Our study has some limitations. In addition to not having measured lung volumes with plethysmography, we do not have any baseline lung function data in these patients prior to SARS-CoV-2 infection or a control group due to the pandemic to perform further analysis. However, most studies involving lung function analysis among COVID-19 survivors were done with the same limitation. Indeed, it is difficult to determine with certainty that these patients with poor diffusing capacity and/or a restrictive spirometric pattern are due to them having mild COVID-19. Nonetheless, these patients are compared against established reference norms. The prevalence of an impaired DLCO in our sample was five times more than expected in a normal population and at least two-fold more than expected for a restrictive spirometric pattern. To reduce this bias, we analysed all risk factors related to lung function abnormalities, including published studies. Also, there is a gap in implementing regular lung function assessments in suspected obstructive lung disease cases. Instead, chest x-ray studies are more frequently requested, especially in countries with limited-resource settings; therefore, it is expected that patients were not subjected to pulmonary function tests prior to SARS-CoV-2 infection.
BMC Pulm Med. 2022;22(294) © 2022 BioMed Central, Ltd.