Changes in rehabilitation service utilisation during COVID-19 bed surges in Japan: a seasonal autoregressive integrated moving average (SARIMA) analysis of care utilisation with 10-year claims data.

OBJECTIVE

To explore the association between COVID-19 bed utilisation and changes in rehabilitation service provision in Japan, focusing on cerebrovascular, musculoskeletal and respiratory rehabilitation in the pre-COVID-19, during-COVID-19 and post-COVID-19 periods.

DESIGN

Retrospective study using seasonal autoregressive integrated moving average model to predict expected values, which were compared with actual values to calculate observed-to-expected (OE) ratios.

SETTING

Acute care hospitals in Kanagawa Prefecture, which has the second largest population in Japan after Tokyo, covering April 2014 to March 2024.

PARTICIPANTS

Patients aged 0-74 years who were enrolled in the National Health Insurance of Kanagawa Prefecture and underwent the studied types of rehabilitation.

EXPOSURE: COVID-19 pandemic waves and associated bed utilisation rates, with multiple distinct peaks.

OUTCOME MEASURES: The difference between the predicted and actual values of the volume of rehabilitation services provided and the number of patients per insured person calculated as OE ratios during periods of peak bed utilisation for COVID-19.

RESULTS

The OE ratio of inpatient rehabilitation services for cerebrovascular showed a significant decrease after five waves at -14.3%, and musculoskeletal conditions showed a similar decline during periods of high COVID-19 bed utilisation. Outpatient services experienced sharp declines initially but showed differential recovery patterns. Respiratory rehabilitation displayed unique patterns, with inpatient services increasing up to 62.4% above expected levels until September 2021, before sharply declining. By March 2024, musculoskeletal rehabilitation demonstrated complete recovery, cerebrovascular rehabilitation showed partial recovery, while respiratory rehabilitation exhibited mixed patterns with persistent outpatient deficits.

CONCLUSIONS

Rehabilitation services in Japan showed substantial changes associated with the COVID-19 pandemic, with inpatient services for cerebrovascular and musculoskeletal conditions being particularly vulnerable to disruptions during high COVID-19 bed utilisation periods. The differential recovery patterns across rehabilitation types, with some structural changes persisting beyond the acute pandemic phase, indicate the need for flexible healthcare systems to deal with future healthcare crises. These findings underscore the importance of developing strategies to maintain essential rehabilitation services during public health emergencies, especially considering the ageing global population and rising demand for rehabilitation.