RT Journal Article SR Electronic T1 Off-hour effect is not significant in endovascular treatment for anterior circulation large vessel occlusion in a multicentre registry JF Stroke and Vascular Neurology JO Stroke Vasc Neurol FD BMJ Publishing Group Ltd SP svn-2021-000949 DO 10.1136/svn-2021-000949 A1 Mingming Zha A1 Qingwen Yang A1 Shuo Liu A1 Kangmo Huang A1 Xiaohao Zhang A1 Min Wu A1 Haodi Cai A1 Qiushi Lv A1 Rui Liu A1 Dong Yang A1 Xinfeng Liu YR 2021 UL http://svn.bmj.com/content/early/2021/07/08/svn-2021-000949.abstract AB Background and purpose Whether the off-hour effect has an impact on workflow and outcomes of endovascular treatment (EVT) for anterior circulation large vessel occlusion (AC-LVO) remains uncertain. This study aimed to compare the characteristics and outcomes of patients who presented or were treated during off-hour versus on-hour in a multi-center registry.Methods AC-LVO patients from 21 centres were categorised into the off-hour group and the on-hour group. Off-hour (weekends, holidays, and 18:00–7:59 on weekdays) and on-hour (8:00–17:59 on weekdays except for holidays) were defined according to arrival and groin-puncture time points, respectively. Subgroup comparisons between patients both arrived and treated during off-hour (true off-hour) and on-hour (true on-hour) were performed. The primary outcome was the 90-day modified Rankin Scale (mRS) score. Secondary outcomes included favourable outcome (mRS 0–2 at 90 days), EVT-related time metrics, and other clinical outcomes. Ordinary and binary logistic regression and linear regression were taken to adjust for confounding factors.Results Of all 698 patients enrolled, 435 (62.3%) and 456 (65.3%) patients were categorised into the off-hour arrival and off-hour puncture group, respectively. Shorter onset to door time (adjusted ß coefficient: −21.56; 95% CI −39.96 to −3.16; p=0.022) was noted in the off-hour arrival group. Ordinal and dichotomous mRS scores at 90 days were comparable between the off-hour group and the on-hour group regardless of off-hour definitions. Other time metrics and outcomes were comparable between the two groups. Of 595 patients both presented and were treated during off-hour or on-hour, 394 patients were categorised into the true off-hour group and 201 into the true on-hour group. Time metrics and clinical outcomes were similar between the true off-hour and the true on-hour group.Conclusions The off-hour effect was not significant regarding clinical outcomes and in-hospital workflow in AC-LVO patients receiving EVT in this Chinese multicentre registry.Data are available upon reasonable request. The data that support the findings of this study are available from the corresponding author on reasonable request.