Impact of the COVID-19 pandemic on emergency admission for patients with stroke: a time series study in Japan

BACKGROUND: Appropriate treatment of stroke immediately after its onset contributes to the improved chances, while delay in hospitalisation affects stroke severity and fatality. This study aimed to determine the impact of the coronavirus disease 2019 (COVID-19) pandemic on emergency hospitalisation of patients with stroke in Japan. METHODS: This was an observational study that used nationwide administrative data of hospitalised patients diagnosed with stroke. We cross-sectionally observed patients’ background factors during April and May 2020, when the COVID-19 pandemic-related state of emergency was declared; we also observed these factors in the same period in 2019. We also modelled monthly trends in emergency stroke admissions, stroke admissions at each level of the Japan Coma Scale (JCS), fatalities within 24 h, stroke care unit use, intravenous thrombolysis administration, and mechanical thrombectomy implementation using interrupted time series (ITS) regression. RESULTS: There was no difference in patients’ pre-hospital baseline characteristics between the pre-pandemic and pandemic periods. However, ITS regression revealed a significant change in the number of emergency stroke admissions after the beginning of the pandemic (slope: risk ratio [RR] = 0.97, 95% confidence interval [CI]: 0.95–0.99, P = 0.027). There was a significant difference in the JCS score for impaired consciousness in emergency stroke, which was more severe during the pandemic than the pre-pandemic (JCS3 in level: RR = 1.75, 95% CI: 1.29–2.33, P < 0.001). There was no change in the total number of fatalities with COVID-19, compared with those without COVID-19, but there were significantly more fatalities within 24 h of admission (fatalities within 24 h: RR = 1.75, 95% CI: 1.29–2.33, P < 0.001). CONCLUSIONS: The infection prevalence of COVID-19 increased the number of fatalities within 24 h as well as the severity of illness in Japan. However, there was no difference in baseline characteristics, intravenous thrombolysis administration, and mechanical thrombectomy implementation during the COVID-19 pandemic. A decrease in the number of patients and fatalities was observed from the time the state of emergency was declared until August, the period of this study.