Introduction: Delays in door-to-needle time (DNT) for tPA administration are associated with worse outcomes after acute ischemic stroke (AIS). Studies suggest tPA is safe and effective in young adults, though the effect of age on timeliness of tPA decision making is unknown. In the young adult population, lower frequency of stroke and higher frequency of stroke mimics may lead to DNT delays. We tested the hypothesis that DNT are longer in young adults with AIS.
Methods: From 1/2009 to 3/2016, patient demographics and tPA metrics were prospectively collected on all tPA-treated patients at a large, urban academic hospital. Discharge diagnosis (including stroke mimics) and symptomatic intracranial hemorrhage (sICH) rates were collected by retrospective chart review. DNT was compared between young (age ≤ 45) and older adults (age > 45) and across four age groups: ≤45, 46-65, 66-85, and ≥86. Univariate analysis evaluated associations between DNT and baseline characteristics (age, race, sex, admission year, onset-to-arrival time, and admission NIHSS), followed by forward stepwise linear regression including variables with P<0.2 on univariate analysis.
Results: Of 560 patients treated with tPA, 63 (11%) were age ≤45 and 497 (89%) were age > 45. Mean DNT was 63 minutes in young adults compared to 50 minutes in older adults (P=0.002). Across four age groups, DNTs were longer in young adults (P=0.027, Figure). In multivariable analysis, age ≤45 (P=0.012), lower NIHSS (P=0.006), and more remote admission year (P=0.001) independently predicted longer DNT. Stroke mimics were more frequent in young adults: 32% vs 7% (P<0.001), though mean DNT remained longer in young adults after excluding mimics: 63 vs 49 min (P=0.008). sICH rate was similar in both groups: 0% vs 4.2% (p=0.10).
Conclusions: Despite established safety and efficacy of tPA in young adults, we found DNT delays in this population. Further studies are needed to confirm this finding and address age-related disparities in DNT.