May 12, 2020

Smoking and COPD associated with higher COVID-19 mortality

By Denise Baez

Current smokers and people with chronic obstructive pulmonary disease (COPD) who contract coronavirus disease 2019 (COVID-19) have an increased risk of severe complications and higher mortality with COVID-19 infection, according to a study published in PLOS ONE.

Jaber Alqahtani, University College London, London, United Kingdom, and colleagues scrutinised data from 15 studies comprising 2,473 patients with laboratory-confirmed COVID-19. Data were extracted by 2 independent authors in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

The crude case fatality rate of COVID-19 was 7.4%. The pooled prevalence rate of patients with COPD with COVID-19 was 2% and 9% for smokers with COVID-19. Patients with COPD were at a higher risk of more severe disease (risk of severity = 63%) compared with patients without COPD (33.4%), and had a higher mortality risk (60% vs 55%).

Of current smokers, 22% had severe complications compared with 46% of ex-smokers. In addition, current smokers were 1.45 times more likely to have severe complications compared with former and never smokers. Current smokers also had a higher mortality rate of 38.5%.

“To the best of our knowledge, this is the first systematic review and meta-analysis to develop an informed understanding of the prevalence, severity and mortality of patients with COPD diagnosed with COVID-19,” the authors wrote.

“Although COPD prevalence in COVID-19 cases was low in current reports, COVID-19 infection was associated with substantial severity and mortality rates in COPD,” they added. “Compared with former and never smokers, current smokers were at greater risk of severe complications and higher mortality rate. Effective preventive measures are required to reduce COVID-19 risk in patients with COPD and current smokers.”

“Having a reliable estimate of the prevalence of COPD in COVID-19 cases, and likely outcomes, is crucial to ensure specific successful global preventive and treatment strategies for patients with COPD,” the authors added. “Bearing this in mind, in the included studies there was no report on COPD severity data and COPD-related comorbidities, which prevents us from assessing the impact of such essential information.”