Keywords: COVID-19; SARS-CoV-2; olfaction disorders, dysgeusia
Olfactory and taste dysfunction (OD,TD) have been considered symptoms attributable to SARS-CoV-2 infection. Although these clinical features may occur prior to the general symptoms of such infection, their presence in certain populations, especially those with mild symptoms, has not been clarified.
The aim of the study was to estimate the frequency of OD and TD, and its predictive validity in patients with SARS-CoV-2 infection detected in Primary Care.
What is the frequency of OD and TD, and its predictive validity in patients with SARS-CoV-2 infection detected in Primary Care?
A cross-sectional study was carried out in the Spanish National Health System through an epidemiological survey administered to patients who required the RT-PCR test (real-time polymerase chain reaction in a nasal/pharyngeal swab) for the detection of SARS-CoV-2. Odds Ratio(OR)(s) were estimated to measure the magnitude of the association between OD or TD, and the presence of SARS-CoV-2 infection. Sensitivity, specificity, and positive and negative predictive values (PPV,NPV) of these symptoms were also calculated in the study sample.
Of 1038 patients screened, 209(20.1%) had SARS-CoV-2 infection. OD and DG were detected in 64.4%(95%CI: 56.0-72.1) and 56.2% (95%CI:47.9-64.2) of subjects with infection, respectively. The OR for OD and TD was 12.2(95%CI: 8.26-18.06) and 7.95 (95%CI: 5.48-11.53), respectively. 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), while the 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%CI: 48.0-64.2) and a NPV of 86.1% (95%CI :83.6-88.3).
More than half of the subjects with SARS-CoV-2 infection have olfactory or taste dysfunction. The presence of these clinical features could be considered of diagnostic utility due to its ability to predict infection in more than half of the cases.
Points for discussion:
Frequence of OD and TD in patients with SARS-CoV-2 infection detected in Primary Care
Predictive validity of OD and TD in patients with SARS-CoV-2 infection detected in Primary Care