Introduction
It is estimated that 15 million people suffer from stroke,
resulting in 5.5 million deaths worldwide annually,1 and
significant disability-adjusted life-years lost.2,3 Intravenous
thrombolytic therapy has been proved to benefit patients
with acute ischemic stroke (IS) and recommended on current
guidelines of acute stroke management.4,5 However, it
can only be administered in patients whose stroke onset
within a very short time window of presentation,4e6 and
thus many patients are excluded from thrombolytic therapy,
mainly related to prehospital delay.7 In addition, it has
been shown that the sooner thrombolytic therapy is given
to stroke patients, the better the functional outcome.8e10
Thus, efforts are needed not only to increase the number
of stroke patients receiving thrombolytic therapy, but also
to shorten the time interval between stroke onset and
starting thrombolytic therapy (onset-to-needle time).
Several studies have shown that stroke patients utilizing
emergency medical services (EMS) can arrive in the emergency
department (ED) earlier than those who do not.11e16
Therefore, cooperation between EMS and hospitals may
shorten in-hospital management time in acute IS patients.17,18
However, whether utilization of EMS further
increases the chance that patients will arrive within the
therapeutic time window for thrombolytic administration
has not been determined. In this study, we investigated
whether IS patients who presented to the ED by EMS more
frequently arrived within 3 hours of stroke onset, were
more likely to receive thrombolytic therapy, and had
shorter onset-to-needle time than those did not use EMS.