BMJ Open. 2026 Sep 18;16(9):e119656. doi: 10.1136/bmjopen-2026-119656.
ABSTRACT
OBJECTIVES: To investigate the association between the time of day of stroke onset and functional outcomes among patients with acute ischaemic stroke who received reperfusion therapy.
DESIGN: Retrospective cohort study.
SETTING: Patients with acute ischaemic stroke who received reperfusion therapy (intravenous thrombolysis or combined endovascular therapy) between October 2018 and March 2022 in China were included.
PARTICIPANTS: A total of 712 patients with acute ischaemic stroke receiving reperfusion therapy were included. Patients were categorised into two groups (day-onset (06:00-18:00) and night-onset (18:00-06:00)) and into six groups by 4-hour intervals.
OUTCOME MEASURES: The primary outcome was the 3-month functional status, evaluated using the modified Rankin Scale, with scores of 0-2 classified as favourable and scores of 3-6 as unfavourable outcomes. Propensity score matching (PSM), inverse probability of treatment weighting (IPTW) and overlap weighting (OW) were used for analyses.
RESULTS: 148 out of 286 patients (51.7%) in the night-onset group and 182 out of 426 patients (42.7%) in the day-onset group experienced unfavourable outcomes at 3 months. Night-onset stroke was associated with a significantly higher risk of unfavourable outcome compared with day-onset stroke (OR 1.44 (95% CI 1.06 to 1.94), p=0.018). This association remained significant after adjustment using PSM (OR 1.45 (95% CI 1.01 to 2.08), p=0.044), and was further confirmed in analyses using IPTW (OR 1.42 (95% CI 1.02 to 1.96), p=0.036), OW (OR 1.42 (95% CI 1.03 to 1.96), p=0.032) and multivariable adjustment (adjusted OR 1.55 (95% CI 1.07 to 2.22), p=0.019). Night-onset stroke during 22:00-02:00 (adjusted OR 2.44 (95% CI 1.34 to 4.43), p=0.003) was significantly associated with a higher likelihood of unfavourable outcome in adjusted analysis.
CONCLUSIONS: Night-onset stroke was associated with poorer functional outcomes at 3 months among patients receiving reperfusion therapy. Further multicentre prospective studies are warranted to validate these findings.
TRIAL REGISTRATION NUMBER: Chinese Clinical Trial Registry Identifier: ChiCTR2500101844.
PMID:42760078 | DOI:10.1136/bmjopen-2026-119656