Table 1.
Summary of the literature on the association between olfactory dysfunction and COVID-19.
| No. | Publication data | Authors | Country | Study methods | Number of patients | Age (Mean±) |
Diagnosis methods | Prevalence rate% (n=) | Female preponderance | Dysgeusia-related |
|---|---|---|---|---|---|---|---|---|---|---|
| 01 | March 26 | Giacomelli et al. [29] | Italy | Cross-sectional | 59 | Unknown | Questionnaire | 33.9% (n = 20) | Yes | Yes |
| 02 | March 27 | Bagheri et al. [30]* | Iran | Cross-sectional | 10,069 | 32.5 ± 8.6 | Questionnaire | 48.23% (n = 4856) | Yes | Yes |
| 03 | April 1 | Vaira et al. [53] | Italy | Retrospective | 320 | Unknown | Self-reported | 19.4% (n = 62) | Unknown | Yes |
| 04 | April 2 | Gane et al. [25] | United Kingdom | Case report | 1 | 48 | Self-reported | No | ||
| 05 | April 3 | Villalba et al. [54] | France | Case series | 2 | 82.5 | Self-reported | Yes | ||
| 06 | April 5 | Hjelmesæth and Skaare [55] | Norway | Case series | 3 | Unknown | Self-reported | Yes | ||
| 07 | April 6 | Lechien et al. [23] | European countries▲ | Multicenter | 417 | 36.9 ± 11.4 | Questionnaire | 85.6% (n = 357) | Yes | Yes |
| 08 | April 7 | Menni et al. [31] | United Kingdom | Cross-sectional | 579 | 40.79 ± 11.84 | Community survey | 59.41% (n = 344) | Yes | Yes |
| 09 | April 8 | Eliezer et al. [26] | France | Case report | 1 | 40s | Five odorants test★ | No | ||
| 10 | April 12 | Yan et al. [32] | United States | Cross-sectional | 59 | Unknown | Self-reported | 68% (n = 40) | Unknown | Yes |
| 11 | April 16 | Klopfenstein et al. [27] | France | Retrospective | 114 | 47 ± 16 | Self-reported | 47% (n = 54) | Yes | Yes |
| 12 | April 17 | Moein et al. [35] | Iran | Case-control | 60 | 46.55 ± 12.17 | UPSIT★★ | 98.33% (n = 59) | No | Unknown |
| 13 | April 22 | Spinato et al. [33] | United Kingdom | Cross-sectional | 202 | 56 ± 11 | Telephone interviews | 64.4% (n = 130) | Yes | Yes |
| 14 | April 22 | Heidari et al. [24] | Iran | Case series | 23 | 37.4 | Self-reported | 69.57% (n = 16) | Yes | Unknown |
| 15 | April 22 | Beltran-Corbellini et al. [36] | Spain | Case-control | 79 | 52.6 ± 17 | Self-reported | 31.65% (n = 25) | Unknown | Yes |
| 16 | April 24 | Yan et al. [56] | United States | Retrospective | 169 | 53.5 | Self-reported | 75.7% (n = 128) | Unknown | Yes |
| 17 | April 27 | Ottaviano et al. [37] | Italy | Case series | 6 | Unknown | Le nez du vin★★★ | Unknown | Unknown | |
| 18 | April 28 | Kaye et al. [57] | Multiple countries▲▲ | Reporting tool | 237 | 39.6 ± 14.6 | Self-reported | Yes | Unknown | |
| 19 | April 29 | Gilani et al. [58] | Iran | Case series | 5 | 35.6 | Self-reported | Yes | Unknown | |
| 20 | May 1 | Luers et al. [28] | Germany | Retrospective | 72 | 38 ± 13 | Self-reported | 74% (n = 53) | No | Yes |
| 21 | May 1 | Vaira et al. [38] | Italy | Case series | 33 | 51.8 | Self-tested | 75.8% (n = 25) | Yes | Yes |
Notes: *Patients who have not been confirmed by laboratory tests; ▲ European countries: Including Belgium, France, Spain and Italy; ▲▲ Multiple countries: Including United States, Mexico, Italy, UK and Other.
★ Five odorants test: phenyl-ethyl-alcohol, cyclotene, isovaleric acid, undecalactone, and skatole; ★★ UPSIT: University of Pennsylvania Smell Identification Test; ★★★ le nez du vin: a quick test method of olfaction.