To investigate the impact of setting door-to-needle time (DNT) 60 min as a quality-control benchmark on 90-day post-thrombolytic therapy prognosis and length of hospital stay (LOS) in patients with acute ischemic stroke (AIS) treated with intravenous thrombolysis using alteplase or urokinase.

This study prospectively enrolled AIS patients receiving intravenous thrombolysis with alteplase or urokinase at Baotou Central Hospital from January 2020 to January 2023. The patients were divided into the target group (DNT ≤60 min) and the delay group (DNT ＞60 min) according to DNT. They were further stratified into the alteplase subgroup and the urokinase subgroup. The patients were classified into the favorable-prognosis group [modified Rankin scale (mRS) score ＜3] and the poor-prognosis group (mRS score ≥3) based on the 90-day post-thrombolysis mRS score. The χ² test or Fisher's exact test was used to compare the hemorrhagic transformation rate, in-hospital all-cause mortality and 90-day poor-prognosis rate among groups. Multivariable Logistic regression was performed only in the alteplase subgroup to identify independent influencing factors for 90-day poor prognosis. Multivariable linear regression was applied to analyze the association between DNT and LOS.

In the overall cohort, there were 92 patients in the target group and 219 patients in the delay group. Within the alteplase subgroup, there were 58 patients in the target group and 163 patients in the delay group; within the urokinase subgroup, there were 34 patients in the target group and 56 patients in the delay group. In the overall cohort, there were no significant differences between the target group and the delay group in hemorrhagic transformation rate [3.26% (3/92) vs 6.39% (14/219), χ²=1.230, P=0.267] and in-hospital all-cause mortality [2.17% (2/92) vs 3.20% (7/219), P＞0.999]. After excluding 16 patients lost to follow-up for 90-day outcome assessment, the 90-day poor-prognosis rate was 19.54% (17/87) in the target group and 22.60% (47/208) in the delay group without significant difference (χ²=0.337, P=0.561). Within the alteplase subgroup, the 90-day poor-prognosis rate of the target group was 11.11% (6/54), which was significantly lower than 23.87% (37/155) of the delay group (χ²=3.990, P=0.046). No significant inter-group differences in hemorrhagic transformation rate, in-hospital all-cause mortality and 90-day poor-prognosis rate were found in the urokinase subgroup (all P＞0.05). After adjusting for confounders including baseline NIHSS score, atrial fibrillation, gender, age, smoking history and hemorrhagic transformation in the alteplase subgroup, stratification by the DNT cutoff of 60 min was not an independent protective factor against 90-day poor prognosis (OR=1.223, 95%CI: 0.378–3.955, P=0.737). However, when DNT was analyzed as a continuous variable, the odds of 90-day poor prognosis increased with longer DNT; each additional 1-minute delay in DNT was associated with a 1.2% increment in the odds of poor prognosis (OR=1.012, 95%CI: 1.000–1.023, P=0.049). Multivariable linear regression showed an independent positive correlation between DNT and LOS (β=0.428, P＜0.001).

Among the overall AIS patients undergoing intravenous thrombolysis, using DNT ≤60 min as the quality-control benchmark, no improvement in the prognosis was observed in AIS patients at 90-day post intravenous thrombolysis. Among patients treated with alteplase, DNT as a continuous variable showed a time-dependent association with poor prognosis.