The California, ABCD, and ABCD2 risk scores (ABCD system) were developed to help stratify short-term stroke risk in patients with TIA (transient ischemic attack). Beyond this scope, the ABCD system has been extensively used to study other prognostic information such as DWI (diffusion-weighted imaging) abnormalities, large artery stenosis, atrial fibrillation and its diagnostic accuracy in TIA patients, which are independent predictors of subsequent stroke in TIA patients. Our comprehensive paper suggested that all scores have and equivalent prognostic value in predicting short-term risk of stroke; however, the ABCD2 score is being predominantly used at most centers. The majority of studies have shown that more than half of the strokes in the first 90 days, occur in the first 7 days. The majority of patients studied were predominantly classified to have a higher ABCD/ABCD2 > 3 scores and were particularly at a higher short-term risk of stroke or TIA and other vascular events. However, patients with low risk ABCD2 score < 4 may have high-risk prognostic indicators, such as diffusion weighted imaging (DWI) abnormalities, large artery atherosclerosis (LAA), and atrial fibrillation (AF). The prognostic value of these scores improved if used in conjunction with clinical information, vascular imaging data, and brain imaging data. Before more data become available, the diagnostic value of these scores, its applicability in triaging patients, and its use in evaluating long-term prognosis are rather secondary; thus, indicating that the primary significance of these scores is for short-term prognostic purposes. 1. Introduction Annually, approximately 240,000 TIAs are diagnosed in the United States [1]. TIAs admissions represent approximately 0.3% of ED (Emergency Department) visits [2], and about 23% of strokes are preceded by a history of TIA [3]. Recent studies have suggested that early care and rapid ED initiated treatment and diagnostic protocols within 24 hours can reduce post-TIA stroke rates significantly [4–6]. The short-term risk of stroke after a TIA is substantially higher than previously thought and significantly higher than the short-term risk of recurrent stroke. After a stroke, the 30-day risk of stroke is estimated to be 1.5% (CI 0.6–2.5), [7], whereas the risk of stroke following TIA was 3.1% (95% CI 2.0–4.1) after 2 days and 5.2% (3.9–6.5) after 7 days [8]. Over recent years, three clinical prediction rules (ABCD, California, and ABCD2) (Table 1) have been developed with a purpose of predicting short-term risk of stroke [9, 10]. Although,
References
[1]
D. Kleindorfer, M. D. Hill, D. Woo et al., “A description of Canadian and United States physician reimbursement for thrombolytic therapy administration in acute ischemic stroke,” Stroke, vol. 36, no. 3, pp. 682–687, 2005.
[2]
J. A. Edlow, S. Kim, A. J. Pelletier, and C. A. Camargo, “National study on emergency department visits for transient ischemic attack, 1992–2001,” Academic Emergency Medicine, vol. 13, no. 6, pp. 666–672, 2006.
[3]
P. M. Rothwell and C. P. Warlow, “Timing of TIAs preceding stroke: time window for prevention is very short,” Neurology, vol. 64, no. 5, pp. 817–820, 2005.
[4]
J. Kennedy, M. D. Hill, K. J. Ryckborst, M. Eliasziw, A. M. Demchuk, and A. M. Buchan, “Fast assessment of stroke and transient ischaemic attack to prevent early recurrence (FASTER): a randomised controlled pilot trial,” Lancet Neurology, vol. 6, no. 11, pp. 961–969, 2007.
[5]
P. C. Lavallée, E. Meseguer, H. Abboud et al., “A transient ischaemic attack clinic with round-the-clock access (SOS-TIA): feasibility and effects,” Lancet Neurology, vol. 6, no. 11, pp. 953–960, 2007.
[6]
P. M. Rothwell, M. F. Giles, A. Chandratheva et al., “Effect of urgent treatment of transient ischaemic attack and minor stroke on early recurrent stroke (EXPRESS study): a prospective population-based sequential comparison,” Lancet, vol. 370, no. 9596, pp. 1432–1442, 2007.
[7]
M. S. Dhamoon, R. R. Sciacca, T. Rundek, R. L. Sacco, and M. S. V. Elkind, “Recurrent stroke and cardiac risks after first ischemic stroke: the Northern Manhattan Study,” Neurology, vol. 66, no. 5, pp. 641–646, 2006.
[8]
M. F. Giles and P. M. Rothwell, “Risk of stroke early after transient ischaemic attack: a systematic review and meta-analysis,” Lancet Neurology, vol. 6, no. 12, pp. 1063–1072, 2007.
[9]
S. C. Johnston, D. R. Gress, W. S. Browner, and S. Sidney, “Short-term prognosis after emergency department diagnosis of TIA,” Journal of the American Medical Association, vol. 284, no. 22, pp. 2901–2906, 2000.
[10]
P. M. Rothwell, M. F. Giles, E. Flossmann et al., “A simple score (ABCD) to identify individuals at high early risk of stroke after transient ischaemic attack,” Lancet, vol. 366, no. 9479, pp. 29–36, 2005.
[11]
S. A. Josephson, S. Sidney, T. N. Pham, A. L. Bernstein, and S. C. Johnston, “Higher ABCD score predicts patients most likely to have true transient ischemic attack,” Stroke, vol. 39, no. 11, pp. 3096–3098, 2008.
[12]
T. J. Quinn, A. C. Cameron, J. Dawson, K. R. Lees, and M. R. Walters, “ABCD2 scores and prediction of noncerebrovascular diagnoses in an outpatient population: a case-control study,” Stroke, vol. 40, no. 3, pp. 749–753, 2009.
[13]
J. N. E. Redgrave, S. B. Coutts, U. G. Schulz, D. Briley, and P. M. Rothwell, “Systematic review of associations between the presence of acute ischemic lesions on diffusion-weighted imaging and clinical predictors of early stroke risk after transient ischemic attack,” Stroke, vol. 38, no. 5, pp. 1482–1488, 2007.
[14]
J. K. Lovett, A. J. Coull, and P. M. Rothwell, “Early risk of recurrence by subtype of ischemic stroke in population-based incidence studies,” Neurology, vol. 62, no. 4, pp. 569–573, 2004.
[15]
R. G. Hart, O. Benavente, R. McBride, and L. A. Pearce, “Antithrombotic therapy to prevent stroke in patients with atrial fibrillation: a meta-analysis,” Annals of Internal Medicine, vol. 131, no. 7, pp. 492–501, 1999.
[16]
S. C. Johnston, P. M. Rothwell, M. N. Nguyen-Huynh et al., “Validation and refinement of scores to predict very early stroke risk after transient ischaemic attack,” Lancet, vol. 369, no. 9558, pp. 283–292, 2007.
[17]
S. C. Johnston, S. Sidney, A. L. Bernstein, and D. R. Gress, “A comparison of risk factors for recurrent TIA and stroke in patients diagnosed with TIA,” Neurology, vol. 60, no. 2, pp. 280–285, 2003.
[18]
B. L. Cucchiara, S. R. Messe, R. A. Taylor et al., “Is the ABCD score useful for risk stratification of patients with acute transient ischemic attack?” Stroke, vol. 37, no. 7, pp. 1710–1714, 2006.
[19]
F. Purroy, C. A. Molina, J. Montaner, and J. álvarez-Sabín, “Absence of usefulness of ABCD score in the early risk of stroke of transient ischemic attack patients,” Stroke, vol. 38, no. 3, pp. 855–856, 2007.
[20]
R. Sciolla and F. Melis, “Rapid identification of high-risk transient ischemic attacks: prospective validation of the ABCD score,” Stroke, vol. 39, no. 2, pp. 297–302, 2008.
[21]
G. Tsivgoulis, K. Spengos, P. Manta et al., “Validation of the ABCD score in identifying individuals at high early risk of stroke after a transient ischemic attack: a hospital-based case series study,” Stroke, vol. 37, no. 12, pp. 2892–2897, 2006.
[22]
J. Bray, C. Bladin, K. Coughlan, and A. Patil, “Lessons learnt in implementation of ABCD score in an emergency department,” Stroke, vol. 39, no. 7, p. e111, 2008.
[23]
A. Fothergill, T. J. H. Christianson, R. D. Brown, and A. A. Rabinstein, “Validation and refinement of the ABCD2 score: a population-based analysis,” Stroke, vol. 40, no. 8, pp. 2669–2673, 2009.
[24]
D. Calvet, C. Lamy, E. Touzé, C. Oppenheim, J. F. Meder, and J. L. Mas, “Management and outcome of patients with transient ischemic attack admitted to a stroke unit,” Cerebrovascular Diseases, vol. 24, no. 1, pp. 80–85, 2007.
[25]
A. W. Asimos, W. D. Rosamond, A. M. Johnson et al., “Early diffusion weighted MRI as a negative predictor for disabling stroke after ABCD2 score risk categorization in transient ischemic attack patients,” Stroke, vol. 40, no. 10, pp. 3252–3257, 2009.
[26]
A. W. Asimos, A. M. Johnson, W. D. Rosamond et al., “A multicenter evaluation of the ABCD2 score's accuracy for predicting early ischemic stroke in admitted patients with transient ischemic attack,” Annals of Emergency Medicine, vol. 55, no. 2, pp. 201–210, 2010.
[27]
A. W. Asimos, H. J. Norton, M. F. Price, and W. M. Cheek, “Therapeutic yield and outcomes of a community teaching hospital code stroke protocol,” Academic Emergency Medicine, vol. 11, no. 4, pp. 361–370, 2004.
[28]
B. C. K. Choi, “Slopes of a receiver operating characteristic curve and likelihood ratios for a diagnostic test,” American Journal of Epidemiology, vol. 148, no. 11, pp. 1127–1132, 1998.
[29]
J. A. Hanley, “The place of statistical methods in radiology (and in the bigger picture),” Investigative Radiology, vol. 24, no. 1, pp. 10–16, 1989.
[30]
S. C. Johnston, P. M. Rothwell, M. N. Nguyen-Huynh, et al., “The ABCD, California, and unified ABCD2 Score Predicted stroke within 2, 7, 90 days after TIA,” Evidence-Based Medicine, vol. 12, pp. 88–89, 2007.
[31]
M. F. Giles and P. M. Rothwell, “Systematic review and meta-analysis of validations of ABCD and ABCD2 scores in prediction of stroke risk after transient ischemic attack,” Cerebrovascular Diseases, vol. 25, p. 59, 2008.
[32]
M. F. Giles and P. M. Rothwell, “Systematic review and pooled analysis of published and unpublished validations of the ABCD and ABCD2 transient ischemic attack risk scores,” Stroke, vol. 41, no. 4, pp. 667–673, 2010.
[33]
J. E. Bray, K. Coughlan, and C. Bladin, “Can the ABCD Score be dichotomised to identify high-risk patients with transient ischaemic attack in the emergency department?” Emergency Medicine Journal, vol. 24, no. 2, pp. 92–95, 2007.
[34]
F. Purroy, J. Montaner, C. A. Molina, P. Delgado, M. Ribo, and J. álvarez-Sabín, “Patterns and predictors of early risk of recurrence after transient ischemic attack with respect to etiologic subtypes,” Stroke, vol. 38, no. 12, pp. 3225–3229, 2007.
[35]
S. Koton and P. M. Rothwell, “Performance of the ABCD and ABCD2 scores in TIA patients with carotid stenosis and atrial fibrillation,” Cerebrovascular Diseases, vol. 24, no. 2-3, pp. 231–235, 2007.
[36]
L. G. Stead, S. Suravaram, M. Bellolio, et al., “Performance of the ABCD2 score in an emergency department population presenting with transient ischemic attack: a prospective observational study,” Annals of Emergency Medicine, vol. 52, pp. S162–S163, 2008.
[37]
K. C. Johnston, D. P. Wagner, X. Q. Wang et al., “Validation of an acute ischemic stroke model: does diffusion-weighted imaging lesion volume offer a clinically significant improvement in prediction of outcome?” Stroke, vol. 38, no. 6, pp. 1820–1825, 2007.
[38]
B. L. Cucchiara, S. R. Messe, L. Sansing et al., “D-dimer, magnetic resonance imaging diffusion-weighted imaging, and ABCD2 score for transient ischemic attack risk stratification,” Journal of Stroke and Cerebrovascular Diseases, vol. 18, no. 5, pp. 367–373, 2009.
[39]
M. Mlynash, J. M. Olivot, D. C. Tong et al., “Yield of combined perfusion and diffusion MR imaging in hemispheric TIA,” Neurology, vol. 72, no. 13, pp. 1127–1133, 2009.
[40]
H. Ay, E. M. Arsava, S. C. Johnston et al., “Clinical- and imaging-based prediction of stroke risk after transient ischemic attack: the CIP model,” Stroke, vol. 40, no. 1, pp. 181–186, 2009.
[41]
S. B. Coutts, J. E. Simon, M. Eliasziw et al., “Triaging transient ischemic attack and minor stroke patients using acute magnetic resonance imaging,” Annals of Neurology, vol. 57, no. 6, pp. 848–854, 2005.
[42]
O. C. Sheehan, L. Kyne, L. A. Kelly et al., “Population-based study of ABCD score, carotid stenosis, and atrial fibrillation for early stroke prediction after transient ischemic attack: the North Dublin TIA study,” Stroke, vol. 41, no. 5, pp. 844–850, 2010.
[43]
D. Calvet, E. Touzé, C. Oppenheim, G. Turc, J. F. Meder, and J. L. Mas, “DWI lesions and TIA etiology improve the prediction of stroke after TIA,” Stroke, vol. 40, no. 1, pp. 187–192, 2009.
[44]
J. N. Redgrave, U. G. Schulz, D. Briley, T. Meagher, and P. M. Rothwell, “Presence of acute ischaemic lesions on diffusion-weighted imaging is associated with clinical predictors of early risk of stroke after transient ischaemic attack,” Cerebrovascular Diseases, vol. 24, no. 1, pp. 86–90, 2007.
[45]
F. Purroy, R. Begué, A. Quílez et al., “The california, abcd, and unified abcd2 risk scores and the presence of acute ischemic lesions on diffusion-weighted imaging in tia patients,” Stroke, vol. 40, no. 6, pp. 2229–2232, 2009.
[46]
L. R. Caplan, “Transient ischemic attack with abnormal diffusion-weighted imaging results: what's in a name?” Archives of Neurology, vol. 64, no. 8, pp. 1080–1082, 2007.
[47]
P. N. Sylaja, S. B. Coutts, S. Subramaniam, M. D. Hill, M. Eliasziw, and A. M. Demchuk, “Acute ischemic lesions of varying ages predict risk of ischemic events in stroke/TIA patients,” Neurology, vol. 68, no. 6, pp. 415–419, 2007.
[48]
F. Purroy, G. Pi？ol-Ripoll, A. Quílez, J. Sanahuja, L. Brieva, and I. Suárez Luis, “Validation of the ABCDI and ABCD2I scales in the registry of patients with transient ischemic attacks from Lleida (REGITELL),” Medicina Clinica. In press.
[49]
F. Purroy, J. Montaner, A. Rovira, P. Delgado, M. Quintana, and J. álvarez-Sabín, “Higher risk of further vascular events among transient ischemic attack patients with diffusion-weighted imaging acute ischemic lesions,” Stroke, vol. 35, no. 10, pp. 2313–2319, 2004.
[50]
R. Bond, K. Rerkasem, and P. M. Rothwell, “Systematic review of the risks of carotid endarterectomy in relation to the clinical indication for and timing of surgery,” Stroke, vol. 34, no. 9, pp. 2290–2301, 2003.
[51]
P. M. Rothwell, M. Eliasziw, S. A. Gutnikov et al., “Analysis of pooled data from the randomised controlled trials of endarterectomy for symptomatic carotid stenosis,” Lancet, vol. 361, no. 9352, pp. 107–116, 2003.
[52]
P. M. Rothwell, M. Eliasziw, S. A. Gutnikov, C. P. Warlow, and H. J. M. Barnett, “Endarterectomy for symptomatic carotid stenosis in relation to clinical subgroups and timing of surgery,” Lancet, vol. 363, no. 9413, pp. 915–924, 2004.
[53]
M. Eliasziw, J. Kennedy, M. D. Hill, A. M. Buchan, and H. J. M. Barnett, “Early risk of stroke after a transient ischemic attack in patients with internal carotid artery disease,” Canadian Medical Association Journal, vol. 170, no. 7, pp. 1105–1109, 2004.
[54]
F. Purroy, J. Montaner, P. Delgado et al., “Usefulness of urgent combined carotid/transcranial ultrasound testing in early prognosis of TIA patients,” Medicina Clinica, vol. 126, no. 17, pp. 647–650, 2006.
[55]
E. Meseguer, P. C. Lavallée, M. Mazighi et al., “Yield of systematic transcranial doppler in patients with transient ischemic attack,” Annals of Neurology, vol. 68, no. 1, pp. 9–17, 2010.
[56]
J. W. Schrock, A. Victor, and T. Losey, “Can the ABCD risk score predict positive diagnostic testing for emergency department patients admitted for transient ischemic attack?” Stroke, vol. 40, no. 10, pp. 3202–3205, 2009.
[57]
P. Amarenco, J. Labreuche, P. C. Lavallée et al., “Does ABCD2 score below 4 allow more time to evaluate patients with a transient ischemic attack?” Stroke, vol. 40, no. 9, pp. 3091–3095, 2009.
[58]
P. A. Wolf, R. D. Abbott, and W. B. Kannel, “Atrial fibrillation as an independent risk factor for stroke: the Framingham Study,” Stroke, vol. 22, no. 8, pp. 983–988, 1991.
[59]
G. Ray, F. Wright, D. J. Stott, and P. Langhorne, “A prospective study using the ABCD2 score in screening for minor stroke or transient ischaemic attack in referrals to a fast track clinic,” Stroke, vol. 40, no. 6, p. e467, 2009.
[60]
C. Wolford and O. J. Albers Greg, “Successful use of ABCD/ABCD2 scores to Triage TIA patients to an outpatient clinic,” Stroke, vol. 40, no. 4, p. 32, 2009.
[61]
E. Flo？mann and P. M. Rothwell, “Prognosis of vertebrobasilar transient ischaemic attack and minor stroke,” Brain, vol. 126, no. 9, pp. 1940–1954, 2003.
[62]
G. J. Hankey, J. M. Slattery, and C. P. Warlow, “The prognosis of hospital-referred transient ischaemic attacks,” Journal of Neurology Neurosurgery and Psychiatry, vol. 54, no. 9, pp. 793–802, 1991.
[63]
J. D. Easton, J. L. Saver, G. W. Albers et al., “Definition and evaluation of transient ischemic attack: a scientific statement for healthcare professionals from the American heart association/American stroke association stroke council; council on cardiovascular surgery and anesthesia; council on cardiovascular radiology and intervention; council on cardiovascular nursing; and the interdisciplinary council on peripheral vascular disease,” Stroke, vol. 40, no. 6, pp. 2276–2293, 2009.
[64]
J. Ferrari, M. Knoflach, S. Kiechl et al., “Early clinical worsening in patients with TIA or minor stroke: the Austrian stroke unit registry,” Neurology, vol. 74, no. 2, pp. 136–141, 2010.
[65]
M. N. Nguyen-Huynh and S. C. Johnston, “Is hospitalization after TIA cost-effective on the basis of treatment with tPA?” Neurology, vol. 65, no. 11, pp. 1799–1801, 2005.
[66]
S. A. Josephson, S. Sidney, T. N. Pham, A. L. Bernstein, and S. C. Johnston, “Factors associated with the decision to hospitalize patients after transient ischemic attack before publication of prediction rules,” Stroke, vol. 39, no. 2, pp. 411–413, 2008.
[67]
A. S. Min Lou, J. Edlow, L. Caplan, et al., “Is there an association between ABCD2 score and abnormal test results requiring in hospital interventions in patients with transient neurological deficits,” Stroke, vol. 44, 2009.
[68]
M. Erin, P. K. Grise, and J. Broderick., “ABCD2 score predicts emergency department disposition of transient ischemic attack (TIA) patients: a population based study,” Stroke, vol. 40, p. 35, 2009.
