Olfactory and Gustatory Outcomes Including Health-Related Quality of Life 3–6 and 12 Months after Severe-to-Critical COVID-19: A SECURe Prospective Cohort Study

Abstract

Background: Long-term follow-up studies of COVID-19 olfactory and gustatory disorders (OGDs) are scarce. OGD, parosmia, and dysgeusia affect health-related quality of life (HRQoL) and the ability to detect potential hazards. Methods: In this study, 29 patients reporting OGD 1 month after severe-to-critical COVID-19 were tested at 3–6 months and retested at 12 months in case of hyposmia/anosmia. We used Sniffin Sticks Threshold, Discrimination, and Identification (TDI) test, Sniffin Sticks Identification Test (SIT16), Brief Smell Identification Test (BSIT), taste strips, and HRQoL. The patients were part of the prospective SECURe cohort. Results: Overall, 28% OD (TDI), 12% GD, 24% parosmia, and 24% dysgeusia (questionnaire) at 3–6 months (n = 29) and 28% OD (TDI), 38% parosmia, and 25% dysgeusia (questionnaire) at 12 months (n = 8) were observed. OGD decreased HRQoL: For 13%, it had a negative effect on daily life and, for 17%, it affected nutrition, 17% reported decreased mood, and 87–90% felt unable to navigate everyday life using their sense of smell and taste. A comparison of SIT16 and BSIT to TDI found sensitivity/specificity values of 75%/100% and 88%/86%. Conclusions: This is the first study to examine TDI, SIT16, BSIT, taste strips, and HRQoL up to 1 year after severe-to-critical COVID-19. The patients suffering from prolonged OGD, parosmia, and dysgeusia experienced severely decreasing HRQoL. We recommend including ear–nose–throat specialists in multidisciplinary post-COVID clinics.

Persistent Olfactory and Taste Dysfunction after COVID-19

“…The results of the other parts of the test (discrimination and identification) were significantly better, suggesting that if the stimulus is intense enough, incorrect discrimination and identification of odors are less frequent. Similar results have been obtained by other authors, both in patients shortly after a positive COVID-19 test result and in those with ODs lasting more than 4 weeks [ 6 , 14 , 22 , 23 , 24 , 25 , 26 ]. In all studies in which the SST was used to assess OD, the threshold test had the most significant effect on the overall test score.…”

“…More recent findings by Prem and colleagues indicate that in patients with short-lasting disorders (up to 4 weeks), TS scores correlate well with information from medical interviews, whereas there is a weak correlation between persistent GD and OD [ 26 , 28 ]. Some publications have found a different prevalence of disorders depending on the taste concerned: for example, in the study by Arndal et al, the least recognized taste was bitter [ 14 ], while Singer-Cornelius et al found it was sour [ 29 ].…”

“…Persistent OD and/or GD (OGD) are common symptoms of post-COVID-19 syndrome. They are a significant problem for those afflicted, as they cause psychological distress and reduce quality of life [ 14 , 15 ].…”

Reply to: Letter to the editor regarding “Long‐term quality‐of‐life impairment in patients with more than 1‐year COVID‐19–related olfactory dysfunction”

“…Although we did not use any taste strips to confirm that, a good correlation between these and reported TD has been described in the past. 2 Moreover, the absence of patients reporting a TD in our population corroborates previous studies 3,4 that show how long-term COVID-19-related TD is much less prevalent than persistent OD.…”

Complicaciones neurológicas periféricas en pacientes adultos Post-Covid-19, Revisión sistemática

“…El diagnóstico depende de pruebas complementarias (2). Para identificar la anosmia y disgeusia se sugiere una prueba de olfato 16 (SIT16) y una prueba de gustometría (3).…”