Patterns of smell recovery in 751 patients affected by the COVID‐19 outbreak

Abstract

Background and purpose: Post-viral olfactory dysfunction is well established and has been shown to be a key symptom of COVID-19 with more than 66% of European and US patients reporting some degree of loss of smell. Persistent olfactory dysfunction appears to be commonplace and will drive the demand for general practitioner, otolaryngology or neurology consultation in the next few monthsevidence regarding recovery will be essential in counselling our patients. Methods: This was a prospective survey-based data collection and telemedicine follow-up. Results: In total, 751 patients completed the study, of whom 477 were females and 274 males. The mean age of the patients was 41 AE 13 years (range 18-60). There were 621 patients (83%) who subjectively reported a total loss of smell and 130 (17%) a partial loss. After a mean follow-up of 47 AE 7 days (range 30-71) from the first consultation, 277 (37%) patients still reported a persistent subjective loss of smell, 107 (14%) reported partial recovery and 367 (49%) reported complete recovery. The mean duration of the olfactory dysfunction was 10 AE 6 days (range 3-31) in those patients who completely recovered and 12 AE 8 days (range 7-35) in those patients who partially recovered. Conclusions: According to our results, at this relatively early point in the pandemic, subjective patterns of recovery of olfactory dysfunction in COVID-19 patients are valuable for our patients, for hypothesis generation and for treatment development.

The coronavirus disease 2019: the prevalence, prognosis, and recovery from olfactory dysfunction (OD)

“…In a subgroup of patients who had OD at the time of presentation to referral centres, 58.8% were nearly or fully recovered. In a study by Chiesa-Estomba et al [17], 367 (49%) out of 751 patients were completely recovered from OD after a mean follow-up of 47 ± 7 days. Victor Gorzkowski et al [18] also reported in a study on 229 patients with COVID-19, 78.4% of patients were recovered within the fourth and the fifteenth day after olfactory loss onset with a complete olfactory recovery in 51.43% of patients.…”

The Association of “Loss of Smell” to COVID-19: A Systematic Review and Meta-Analysis

“…A total of 11074 COVID-19 patients (mean age 46.7±10.4 years and males 46.9%) were included in the final analysis ( table 1 ). 2 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 The overall prevalence of “loss of smell” in COVID-19 patients was 52.0% (CI: 42.5%-61.6%, I 2 =99.4%) ( Figure 2 ). A total of 21 studies compared these symptoms in COVID-19 patients (n=2196) and controls (n=3425).…”

Quantitative evaluation and progress of olfactory dysfunction in COVID-19

“…However, the persistence of olfactory dysfunction was reported for 277 patients (37%). The data obtained was subjective, since information on patients was acquired by questionnaires and follow-up was carried out via telemedicine [ 26 ]. In their study, Gelardi et al [ 27 ] reported that sensory symptoms lasted an average of 16.1 days (range 7–22 days), and of the patients, 37% completely recovered, 33% partially recovered, and 30% did not recover.…”