Universidad de Sevilla. Departamento de Cirugía, Universidad de Sevilla. Departamento de Enfermería, Junta de Andalucía, Fondo Europeo de Desarrollo Regional (FEDER), Callejón-Leblic, María A., Martín-Jiménez, Daniel Iván, Moreno Luna, Ramón, Palacios García, José M., Álvarez Cendrero, M., Vizcarra Melgar, Julissa A., Maza Solano, Juan Manuel, Tena García, Beatriz, Sánchez Gómez, Serafín, Universidad de Sevilla. Departamento de Cirugía, Universidad de Sevilla. Departamento de Enfermería, Junta de Andalucía, Fondo Europeo de Desarrollo Regional (FEDER), Callejón-Leblic, María A., Martín-Jiménez, Daniel Iván, Moreno Luna, Ramón, Palacios García, José M., Álvarez Cendrero, M., Vizcarra Melgar, Julissa A., Maza Solano, Juan Manuel, Tena García, Beatriz, and Sánchez Gómez, Serafín
Background: Although smell and taste disorders are highly prevalent symptoms of COVID 19 infection, the predictive factors leading to long-lasting chemosensory dysfunction are still poorly understood. Methods: 102 out of 421 (24.2%) mildly symptomatic COVID-19 patients completed a second questionnaire about the evolution of their symptoms one year after the infection using visual analog scales (VAS). A subgroup of 69 patients also underwent psychophysical evaluation of olfactory function through UPSIT. Results: The prevalence of chemosensory dysfunction decreased from 82.4% to 45.1% after 12 months, with 46.1% of patients reporting a complete recovery. Patients older than 40 years (OR = 0.20; 95% CI: [0.07, 0.56]) and with a duration of loss of smell longer than four weeks saw a lower odds ratio for recovery (OR = 0.27; 95% CI: [0.10, 0.76]). In addition, 28 patients (35.9%) reported suffering from parosmia, which was associated with moderate to severe taste dysfunction at the baseline (OR = 7.80; 95% CI: [1.70, 35.8]). Among the 69 subjects who underwent the UPSIT, 57 (82.6%) presented some degree of smell dysfunction, showing a moderate correlation with self-reported VAS (r = −0.36, p = 0.0027). Conclusion: A clinically relevant number of subjects reported persistent chemosensory dysfunction and parosmia one year after COVID-19 infection, with a moderate correlation with psychophysical olfactory tests.