London, May 12 (IANS) Current smokers and people with chronic obstructive pulmonary disease (COPD) have an increased risk of severe complications and higher mortality with COVID-19 infection, warn researchers.
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 study, published in the journal PLOS ONE, sought to understand the prevalence and the effects of COPD in COVID-19 patients.
"Despite the low prevalence of COPD and smoking in COVID-19 cases, COPD and current smokers were associated with greater COVID-19 severity and mortality," said study researchers from University College London in the UK.
For the results, the research 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.
According to the team, 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 per cent) of those patients also had COPD while 221 (9 per cent) were smokers.
The findings showed that critically ill COVID-19 patients with COPD had a 63 per cent risk of severe disease and a 60 per cent risk of mortality while critically ill patients without COPD had only a 33.4 per cent risk of severe disease and 55 per cent risk of mortality.
In addition, current smokers were 1.45 times more likely to have severe complications compared to former and never smokers.
However, 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, the researchers said.
Last month, a study published in the journal American Journal of Respiratory and Critical Care Medicine, suggested that there is an increased risk for the virus binding and gaining entry into the lungs of smokers than non-smokers
Another study, published in European Respiratory Journal claimed that COPD and people who currently smoke have a higher level of an enzyme called 'angiotensin-converting enzyme II' (ACE-2), which is the entry point for coronavirus in lungs.