Loss of smell in COVID-19 patients: is it related to clinical-radiological disease severity?

Abstract

Objective: Olfactory dysfunction (OD) is one of the most prominent predictive symptoms in the early detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) disease (COVID-19), it may be the first symptom or accompany other symptoms. The predictive value of OD is unknown in terms of the overall prognosis of COVID-19. We aimed to investigate the relationship between OD and the clinical-radiological severity of the disease. Material and Method: Data of 208 COVID-19 patients (105 inpatients and 103 outpatients) who had positive Real-Time Polymerase Chain Reaction (PCR) tests between December 1, 2020, and January 15, 2021, were collected retrospectively. Presence of OD, symptoms on admission other than OD, days of hospital stay, peripheral blood analysis values, COVID-19 disease severity [World Health Organization (WHO) 2020 “Clinical management of COVID-19”] and radiologic classifications [Radiological Society of North America Expert Consensus Statement on Reporting (RSNA) Chest CT Findings Related to COVID-19] were retrospectively collected. Results: Analysis of 208 patients revealed that there were 105 (50.48%) inpatients and 103 (49.52%) outpatients. Among 102 patients who had OD, 68 were outpatients and 34 were inpatients. It was determined that the patients with OD were mostly followed up on an outpatient basis, and they did not need hospitalization (p<0.0001). The mean of hospital stay of 34 inpatients with OD was 7.52±4.63 days, while the mean of hospital stay of 71 patients without OD was 12.53±8.92 days, and those with OD were found to need a shorter hospital stay (p=0.001) and no relation was found between disease severity and the duration of OD (p=0.381). There was no significant difference in disease severity in relation to OD in the inpatient group (p=0.71). Conclusion: OD is one of the most common symptoms of COVID-19. In the patients with loss of smell, the need for hospitalization is less, and hospital stay is shorter; these findings indicate that the patients with OD may experience a milder disease. The presence of OD may be used as a useful predictor by clinicians for the severity of the COVID-19 course.

Keywords

• COVID-19
• Loss of Smell
• Disease severity

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