Frequency and predictive validity of olfactory and taste dysfunction in patients with SARS-CoV-2 infection.

Background And Objective: Olfactory and taste dysfunction (OD, TD) have been considered symptoms of SARS-CoV-2 infection. However, its presence in certain populations, especially those with mild clinical symptoms, has not been clarified. The objective was to estimate the frequency of OD and TD, and its predictive validity in patients detected in Primary Care.

Patients And Methods: A cross-sectional study was carried out in the Spanish National Health System. An epidemiological survey was administered to patients who were requested the PCR test for SARS-CoV-2. Odds ratio (OR) were estimated to measure the magnitude of the association between OD and TD and the existence of SARS-CoV-2 infection. The sensitivity, specificity, and positive and negative predictive values (PPV, NPV) of these symptoms in SARS-CoV-2 infection were calculated.

Results: Of 1,038 patients screened, 20.1% had SARS-CoV-2 infection. OD and DG were present in 64.4% (95% CI 56.0-72.1) and 56.2% (95% CI 47.9-64.2) of the subjects with infection, respectively. The OR for OD was 12.2 (95% CI 8.26-18.06) and for TD was 7.95 (95% CI 5.48-11.53). TD presented a sensitivity of 41.1% (95% CI 34.4-46.1), a specificity of 91.9% (95% CI 89.8-93.7), a PPV of 56.2% (95% CI48.0-64.2) and a NPV of 86.1% (95% CI 83.6-88.3), while the OD showed a sensitivity of 45.0% (95% CI 37.6-51.5), a specificity of 93.7% (95% CI 91.8-95.0), a PPV of 64.4% (95% CI 56.0-72.1) and a NPV of 87.1% (95% CI 84.7-89.2).

Conclusions: More than half of the subjects with SARS-CoV-2 infection have OD or TD. The presence of OD or TD could be of diagnostic utility due to its ability to predict infection in more than half of the cases.