Fonarow GC, Smith EE, Saver JL, Reeves MJ, Bhatt DL, Grau-Sepulveda MV, Olson DM, Hernandez AF, Peterson ED, Schwamm LH. Circulation. 2011 Feb 22;123(7):750-8.
Real-world retrospective, multi-center analysis
This retrospective, multi-center study analyzed data from the Get With the Guidelines-Stroke (CWTG-Stroke) national registry of acute ischemic stroke patients who were treated with intravenous tissue-type plasminogen activator (tPA) within 3 hours of symptom onset from April 1, 2003 to September 30, 2009. National guidelines recommend that hospitals complete the clinical and imaging evaluation of acute ischemic stroke patients and initiate intravenous tPA therapy within 60 minutes of patient arrival. This study aimed to determine the presenting characteristics of acute ischemic stroke patients treated with tPA who had door-to-needle times of <60 minutes, patient and hospital characteristics associated with door-to-needle treatment times of <60 minutes, in-hospital clinical outcomes of tPA treatment in <60 minutes, and temporal trends in timely thrombolytic care.
The GWTG-Stroke database included 595,172 acute ischemic stroke admissions submitted by 1,259 hospitals between April 1, 2003 and September 30, 2009. This study used only patients who were treated with intravenous tPA within 3 hours of symptom onset, resulting in 25,504 (19.7%) patients from 1,082 hospitals. Patient data included demographics, medical history, onset time of stroke symptoms, arrival time, in-hospital diagnostic studies, treatments and procedures, discharge treatments and counseling, tPA treatment initiation time, tPA complications, in-hospital mortality, discharge destination, and stroke severity.
The analysis compared patient demographic and clinical variables, hospital level characteristics, and clinical outcomes between patients with and without door-to-needle time of <60 minutes. These relationships were further examined with multivariable logistic regression models. The study used generalized estimation equations (GEEs) to generate unadjusted and adjusted models and to determine significant confounders, including but not limited to age, race, sex, stroke severity, onset-to-arrival time, and average number of patients treated with tPA annually at each hospital. Additionally, the study used GEE models to analyze the relationship between door-to-needle time and tPA complications and the long-term temporal trends in door-to-needle time of <60 minutes.
Among the 25,504 ischemic stroke patients treated with tPA, door-to-needle time was <60 minutes in only 6,790 (26.6%) patients. The mean door-to-needle time for intravenous tPA administration was 79.3±28.1 minutes. Patient factors most strongly associated with door-to-needle time of <60 minutes were younger age, male gender, white race, no prior stroke, greater time since symptom onset, and arrival during on-hours (Monday through Friday, 7 AM to 5 PM) and by emergency medical service transport.
Hospital characteristics associated with <60-minute door-to-needle time included greater number of patients treated with intravenous tPA annually and lower annual number of stroke admissions. The proportion of patients with door-to-needle times of <60 minutes varied widely by hospital (0% to 79.2%) and increased by approximately 1.6% per year from 19.5% in 2003 to 29.1% in 2009 (P<0.0001). Despite similar stroke severity, in-hospital mortality was lower and symptomatic intracranial hemorrhage was less frequent for patients with door-to-needle times of <60 minutes compared with patients with door-to-needle times of >60 minutes.
The authors acknowledged some limitations of this analysis. Lower mortality had not previously been reported with timelier tPA therapy, so the authors urged replication of their analysis. The hospitals in this study were self-selected, so it is likely that other U.S. hospitals would have a smaller portion of patients with door-to-needle time of <60 minutes than those in this study. Some additional factors that may be important for timely treatment with tPA were not captured or analyzed in this study, including prehospital notification by emergency medical service, existence of a regional stroke system of care with routing of stroke patients directly to designated stroke centers, and availability of stroke neurologists. Finally, no information was collected on post-discharge stroke-related outcomes in the GWTG-Stroke Program. Therefore, whether door-to-needle times of within 60 minutes have longer term impacts on functional outcomes was not able to be ascertained.
The study concluded that older patients, non-white patients, women, and those with less severe strokes or arriving during off-hours were less likely to receive timely treatment. Additionally, hospitals with less experience in providing tPA to ischemic stroke patients were less likely to provide thrombolytic therapy within 60 minutes. The authors argued that their findings support the need for a targeted initiative to improve the timeliness of reperfusion in acute ischemic stroke. They suggested that aspects of the GWTG-Stroke toolkit, intervention strategies, and recognition system be updated to highlight the importance of the <60-minute door-to-needle target.
Table 3 from the paper summarizes how patient and hospital characteristics were associated with door-to-needle time of <60 minutes.
The authors concluded that:
Tables recreated from original article
The table reflects multivariable modeling performed with 20,358 patients with full data available, including NIHSS. No major differences (apart from NIHSS) were observed when the model was constructed using the more complete cohort of patients (n=24,385) without recorded NIHSS. The findings were also similar when hospital characteristics of annual ischemic stroke admissions and annual tPA patients treated were analyzed as continuous variables and interaction terms were included in the model.
Teleflex did not sponsor, pay for, or independently verify the results of the work summarized herein and therefore is not responsible for the methodology utilized or the results obtained. Teleflex has made all efforts to summarize the work accurately but cannot guarantee the accuracy or completeness of the summary as it is based on the original paper. In the event an inaccuracy arises, please inform Teleflex so that it can be corrected.
Teleflex and the Teleflex logo are trademarks or registered trademarks of Teleflex Incorporated or its affiliates, in the U.S. and/or other countries. All rights reserved. © 2023 Teleflex Incorporated. MC-008418 (02/2023)