Trends in hospital admissions for chronic obstructive pulmonary diseases during COVID-19 in Beijing: a population-based cohort study

Background: In China, strict COVID-19 mitigation measures brought substantial public health benefits, but ending the zero-COVID policy in December 2022 resulted in a surge in other COVID-19-related incidence and hospitalizations. The actual impact of this policy shift on chronic obstructive pulmonary disease (COPD) hospitalizations has not been empirically estimated. We aim to quantify the effects of implementing and ending COVID-19 related non-pharmaceutical interventions (NPIs) on COPD hospitalization rate. Method: This cohort study analyzed data on hospital in-patient admissions from all the secondary and tertiary hospitals in Beijing during 2015 to 2023. The study period was divided into three phases: pre-pandemic period (January 1, 2015, to January 31, 2020), zero COVID policy period (February 1, 2020 to December 31, 2022), and ending zero COVID policy period (January 1, 2023 to December 31, 2023). We performed an interrupted time series analysis using negative binomial regression to estimate the immediate and gradual changes in the weekly admissions for COPD patients attributable to the implementation and ending of the Zero COVID Policy. Excess risk (ER) estimates representing the overall changes in the relative risks of COPD hospitalizations associated with the implementation and ending of the Zero COVID Policy were derived. Findings: We extracted data for 229,525 cases of COPD in Beijing, China. A stable and unchanged secular trend in COPD hospitalization rates was observed before the COVD-19 outbreak. After the COVID-19 outbreak, we noted significant immediate decreases COPD hospitalizations (RR=0.50, 95% CI: 0.46 to 0.54; p<0.001). Hospitalizations gradually rebounded over time since April 2020 when many government-imposed mobility restrictions were lifted. Though an 8% (RR=1.08, 95% CI: 1.04 to 1.12; p<0.001) gradual increase in COPD hospitalization rates per year was detected, it had not achieved their pre-pandemic forecasted levels before ending the zero COVID policy. An overall reduction of 38% (ER=0.62, 95%CI: 0.55 to 0.69; p<0.001) in COPD hospitalization rates was observed during the zero COVID policy period. After ending the zero COVID policy, the immediate change in COPD hospitalizations was not statistically significant (RR=0.90, 95% CI: 0.79 to 1.01; p=0.0785). An 33% (RR=1.33, 95% CI: 1.18 to 1.59; p=0.001) gradual increase per year was observed, which resulted in an overall increase of 19% (ER=1.19, 95%CI: 1.18 to 1.21; p<0.001) within 12 months of follow-up. Interpretation: Our study provided evidence for the effectiveness of COVID-19 related NPIs on the significant reductions in COPD hospitalization rates. Importantly, COPD hospitalizations quickly rebounded after ending the zero COVID policy, warranting targeted approaches to address potentially increased the burden of COPD in China due to the cancellation of COVID-19 related NPIs.