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Optimized Management of Endovascular Treatment for Acute Ischemic Stroke
Published on: January 18, 2018
Changes in inpatient and outpatient stroke admissions during COVID-19: a difference-in-differences analysis based on
Kazuhiro Abe1,2,3, Shota Shibata4,5, Atsushi Miyawaki2,6
1Department of Social and Behavioral Sciences, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA.
Insights
During COVID-19, overall stroke admissions in Japan remained stable, with fewer ischemic stroke hospitalizations offset by more outpatient cases. Stroke care was appropriately managed despite resource limitations.
Area of Science:
- Neurology
- Public Health
- Epidemiology
Background:
- COVID-19 is linked to increased stroke risk due to prothrombotic and inflammatory effects.
- Studies noted decreased stroke hospitalizations during the pandemic, possibly due to outpatient follow-ups.
- Investigating changes in inpatient and outpatient stroke admissions during COVID-19 is crucial.
Purpose of the Study:
- To analyze the impact of the COVID-19 pandemic on stroke admissions in Japan.
- To compare stroke admission numbers in inpatient and outpatient settings before and during the pandemic.
- To assess changes in stroke types, mortality, and treatment rates.
Main Methods:
- A difference-in-differences design was used with claims data from 242 acute-care hospitals in Japan.
- Data from the pre-pandemic period (2015-2019) were compared to the pandemic period (2020).
- The study examined ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage admissions, alongside mortality and treatment rates.
Main Results:
- No statistically significant change in overall stroke admissions was observed during the pandemic.
- Ischemic stroke hospitalizations decreased (IRR 0.83), while outpatient cases showed an increasing trend (IRR 1.06).
- Mechanical thrombectomy rates for ischemic stroke decreased (0.60), and length of stay was reduced for most stroke types.
Conclusions:
- Overall stroke admissions in Japan remained stable in 2020 when considering both inpatient and outpatient settings.
- Acute stroke care was managed appropriately during the pandemic despite resource constraints.
- Findings highlight the importance of monitoring both inpatient and outpatient trends for stroke care during public health crises.
Introduction:
While COVID-19 has been associated with an elevated stroke risk due to its prothrombotic and inflammatory effects, previous studies have reported a decreased number of stroke hospitalisations during COVID-19. Patients with a stroke who could not be admitted might have been followed up in outpatient settings of these hospitals. Our study aimed to investigate the change in the number of patients who had a stroke admitted to inpatient and outpatient settings during COVID-19.
Methods:
A difference-in-differences design using claims data in 242 acute-care hospitals was adopted to examine stroke admissions in Japan, contrasting the pre-pandemic period (2015-2019) to the pandemic period (2020). The Japanese government's declaration of emergency in April 2020 was considered an exogenous shock. The outcomes were the numbers of ischaemic stroke (both embolic and non-embolic), intracerebral haemorrhage and subarachnoid haemorrhage admissions, with in-hospital mortality rates, modified Rankin Scale and procedure uses.
Results:
From a total of 27 631 stroke cases (44.3% women, median age 75 years (IQR 66-83)), no statistically significant changes were observed in the overall count of stroke admissions during the pandemic. A decrease in ischaemic stroke hospitalisations was detected (incidence-rate ratios (95% CI), 0.83 (0.73 to 0.95)), which was somewhat offset by an increasing trend for patients treated in the outpatient setting (1.06 (0.91 to 1.22)). No significant differences were found in in-hospital mortality rate, proportion of severe modified Rankin Scale at discharge and thrombolysis treatment rate. Rates of mechanical thrombectomy in ischaemic stroke were reduced (0.60 (0.36 to 0.99)), and length of stay was reduced for all types of stroke except intracerebral haemorrhage.
Conclusion:
When considering both inpatient and outpatient admissions for stroke, we found no statistically significant change in the number of stroke admissions in 2020 in Japan. In addition, our findings suggest that acute stroke inpatient care, at least during 2020, was appropriately managed despite limited resources.
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