Peer-reviewed article
Impact of the COVID-19 pandemic and COVID-19 downgrade on non-COVID-19 respiratory diseases in Japan.
Yamaguchi S, Okada A, Ono S, Inoue R, Kurakawa KI et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study examined how COVID-19 and its prevention measures affected respiratory disease rates in Japan using nationwide insurance and mortality data from 2017 to 2023. During the pandemic, hospitalizations for pneumonia, asthma, and aspiration pneumonia decreased, likely due to prevention measures. When Japan lifted these measures in May 2023, hospitalizations and asthma medication prescriptions increased sharply, particularly in children aged 0-5 years. Deaths from respiratory diseases did not immediately increase after the measures were lifted.
Key points
- Hospitalization rates for pneumonia, asthma, and aspiration pneumonia fell during the COVID-19 pandemic due to non-pharmaceutical interventions
- Following COVID-19 downgrade on May 8, 2023, there was a step increase in hospitalizations for these diseases and anti-asthma drug prescriptions
- Children aged 0-5 years showed the most pronounced impact from lifting COVID-19 measures
- Mortality from non-COVID-19 respiratory diseases decreased during the pandemic and did not show immediate increase after downgrade
- The study analyzed data from 16,485,812 insured individuals using interrupted time series analysis
Limitations
The study cannot establish causation for the hospitalization increases after COVID-19 downgrade, as multiple factors may have contributed (seasonal patterns, behavioral changes, rebound effects). The analysis relies on insurance claims data which may not represent the entire Japanese population.
Abstract
Objectives A worldwide decrease in the incidence of respiratory diseases during the coronavirus disease (COVID-19) pandemic has been reported, largely due to non-pharmaceutical interventions (NPIs). However, the impact of lifting NPIs remains unclear. In Japan, NPIs were lifted rather drastically when COVID-19 was downgraded on May 8, 2023. This study aimed to evaluate the impact of the COVID-19 pandemic and its downgrade on non-COVID-19 respiratory diseases using nationwide databases. Study design Retrospective cohort study. Methods Monthly hospitalisation and prescription rates between January 2017 and October 2023 were collected from the JMDC insurance claims database covering 16,485,812 insured individuals. The monthly mortality rates in Japan were collected from an open data source published by Ministry of Health, Labour and Welfare of Japan. Interrupted time series analyses using seasonal autoregressive integrated moving average models were performed. Results While hospitalisation rates for diseases such as pneumonia, asthma, and aspiration pneumonia decreased during the pandemic, a step increase in hospitalisations for these diseases and prescriptions for anti-asthma drugs was observed following the COVID-19 downgrade. The pandemic impacted all age groups; however, the impact of COVID-19 downgrade was more pronounced in children aged 0-5 years. Although mortality from non-COVID-19 respiratory diseases decreased during the pandemic, no immediate step increase in mortality was observed following the downgrade. Conclusions Although hospitalisations for pneumonia and prescriptions for anti-asthma drugs increased immediately after downgrading COVID-19, no step increase in mortality was observed presumably because older people were less affected than children.
Findings the Hub has extracted
Each claim below is labelled by its type of design and links back to this report.
- Intervention
- Lifting of non-pharmaceutical interventions (mask-wearing, social distancing, quarantine measures) when COVID-19 was downgraded on May 8, 2023
- Population
- Japanese population covered by JMDC insurance (16,485,812 insured individuals), with particular focus on children aged 0-5 years
Key finding
Step increase in hospitalizations for pneumonia, asthma, and aspiration pneumonia observed following COVID-19 downgrade