Evaluation of the relationship between laboratory parameters and pulmonary function tests in COVID-19 patients

The novel coronavirus SARS-CoV-2 (COVID-19) rapidly escalated from its origin in an animal market in Wuhan, China in December 2019 to a global pandemic, and the lungs are the most frequently affected organ. The aim of this study was to investigate the relationship between pulmonary function test parameters and laboratory parameters in COVID-19.

A total of 60 patients who were admitted to the chest diseases department and intensive care unit of our hospital and were diagnosed with COVID-19 by real-time PCR analysis of nasopharyngeal swabs were evaluated. Pulmonary function tests and laboratory parameters at admission and on day 7 of treatment were analysed.

On day 7 of treatment, white blood cell count, CRP, and fibrinogen level were significantly lower than at admission (P = .002, 0.001, and 0.001, respectively), while forced expiratory volume in the first second (FEV₁ ) and forced vital capacity (FVC) values were significantly higher compared with admitting values (P = .001 for both). Correlation analysis showed that the decrease in CRP from admission to day 7 of treatment correlated with the increase in FEV₁ (r = 0.616, P = .01) and FVC (r = 0.51, P = .01) during the same period. A decrease in the fibrinogen level was also correlated with an increase in FEV₁ (r = 0.345, P = .01) and FVC (r = 0.357, P = .01).

Fibrinogen and CRP levels are easily accessible parameters that may help identify improvement or deterioration in pulmonary function in COVID-19 patients during follow-up and discharge while reducing the risk of transmission.