Respiratory Infection Triggering Severe Acute Exacerbations of Chronic Obstructive Pulmonary Disease

Abstract

Background

Data are scarce on respiratory infections during severe acute exacerbation of chronic obstructive pulmonary disease (COPD). This study aimed to investigate respiratory infection patterns in the intensive care unit (ICU) and identify variables associated with infection type and patient outcome.

Methods

A retrospective, single-centre cohort study. All patients admitted (2015–2021) to our ICU for severe acute exacerbation of COPD were included. Logistic multivariable regression analysis was performed to predict factors associated with infection and assess the association between infection and outcome.

Results

We included 473 patients: 288 (60.9%) had respiratory infection and 139 (29.4%) required invasive mechanical ventilation. Eighty-nine (30.9%) had viral, 81 (28.1%) bacterial, 34 (11.8%) mixed, and 84 (29.2%) undocumented infections. Forty-seven (9.9%) patients died in the ICU and 67 (14.2%) in hospital. Factors associated with respiratory infection were temperature (odds ratio [+1°C]=1.43, P=0.008) and blood neutrophils (1.07, P=0.002). Male sex (2.21, P=0.02) and blood neutrophils were associated with bacterial infection (1.06, P=0.04). In a multivariable analysis, pneumonia (cause-specific hazard=1.75, P=0.005), respiratory rate (1.17, P=0.04), arterial partial pressure of carbon-dioxide (1.08, P=0.04), and lactate (1.14, P=0.02) were associated with the need for invasive MV. Age (1.03, P=0.03), immunodeficiency (1.96, P=0.02), and altered performance status (1.78, P=0.002) were associated with hospital mortality.

Conclusions

Respiratory infections, 39.9% of which were bacterial, were the main cause of severe acute exacerbation of COPD. Body temperature and blood neutrophils were single markers of infection. Pneumonia was associated with the need for invasive mechanical ventilation but not with hospital mortality, as opposed to age, immunodeficiency, and altered performance status.

Plain Language Summary

• - This study investigates the prevalence, characteristics, and impact on outcomes of different types of respiratory infections triggering severe acute exacerbations of COPD.

• - Our retrospective cohort study of 473 critically ill patients found that respiratory infections, of which 39.9% were bacterial, were the main cause of severe exacerbation.

• - The type of infection (viral, bacterial, or mixt) was not associated with the need for invasive mechanical ventilation or mortality.

• - Early identification of the infectious agent is crucial for implementing effective therapy; however, the type of infection was not associated with the main outcomes.

Keywords:

• pneumonia
• infection
• COPD
• mechanical ventilation
• mortality

Data Sharing Statement

The investigators will make the documents and individual data strictly required for monitoring, quality control, and audit of the study available to dedicated persons, in accordance with laws and regulations in force (Articles L.1121-3 and R.5121-13 of the Code de Santé Publique – CSP, French Public Health Code).

The datasets used and/or analyzed during the study will be available from the coordinating investigator (Alexis Ferré) on reasonable request. The procedures carried out under the French data privacy authority (Commission Nationale de l’Informatique et des Libertés) do not permit the transmission of the database, nor do the informed consent documents signed by the patients. Consultation by the editorial board or interested researchers of individual participant data that underlie the results reported in the article after de-identification may nevertheless be considered, subject to prior determination of the terms and conditions of such consultation and in respect of compliance with the applicable regulations.

Ethics Approval and Consent to Participate

This single-center, observational, retrospective study was approved by the ethics committee of the French Intensive Care Society (N° #21-66) and registered at the French National Institute for Health Data (#MR 2516271119). Informed consent was sought from the patients upon recovery, in compliance with French law.

Acknowledgment

Sophie Rushton-Smith, PhD (MedLink Healthcare Communications) provided editorial assistance in the final version of the manuscript and was funded by the Délégation à la Recherche Clinique et à l’Innovation (DRCI), Le Chesnay, France. The abstract of this paper was presented at the French Intensive Care Society International Congress’ in June 2023 as a conference talk with interim findings. The poster’s abstract was published in ‘Poster Abstracts’ in Annals of Intensive Care: [https://doi.org/10.1186/s13613-023-01131-y].

Disclosure

Matthieu Jamme reports honoraria by Sanofi for a lecture during JAMIR Congress 2022, outside the submitted work. Alexis Ferré reports honoraria by Fisher & Paykel for a lecture during SFMU Congress 2022, outside the submitted work. The authors report no other conflicts of interest in this work.

Additional information

Funding

The study was supported by the French public funding agency Délégation à la Recherche Clinique et à l’Innovation (DRCI), Le Chesnay, France.