Temporal trends in patient characteristics and treatment with intravenous thrombolysis among acute ischemic stroke patients at Get With The Guidelines-Stroke hospitals

Abstract

Background: Substantial efforts over the past decade have increased rates of intravenous tissue plasminogen activator (tPA) use in the United States. We sought to determine changes in patient characteristics and rates of tPA use over time among hospitalized acute ischemic stroke (AIS) patients.

Methods and results: We analyzed all AIS patients (n=1 093 895) and those arriving ≤ 2 hours and treated with tPA ≤ 3 hours after onset (n=50 798) from 2003 to 2011 in the American Heart Association's Get with the Guideline-Stroke (GWTG-Stroke). Categorical data were analyzed by Pearson χ(2) and continuous data by Wilcoxon test. Intravenous tPA use ≤ 3 hours after onset increased from 4.0% to 7.0% in all AIS admissions and 42.6% to 77.0% in AIS patients arriving ≤ 2 hours and fully eligible for tPA (P<0.001). In univariate analysis, tPA use increased over time, especially in those aged >85 years, nonwhite, and with milder strokes (National Institutes of Health Stroke Scale 0-4). Door-to-image time (median 24 versus 20 minutes) and door-to-tPA time (median 81 versus 72 minutes) also improved, with ≈65% of tPA-treated patients getting brain imaging ≤ 25 minutes after arrival. Multivariable analysis showed that with each additional calendar year, the odds that an eligible patient would receive tPA increased by 1.37-fold, adjusting for other covariates.

Conclusions: The frequency of IV tPA use among all AIS patients, regardless of contraindications, nearly doubled from 2003 to 2011. Treatment with tPA has expanded to include more patients with mild deficits, nonwhite race/ethnicity, and oldest old age.

Keywords: cerebrovascular disorders; ischemic attack, transient; thrombolysis, therapeutic.