Introduction: It is clear that a proportion of patients continue to suffer long-lasting symptoms following acute infection with coronavirus disease 2019 (COVID-19). Persistent olfactory dysfunction is one of the commonest complaints reported in the condition colloquially known as long COVID (now known as post-acute sequelae of SARS-CoV-2 infection (PASC)). The prevalence, risk factors and clinical course of long COVID olfactory dysfunction are not yet well understood. At present, the main stay of treatment is olfactory training. Quantitative olfactory testing and impacts on patient quality of life have not been widely studied. This study describes our experiences at Wrightington, Wigan and Leigh Teaching Hospitals, UK (WWL) of establishing a COVID-19 smell clinic, along with preliminary data on patient demographics, baseline smell test scores and quality of life questionnaire scores before olfactory training.
Methods: We piloted a COVID-19 smell clinic. We recorded patient demographics and clinical characteristics then performed clinical assessment of each patient. Quantitative measurements of olfactory dysfunction were recorded using the University of Pennsylvania Smell Identification Test (UPSIT). We measured the impact of olfactory dysfunction on patient quality of life using the validated English Olfactory Disorders Questionnaire (eODQ).
Results: 20 patients participated in the clinic. 4 patients were excluded from analysis due to missing data. Median age was 35 years. 81% (n=13) of the participants were female. 50% (n=8) of patients suffered with a combination of anosmia/ageusia and parosmia, whilst 43% (n=7) of patients suffered with anosmia/ageusia without parosmia. Almost all the patients registered UPSIT scores in keeping with impaired olfaction. Patient scores ranged from 22 to 35, with the median score at 30. All patients reported that their olfactory dysfunction had an impact on their quality of life. The median eODQ score reported was 90, with scores ranging from 42 to 169 out of a maximum of 180.
Conclusion: We have demonstrated that it is simple and feasible to set up a COVID-19 smell clinic. The materials are inexpensive, but supervised completion of the UPSIT and eODQ is time-consuming. Patients demonstrate reduced olfaction on quantitative testing and experience significant impacts on their quality of life as a result. More research is needed to demonstrate if olfactory training results in measurable improvements in smell test scores and quality of life.