Published: August 30, 2021

Pearls from your Peers | Post-COVID Smell Loss

Cristina Cabrera-Muffly is joined by Anne Getz, MD, to discuss the aftereffects of smell loss in patients who have recovered from COVID-19.


Peers PeopleWhat is the incidence of post-COVID-19 smell loss among patients who have recovered from COVID? 

Loss of smell is very common in COVID-19. Up to 50% of patients report loss of smell, with approximately 10% experiencing long-term loss or smell distortion. 

Is there any truth to the idea that people with milder symptoms are more likely to have smell loss?

There does appear to be an inverse correlation between smell loss and severity of disease. One study showed that patients with loss of sense of smell actually had a fivefold decreased risk of death from COVID-19. It is hypothesized that a robust inflammatory reaction and cytokine response at the neuroimmune interface may be toxic to the olfactory system but may also indicate a strong immune response to the virus. 

Are you seeing more anosmia or parosmia type symptoms post-COVID infection?

Most patients in my practice are presenting with parosmia. When your coffee and chocolate smell like gasoline or garbage, it is incredibly disturbing. The negative impacts on quality of life and psychological well-being to some individuals should not be diminished. 

What is your diagnostic workup for post-COVID smell loss? 

The diagnostic workup primarily consists of a thorough history. I do not routinely obtain imaging if the patient has a clear history of smell loss associated with COVID-19 infection and absence of any other concerning symptoms or exam findings. I do routinely perform nasal endoscopy to visualize the olfactory cleft and assess the overall appearance and health of the mucosa. I offer the UPSIT if patients are interested in quantifying their degree of dysfunction and tracking change over time but do not routinely administer it. 

What treatment options do you typically recommend for post-COVID smell loss? 

Smell training has been shown to be helpful for many patients and is something I routinely recommend. Organizations such as AbScent and Fifth Sense have patient-friendly, online resources related to smell loss and smell training. Evidence supporting other therapies, such as topical and oral steroids, omega-3, intranasal theophylline, and vitamin A, for isolated smell loss is weak. These can be discussed as options for a patient on a case-by-case basis. 

If smell is going to recover, what is the typical time frame for this to happen?

Many patients will regain function within several weeks, but the regenerative process can be much slower, in some cases taking up to two years. The knowledge that parosmia can be a common experience is reassuring to patients. 

Do you counsel these patients on anything else specific regarding their smell loss?

Safety counseling is critical—making certain there are functioning smoke/carbon monoxide detectors in the home and urging attention to food expiration dates.

One of the most important things we can do is to validate the negative impact of decreased or altered sense of smell. Often times patients will state that they feel unjustified complaining about their sense of smell when they have otherwise emerged unscathed from COVID-19. I feel it is therapeutic to give license to the patient to be upset by their loss of normal function. Many post-COVID-19 smell loss support groups exist, and it can be helpful to urge a patient to seek these out.  

References:

1. Boscolo-Rizzo P, Borsetto D, Fabbris C, et al. Evolution of altered sense of smell or taste in patients with mildly symptomatic COVID-19. JAMA Otolaryngol Head Neck Surg. 2020;146(8):729-732. doi: 10.1001/jamaoto.2020.1379

2. Hopkins C, Alanin M, Philpott C, et al. Management of new onset loss of sense of smell during the COVID-19 pandemic—BRS consensus guidelines. Clin Otolaryngol. 2021;46(1):16-22. doi:10.1111/coa.13636

3. Lechien JR, Chiesa-Estomba CM, Hans S, Barillari MR, Jouffe L, Saussez S. Loss of smell and taste in 2013 European patients with mild to moderate COVID-19. Ann Intern Med. 2020;173(8):672-675. doi: 10.7326/M20-2428

4. Porta-Etessam J, Núñez-Gil IJ, González García N, et al. COVID-19 anosmia and gustatory symptoms as a prognosis factor: a subanalysis of the HOPE COVID-19 (Health Outcome Predictive Evaluation for COVID-19) registry. Infection. Published online March 1, 2021. doi: 10.1007/s15010-021-01587-9.


More from September 2021 – Vol. 40, No. 8