Hospital Admission Rates in Patients with COPD Throughout the COVID-19 Pandemic

Abstract

Purpose

Several studies report decreased hospital admissions for acute exacerbations of COPD (AECOPD) during the COVID-19 pandemic. However, there are no studies that compare AECOPD admissions with admissions for respiratory infections, including COVID-19. This study aimed to examine hospital admission rates for AECOPD, pneumonia, influenza, and COVID-19 among COPD patients, before and during the COVID-19 pandemic.

Patients and Methods

We obtained anonymized data on hospital admissions of patients with COPD and a primary diagnosis code for AECOPD, pneumonia, influenza, or COVID-19, from the hospital patient admission register at a large Swedish hospital. The study compared the pandemic period (February 2020–March 2022) to a period before the pandemic (June 2017–January 2020). Sequential phases of the pandemic were evaluated separately. Monthly admission rates were compared using Poisson regression, controlling for admission month.

Results

Comparing monthly admission rates during the pandemic with the prepandemic period, incidence rate ratios were 0.72 for AECOPD (95% CI 0.67–0.77; p<0.001), 0.56 for pneumonia (95% CI 0.49–0.62; p<0.001), 0.18 for influenza during the winter period (95% CI 0.10–0.30; p<0.001) and 0.79 for total COPD admissions, including COVID-19 (95% CI 0.75–0.84; p<0.001). The study showed significantly lower rate ratios for AECOPD, pneumonia, and total COPD admissions during the first, second, third, and fifth (Omicron) waves. No significant effect on admissions was seen after the withdrawal of restriction measures.

Conclusion

There was a significant reduction in the overall rate of hospital admissions among COPD patients for AECOPD, pneumonia, and respiratory viral infections during the pandemic despite the rise in COVID-19 admissions. However, prepandemic admission levels returned in the post-restriction period.

Keywords:

• COPD
• acute exacerbation of COPD
• respiratory viruses
• influenza virus
• COVID-19
• epidemiology

Acknowledgments

We would like to thank Michel Paulli, logistician at the Analysis and Project Unit at Sahlgrenska University Hospital, for helping with data extraction. The abstract of this paper was presented at the ERS International Conference 2022 as a poster presentation with interim findings. The poster’s abstract was published in “ERS International Congress 2022 abstracts” in European Respiratory Journal 04 September 2022; volume 60, issue suppl 66: https://erj.ersjournals.com/content/60/suppl_66/1929.

Disclosure

Dr Lowie EGW Vanfleteren reports personal fees from AstraZeneca, GSK, Boehringer, Novartis, Chiesi, Pulmonx, and Resmed, outside the submitted work. The authors report no other conflicts of interest in this work.

Additional information

Funding

The study was financed by grants from the Swedish state under the agreement between the Swedish government and the county councils, the ALF-agreement (ALFGBG-965569) to J.W. and (ALFGBG-824371) to L.E.G.W.V. and by grants from the Family Kamprad Foundation (20190024) and the Swedish Heart and Lung Foundation (20200150) to L.E.G.W.V.