IMPACT OF THE CORONAVIRUS DISEASE 2019 PANDEMIC ON SURGICAL VOLUME IN JAPAN: A COHORT STUDY USING ADMINISTRATIVE DATA (preprint)

ABSTRACT

BackgroundInternationally, the Coronavirus Disease (COVID-19) pandemic has caused unprecedented challenges for surgical staff to minimise the exposure to COVID-19 or save medical resources without harmful outcomes for patients, in accordance with the statement of each surgical society. However, no research has empirically validated declines in Japanese surgical volume or compared decrease rates of surgeries during the COVID-19 pandemic. Material and MethodsWe extracted 672,772 available cases of patients aged > 15 years who were discharged between July 1, 2018, and June 30, 2020. After categorisation of surgery, we calculated descriptive statistics to compare the year-over-year trend and conducted interrupted time series analysis to validate the decline. ResultsThe year-over-year trend of all eight surgical categories decreased from April 2020 and reached a minimum in May 2020 (May abdominal, 68.4%; thoracic, 85.8%; genitourinary, 78.6%; cardiovascular, 90.8%; neurosurgical, 69.1%; orthopaedic, 62.4%; ophthalmologic, 52.0%; ear/nose/throat, 27.3%). Interrupted time series analysis showed no significant trends in oncological and critical benign surgeries. ConclusionWe demonstrated and validated a trend of reduction in surgical volume in Japan using administrative data applying interrupted time series analyses. Low priority surgeries, as categorised by the statement of each society, showed obvious and statistically significant declines in case volume during the COVID-19 pandemic.