symptoms of stroke, although only 19% could identify all 6 symptoms correctly and 11.4% were unable to identify a single symptom. 81.1% of participants indicated that they would call an ambulance if they suspected someone was having a stroke. Persons who could identify more stroke symptoms were more likely to call for an ambulance.
Even after an individual has suffered a stroke, they may remain unaware of stroke risk factors, including their own. Of 195 patients admitted to hospital following a confirmed stroke or TIA, a high percentage could not identify their own stroke risk factors (Soomann et al. 2015). Diabetes was the best recognized risk factor (89%), while 78% and 77% of patients were aware of atrial fibrillation and previous stroke, respectively. Sundseth et al. (2014) reported that among 287 patients admitted to hospital with a suspected stroke or TIA, 43.2% were able to name at least one stroke risk factor, while 13.9% could identify two and 1.7% knew three. Smoking and hypertension were the two most commonly cited risk factors for stroke. In terms of their knowledge of the signs and symptoms of stroke, 70.7% of patients knew at least one symptom of stroke. 66.6% identified numbness or weakness of the face, arm or leg, 45.6% identified confusion or trouble speaking or understanding speech, while 42.9% patients were able to identify both symptoms.
The number of public awareness campaigns designed to increase the recognition of the signs and symptoms of stroke has increased over the past decade. One of the most recognized programs is FAST, a mnemonic standing for F-face drooping, A-arm weakness, S-speech difficulties and T-time to call 911. The results of several studies evaluating the effectiveness of these campaigns indicates that exposure is associated with increased awareness of the signs and symptoms of stroke. Bray et al. (2013) surveyed 12,439 individuals ≥40 years of age from the general population in Australia and reported that from 2004 to 2010 there was a significant increase in the number of respondents who were aware of the national multimedia stroke awareness campaigns (31% vs 50%), which included FAST. The authors also reported an increase in the number of participants able to name ≥1 (69% vs 81%), ≥2 (43% vs 63%), and ≥3 (19% vs 32%) warning signs of stroke. Respondents who could identify ≥2 warning signs were significantly more likely to be aware of the campaign (OR=1.88, 95% CI 1.74 to 2.04). Similar results were reported from a Swedish mass-media campaign (Nordanstig et al. 2017), whereby the number of respondents who could identify some, or all of the words in the FAST mnemonic increased significantly from 4% before the campaign, to 23% during and immediately after, although decreasing to 14%, 21 months after the campaign ended. Jurkowski et al. (2010) reported that following a public awareness campaign to increase awareness of FAST, respondents who were exposed to a 3-phase multimedia campaign over a 7-month period were more likely to be aware of the campaign and its primary message to call 9-1-1. From pre- to post-campaign, the percentage of respondents who reported they would call 9-1-1 in response to specific stroke symptoms increased from 9%-12% for specific symptoms identified in oneself and 4%-12% for specific symptoms identified in others, compared to those who had not been exposed to the campaign.
Rasura et al. (2014) conducted a review of 22 studies, of which 14 targeted the general public using mass media campaigns. The duration of these campaigns varied from 3 months to 4 years. Three popular stroke signs and symptoms were included in all of the studies using mass media campaigns: FAST, SUDDEN and Give-Me-Five. Effectiveness of the interventions was assessed in most studies through questionnaires administered pre-and post-intervention. The authors concluded that large public health campaigns using mass media are expensive and short lived and may not be effective, although the increased costs could be mitigated through more prompt treatment with t-PA. They also indicated that, to be effective, the message being delivered must direct the person to call an ambulance. They also reported that the dose of the campaign appeared to be as important as the message. Television was found to be the most effective medium. While online campaigns can also be successful, the authors reported that they tend to attract a self-selected group (e.g. well-educated women).
Mass media campaigns have also been shown to be associated with increases in the use of thrombolytic agents following acute stroke. Advani et al. (2016) reported that the average number of patients treated with t-PA increased significantly from 7.3 to 11.3 patients per month (an increase of 54.7%, p=0.02) in the 6-month period following the introduction of a mass media intervention that featured the FAST mnemonic, compared to the preceding 12 month-period. The average number of patients treated in the ER increased significantly from 37.3 to 72.8 patients per month (an increase of 95.7%, p<0.001) during the same period. Although the mean number of patients treated with t-PA dropped to 9.5 per month after the first 6 months of the campaign, it was still significantly higher than the preceding 12 months. In a telephone survey including 1,400 participants, the number of people who could name any stroke symptom increased from 66% to 75%. Of those who could name a symptom, 52% recognized facial droop, 42% named speech difficulties and 42% named arm weakness.