COPD and smoking associated with higher COVID-19 mortality: study
Current smokers and people with chronic obstructive pulmonary disease (COPD) have an increased risk of severe complications and higher mortality with COVID-19 infection, according to a new study published May 11, 2020 in the open-access journal PLOS ONE by Jaber Alqahtani of University College London, UK, and colleagues.
COPD is a common, persistent dysfunction of the lung associated with a limitation in airflow. An estimated 251 million people worldwide are affected by COPD. Given the effects of the SARS-CoV-2 coronavirus on respiratory function, the authors of the present study sought to understand the prevalence and the effects of COPD in COVID-19 patients.
In the new study, researchers systematically searched databases of scientific literature to find existing publications on the epidemiological, clinical characteristics and features of COVID-19 and the prevalence of COPD in COVID-19 patients. 123 potentially relevant papers were narrowed to 15 that met all quality and inclusion guidelines. The included studies had a total of 2473 confirmed COVID-19 patients. 58 (2.3%) of those patients also had COPD while 221 (9%) were smokers.
Critically ill COVID-19 patients with COPD had a 63% risk of severe disease and a 60% risk of mortality while critically ill patients without COPD had only a 33.4% risk of severe disease (RR 1.88, 95% CI 1.4-2.4) and 55% risk of mortality (RR 1.1, 95% CI 0.6-1.8). In addition, current smokers were 1.45 times more likely to have severe complications compared to former and never smokers (95% CI 1.03-2.04). The study was not able to examine whether there was an association between the frequency of COPD exacerbations, or severity of COPD, with COVID-19 outcomes or complications. The results are limited by the fact that few studies were available to review, as well as the diverse locations, settings, and designs of the included studies.