Covid-19 patients with only upper respiratory symptoms are likely to have favorable clinical outcomes compared to those who have only lower respiratory symptoms, suggests a study published in the journal Respiratory Research.¹

In this study, researchers evaluated to describe the upper and lower respiratory symptoms in hospitalized COVID-19 patients and also to investigate the impact of these symptoms on patient outcomes. Data on respiratory symptoms for this multicenter retrospective cohort study was collected from February 2020 to November 2021 from the Japan COVID-19 Task Force database.

Out of the 3314 patients included in the study, 1331 had upper respiratory symptoms, 1229 had lower respiratory symptoms, 1149 had both upper and lower respiratory symptoms, while 605 had no respiratory symptoms.

The likelihood of complications such as pneumonia, secondary infections and thrombosis was increased 3-folds among patients who had only lower respiratory symptoms. These patients were more likely to die or require oxygen supplementation, which was the primary outcome of the study. Conversely, patients who had only upper respiratory symptoms had the best outcomes amongst all the patients examined.

Sore throat was the commonest upper respiratory symptoms; the other symptoms were dysgeusia, dysosmia and nasal discharge. The lower respiratory symptoms included cough (most common), dyspnea, sputum production. Fever, fatigue and diarrhea were the extrapulmonary symptoms common to all groups. Patients with lower respiratory symptoms had more fever and fatigue. The symptom with the most favorable prognosis was dysosmia (odds ratio 0.32), while the symptom associated with the worst prognosis was dyspnea with OR of 5.56. Compared to those with upper respiratory symptoms, ground-glass opacities (GGOs) were more often seen in Group 3 and 4 patients.

This study has characterized the upper and lower respiratory symptoms in Covid-19 patients and has also shown that patients with lower respiratory symptoms were more likely to have poorer prognosis compared to those with upper respiratory symptoms, which were associated with favorable patient outcomes.

Reference

1. Nakagawara K, et al. Impact of upper and lower respiratory symptoms on COVID-19 outcomes: a multicenter retrospective cohort study. Respir Res. 2022 Nov 15;23(1):315. doi: 10.1186/s12931-022-02222-3.