One-year psychophysical evaluation of COVID-19-induced olfactory disorders: a prospective cohort study
Abstract Background Olfactory disorders are common in COVID-19. While many patients recover within weeks, a notable number of patients suffer from prolonged olfactory disorders. Much research has focused on the acute phase of olfactory disorders in COVID-19; however, there is still inconsistency reg...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2023-12-01
|
| Series: | BMC Medicine |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s12916-023-03205-x |
| _version_ | 1797397977174638592 |
|---|---|
| author | Emma J. A. Schepens Wilbert M. Boek Sanne Boesveldt Robert J. Stokroos Inge Stegeman Digna M. A. Kamalski |
| author_facet | Emma J. A. Schepens Wilbert M. Boek Sanne Boesveldt Robert J. Stokroos Inge Stegeman Digna M. A. Kamalski |
| author_sort | Emma J. A. Schepens |
| collection | DOAJ |
| description | Abstract Background Olfactory disorders are common in COVID-19. While many patients recover within weeks, a notable number of patients suffer from prolonged olfactory disorders. Much research has focused on the acute phase of olfactory disorders in COVID-19; however, there is still inconsistency regarding the prognosis. We aim to assess both objective and subjective olfactory function in patients with persisting olfactory disorders following COVID-19, 1 year after diagnosis. Methods We objectively measured olfactory function in 77 patients who initially had COVID-19-induced smell disorders, 1 year after confirmed diagnosis. These patients previously underwent two objective measurements at approximately 3 and 6 months after COVID-19, in the context of the COCOS trial (COrticosteroids for COvid-19-induced loss of Smell). The main outcome measurement was TDI score (threshold-discrimination-identification) on Sniffin’ Sticks Test (SST). Secondary outcomes included objective gustatory function on Taste Strip Test (TST), self-reported olfactory, gustatory and trigeminal function on a visual analogue scale (VAS) and outcomes on questionnaires about quality of life, and nasal symptoms. Results The findings of this study show that 1 year following COVID-19, the median TDI score increased to 30.75 (IQR 27.38–33.5), regarded as normosmia. The median TDI score started at 21.25 (IQR 18.25–24.75) at baseline and increased to 27.5 (IQR 23.63–30.0) at 6 months following COVID-19. The increase of 9.5 points on the TDI score between baseline and 1 year after COVID-19 marks a clinically relevant improvement. Regarding the self-reported VAS score (1–10) on sense of smell, it increased from 1.2 (IQR 0.4–3.0) at baseline to 3.2 (IQR 1.4–6.0) at 6 months and further improved up to 6.1 (IQR 2.7–7.5) after 1 year. Objective gustatory function increased with 2 points on TST a year after diagnosis. Self-reported olfactory, gustatory, and trigeminal functions also improved over time, as did quality of life. Conclusions Objective and self-reported olfactory function continued to improve 1 year after COVID-19. The median TDI score of 30.75 (IQR 27.38–33.5) is regarded as normosmia, which is a favorable outcome. However, the rate of improvement on TDI score reduces over time. |
| first_indexed | 2024-03-09T01:18:03Z |
| format | Article |
| id | doaj.art-ddd37a7df6d24d71bc428171370bc22d |
| institution | Directory Open Access Journal |
| issn | 1741-7015 |
| language | English |
| last_indexed | 2024-03-09T01:18:03Z |
| publishDate | 2023-12-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Medicine |
| spelling | doaj.art-ddd37a7df6d24d71bc428171370bc22d2023-12-10T12:21:35ZengBMCBMC Medicine1741-70152023-12-012111910.1186/s12916-023-03205-xOne-year psychophysical evaluation of COVID-19-induced olfactory disorders: a prospective cohort studyEmma J. A. Schepens0Wilbert M. Boek1Sanne Boesveldt2Robert J. Stokroos3Inge Stegeman4Digna M. A. Kamalski5Department of Otorhinolaryngology- Head and Neck Surgery, University Medical Center UtrechtDepartment of Otorhinolaryngology- Head and Neck Surgery, Hospital Gelderse ValleiDivision of Human Nutrition and Health, Wageningen UniversityDepartment of Otorhinolaryngology- Head and Neck Surgery, University Medical Center UtrechtDepartment of Otorhinolaryngology- Head and Neck Surgery, University Medical Center UtrechtDepartment of Otorhinolaryngology- Head and Neck Surgery, University Medical Center UtrechtAbstract Background Olfactory disorders are common in COVID-19. While many patients recover within weeks, a notable number of patients suffer from prolonged olfactory disorders. Much research has focused on the acute phase of olfactory disorders in COVID-19; however, there is still inconsistency regarding the prognosis. We aim to assess both objective and subjective olfactory function in patients with persisting olfactory disorders following COVID-19, 1 year after diagnosis. Methods We objectively measured olfactory function in 77 patients who initially had COVID-19-induced smell disorders, 1 year after confirmed diagnosis. These patients previously underwent two objective measurements at approximately 3 and 6 months after COVID-19, in the context of the COCOS trial (COrticosteroids for COvid-19-induced loss of Smell). The main outcome measurement was TDI score (threshold-discrimination-identification) on Sniffin’ Sticks Test (SST). Secondary outcomes included objective gustatory function on Taste Strip Test (TST), self-reported olfactory, gustatory and trigeminal function on a visual analogue scale (VAS) and outcomes on questionnaires about quality of life, and nasal symptoms. Results The findings of this study show that 1 year following COVID-19, the median TDI score increased to 30.75 (IQR 27.38–33.5), regarded as normosmia. The median TDI score started at 21.25 (IQR 18.25–24.75) at baseline and increased to 27.5 (IQR 23.63–30.0) at 6 months following COVID-19. The increase of 9.5 points on the TDI score between baseline and 1 year after COVID-19 marks a clinically relevant improvement. Regarding the self-reported VAS score (1–10) on sense of smell, it increased from 1.2 (IQR 0.4–3.0) at baseline to 3.2 (IQR 1.4–6.0) at 6 months and further improved up to 6.1 (IQR 2.7–7.5) after 1 year. Objective gustatory function increased with 2 points on TST a year after diagnosis. Self-reported olfactory, gustatory, and trigeminal functions also improved over time, as did quality of life. Conclusions Objective and self-reported olfactory function continued to improve 1 year after COVID-19. The median TDI score of 30.75 (IQR 27.38–33.5) is regarded as normosmia, which is a favorable outcome. However, the rate of improvement on TDI score reduces over time.https://doi.org/10.1186/s12916-023-03205-xOlfactory disordersSmellCOVID-19Prognosis |
| spellingShingle | Emma J. A. Schepens Wilbert M. Boek Sanne Boesveldt Robert J. Stokroos Inge Stegeman Digna M. A. Kamalski One-year psychophysical evaluation of COVID-19-induced olfactory disorders: a prospective cohort study BMC Medicine Olfactory disorders Smell COVID-19 Prognosis |
| title | One-year psychophysical evaluation of COVID-19-induced olfactory disorders: a prospective cohort study |
| title_full | One-year psychophysical evaluation of COVID-19-induced olfactory disorders: a prospective cohort study |
| title_fullStr | One-year psychophysical evaluation of COVID-19-induced olfactory disorders: a prospective cohort study |
| title_full_unstemmed | One-year psychophysical evaluation of COVID-19-induced olfactory disorders: a prospective cohort study |
| title_short | One-year psychophysical evaluation of COVID-19-induced olfactory disorders: a prospective cohort study |
| title_sort | one year psychophysical evaluation of covid 19 induced olfactory disorders a prospective cohort study |
| topic | Olfactory disorders Smell COVID-19 Prognosis |
| url | https://doi.org/10.1186/s12916-023-03205-x |
| work_keys_str_mv | AT emmajaschepens oneyearpsychophysicalevaluationofcovid19inducedolfactorydisordersaprospectivecohortstudy AT wilbertmboek oneyearpsychophysicalevaluationofcovid19inducedolfactorydisordersaprospectivecohortstudy AT sanneboesveldt oneyearpsychophysicalevaluationofcovid19inducedolfactorydisordersaprospectivecohortstudy AT robertjstokroos oneyearpsychophysicalevaluationofcovid19inducedolfactorydisordersaprospectivecohortstudy AT ingestegeman oneyearpsychophysicalevaluationofcovid19inducedolfactorydisordersaprospectivecohortstudy AT dignamakamalski oneyearpsychophysicalevaluationofcovid19inducedolfactorydisordersaprospectivecohortstudy |