Oral Symptoms and Factors Associated with COVID-19: A Case-Control Study

Coronavirus disease-2019 (COVID-19) is a serious pandemic situation. Assessment of associated factors contributing to its severity is of clinical significance. This study assessed the factors associated with COVID-19 and its severity.

In this case-control study, we assessed self-reports of 93 COVID-19 patients and 50 healthy controls regarding demographics, smoking habit, sinusitis, rhinoplasty or tonsillectomy history, xerostomia, dysosmia, dysgeusia, taste disturbances (metallic taste and foul taste), and bleeding or inflammation in the oral cavity. Further admission to ICU or death were recorded later. We also assessed the patients’ laboratory tests including WBC, neutrophils, lymphocytes, basophils, eosinophils, C reactive protein (CRP), and erythrocyte sedimentation rate (ESR) at the time of admission. Diagnosis of patients was based on clinical assessments, Reverse transcriptase polymerase chain reaction (RT-PCR) and chest computed tomography (CT) scan results. Healthy controls had no flu like signs and symptoms in the past 1 month prior to the study. Associations between the abovementioned factors and disease, and disease severity were analyzed by the Chi-square test, independent-sample t-test, one-sample t-test, and Spearman’s correlation coefficient (α=0.05).

Variables with statistically significant associations with COVID-19 included smoking (P=0.004), xerostomia (P=0.000), dysgeusia (P=0.000), dysosmia (P=0.000), and taste disturbances (P=0.000). CRP (P=0.000), ESR (P=0.000), and neutrophil percentage (P=0.000) were also elevated in patients. Eosinophil (P=0.000) and basophil percentages (P=0.016) were lower than normal range in patients. Age was associated with death (P=0.010) and ICU admission (P=0.009).

Xerostomia, dysgeusia, dysosmia, and taste disturbances can be early markers of COVID-19. Older ages are prone to more severe forms of disease.