Clinical outcomes among stroke patients receiving tissue plasminogen activator therapy beyond the 3-hour time window.

BACKGROUND: Tissue plasminogen activator therapy (t-PA) is associated with improved neurologic outcomes and reduced disability from ischemic stroke. The current guidelines stipulate that patients receive t-PA within 3 hours of symptom onset. However, actual practice patterns vary, and little is known about patient outcomes when t-PA is received outside of the recommended time window. METHODS: We examined mean length of hospital stay, t-PA-related complications, and in-hospital death by time of t-PA administration in North Carolina Stroke Care Collaborative (NCSCC) patients. The NCSCC includes 53 hospitals that enroll patients presenting with stroke-like symptoms. Of 40,907 patients enrolled between January 2005 and February 2010, 1070 (2.6%) received t-PA. Of these, 88.2% received t-PA within 3 hours of symptom onset ("early") and 30.3% received t-PA between 3 and 6 hours after symptom onset ("late"). RESULTS: Unadjusted mean length of stay (days) was longer among early patients (5.0 days; 95% confidence interval [CI], 4.7-5.3) than late patients (3.6 days; 95% CI, 3.1-4.2). t-PA-related complications were similar among early (7.0%; 55/781) and late patients (6.7%; 7/102; P = .89). The proportion of in-hospital deaths was similar among late (10.5%) and early patients (12.0%). We used multivariable logistic regression to estimate odds ratios (ORs) and 95% CIs for the associations between late t-PA status and patient outcomes. CONCLUSIONS: In models controlling for age, race, sex, arrival mode, and ambulatory status on admission, late t-PA was not associated with increased odds of complications or in-hospital deaths (OR, 0.89; 95% CI, 0.49-1.62). The risks and benefits of expansion of the t-PA time window in stroke patients merit further investigation.

A multicenter evaluation of the ABCD2 score's accuracy for predicting early ischemic stroke in admitted patients with transient ischemic attack.

STUDY OBJECTIVE: We evaluate, in admitted patients with transient ischemic attack, the accuracy of the ABCD(2) (age [A], blood pressure [B], clinical features [weakness/speech disturbance] [C], transient ischemic attack duration [D], and diabetes history [D]) score in predicting ischemic stroke within 7 days. METHODS: At 16 North Carolina hospitals, we enrolled a prospective, nonconsecutive sample of admitted patients with transient ischemic attack and with no stroke history, presenting within 24 hours of transient ischemic attack symptom onset. We conducted a medical record review to determine ischemic stroke outcomes within 7 days. According to a modified Rankin Scale Score, strokes were classified as disabling (>2) or nondisabling (< or =2). RESULTS: During a 35-month period, we enrolled 1,667 patients, of whom 373 (23%) received a diagnosis of an ischemic stroke within 7 days. Eighteen percent (69/373) of all strokes were disabling. We were unable to calculate an ABCD(2) score in 613 patients (37%); however, our imputed analysis indicated this did not significantly alter results. The discriminatory power of the ABCD(2) score was modest for ischemic stroke in 7 days (c statistic 0.59), and fair for disabling ischemic stroke within 7 days (c statistic 0.71). Patients characterized as low risk according to ABCD(2) score (< or =3) were at low risk for experiencing a disabling stroke within 7 days, with a negative likelihood ratio of 0.16 (95% confidence interval [CI] 0.04 to 0.64) with missing values excluded and 0.34 (95% CI 0.15 to 0.76) when missing values were imputed. CONCLUSION: Our analysis suggests the best application of the ABCD(2) score may be to identify patients at low risk for an early disabling ischemic stroke. Further study of the ability to determine an ABCD(2) score in all patients is needed, along with validation in a large, consecutive population of patients with transient ischemic attack.

Early diffusion weighted MRI as a negative predictor for disabling stroke after ABCD2 score risk categorization in transient ischemic attack patients.

BACKGROUND AND PURPOSE: The prognostic value early diffusion-weighted magnetic resonance imaging (DWMRI) adds in the setting of transient ischemic attack (TIA), after risk stratification by a clinical score, is unclear. The purpose of this study is to evaluate, after ABCD2 score risk categorization in admitted TIA patients, whether negative DWMRI performed within 24 hours of symptom onset improves on the identification of patients at low risk for experiencing a disabling stroke within 90 days. METHODS: At 15 North Carolina hospitals, we enrolled a prospective nonconsecutive sample of admitted TIA patients. We excluded patients not undergoing a DWMRI within 24 hours of admission and patients for whom a dichotomized (< or = or >3) ABCD2 score could not be calculated. We conducted a medical record review to determine disabling ischemic stroke outcomes within 90 days. RESULTS: Over 35 months, 944 TIA patients met inclusion criteria, of whom 4% (n=41) had a disabling ischemic stroke within 90 days. In analyses stratified by low versus moderate/high ABCD2 score, the combination of a low risk ABCD2 score and a negative early DWMRI had excellent sensitivity (100%, 95% CI 34 to 100) for identifying low-risk patients. In patients classified as moderate to high risk, a negative early DWMRI predicted a low risk of disabling ischemic stroke within 90 days (sensitivity 92%, 95% CI 80 to 97; NLR 0.11, 95% CI 0.04 to 0.32). CONCLUSIONS: After risk stratification by the ABCD2 score, early DWMRI enhances the prediction of a low risk for disabling ischemic stroke within 90 days. Further study is warranted in a large, consecutive TIA population of early DWMRI as a sensitive negative predictor for disabling stroke within 90 days.

Predictors of time from hospital arrival to initial brain-imaging among suspected stroke patients: the North Carolina Collaborative Stroke Registry.

BACKGROUND AND PURPOSE: We examined patient demographic and hospital characteristics and clinical predictors of delay time from hospital arrival until CT among 20 374 patients enrolled in the North Carolina Collaborative Stroke Registry (January 2005 to April 2008). METHODS: Delay time was log-transformed in linear regression analyses and dichotomized (25 minutes) in logistic regression analyses to correspond to a 1999 National Institute of Neurological Disorders and Stroke guideline. RESULTS: In multiple linear regression analyses, prehospital delay time, mode of transport, race, gender, presumptive diagnosis, time of day of arrival, weekday versus weekend arrival, and hospital type (defined by Joint Commission Primary Stroke Center certification and teaching status) were significantly associated with CT delay. In analyses of 3549 patients arriving within 2 hours of symptom onset, time of day of arrival and weekday versus weekend arrival were no longer significant. Among patients arriving within 2 hours of symptom onset, the strongest independent predictors of meeting the National Institute of Neurological Disorders and Stroke (NINDS) guideline were arrival by emergency medical services versus other modes of transportation (odds ratio, 95% CI=2.3 [1.9, 2.8]) and a presumptive diagnosis of transient ischemic attack versus unspecified stroke type (odds ratio, 95% CI=0.4 [0.3, 0.5]). CONCLUSIONS: Most patients do not arrive to the hospital in a timely manner and cannot be considered for time-dependent therapies. Among those that do, disparities exist in time to receipt of CT scan, suggesting room for improvement in hospital-level stroke systems of care.